A combined approach of conventional and molecular cytogenetics for detailed karyotypic analysis of the small cell lung carcinoma cell line U2020

Until recently the ability to analyze complex karyotypic rearrangements was totally dependent upon light microscopy of G-banded chromosomes. Developments in the area of molecular cytogenetics have revolutionized such analysis, making it possible to determine the nature of complex rearrangements. An extensive analysis has been made of the small cell lung carcinoma (SCLC) cell line U2020, using a combined approach of conventional and molecular cytogenetics, enabling a highly detailed karyotype to be constructed revealing rearrangements previously undetected by G-banding alone. This approach offers the opportunity to reassess other tumor karyotypes, particularly those of high complexity found in solid tumors, for tumor-specific consistent rearrangements indecipherable by conventional karyotyping.     

Expect the worse or hope for the best? Prenatal diagnosis of geleophysic dysplasia

Geleophysic dysplasia is a rare, autosomal recessive disorder which causes disproportionate short stature associated with severe physical handicaps, but is compatible with survival into adulthood. We present a case, a first-born child, where genetic counselling difficulties arose following ultrasound recognition of short-limbed dwarfism in association with polyhydramnios and an initial incorrect prenatal diagnosis of lethal chondrodysplasia. After birth of the surviving affected infant, the parents had great difficulty accepting that there had been a prenatal misdiagnosis and they were greatly disappointed by our inability to predict the postnatal survival of an infant to whom no hope of life had previously been given. The correct diagnosis was not made until the proband was nearly 1 year old, and the true prognosis then became clearer. This experience underlines the relative ease of prenatal recognition of skeletal growth abnormalities compared with the considerable difficulties experienced in reaching a precise diagnosis. Thus, following prenatal diagnosis of unspecified chondrodysplasia when parents seek definite information about the prognosis, the temptation to be either overpessimistic or overoptimistic should be avoided.     

Channeling of three newly introduced antidepressants to patients not responding satisfactorily to previous treatment

OBJECTIVE: Trifluoromethane and CO are produced simultaneously during the breakdown of isoflurane and desflurane by dry CO2 absorbents. Trifluoromethane interferes with anesthetic agent monitoring, and the interference can be used as a marker to indicate anesthetic breakdown with CO production. This study tests representative types of gas monitors to determine their ability to provide a clinically useful warning of CO production in circle breathing systems. METHODS: Isoflurane and desflurane were reacted with dry Baralyme at 45 degrees C. Standardized samples of breakdown products were created from mixtures of reacted and unreacted gases to simulate the partial degrees of reaction which might result during clinical episodes of anesthetic breakdown using 1% or 2% isoflurane and 6% or 12% desflurane. These mixtures were measured by the monitors tested, and the indication of the wrong agent or a mixture of agents due to the presence of trifluoromethane was recorded and related to the CO concentration in the gas mixtures. RESULTS: When presented with trifluoromethane from anesthetic breakdown, monochromatic infrared monitors displayed inappropriately large amounts of isoflurane or desflurane. Agent identifying infrared and Raman scattering monitors varied in their sensitivity to trifluoromethane. Mass spectrometers measuring enflurane at mass to charge = 69 were most sensitive to trifluoromethane. CONCLUSION: Monochromatic infrared monitors were unable to indicate anesthetic breakdown via interference by trifluoromethane, but did indicate falsely elevated anesthetic concentrations. Agent identifying infrared and Raman monitors provided warning of desflurane breakdown via the interference of trifluoromethane by displaying the wrong agent or mixed agents, but may not be sensitive enough to warn of isoflurane breakdown Some mass spectrometers provided the most sensitive warnings to anesthetic breakdown via trifluoromethane, but additional data processing by some patients monitor units reduced their overall effectiveness.