Mutations in SOX2 cause anophthalmia-esophageal-genital (AEG) syndrome

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Methylmercury poisoning: Long-term clinical,radiological, toxicological,and pathological studies of an affected family

For 3 months in 1969 a family in the United States that included a pregnant mother consumed pork containing methylmercury. Children, aged 20, 13, and 8 years and a neonate, developed severe neurological signs. Twenty-two years later, the 2 oldest had cortical blindness or constricted visual fields, diminished hand proprioception, choreoathetosis, and atentional deficits. Magnetic resonance images showed tissue loss in the calcarine and parietal cortices and cerebellar folia. The youngest had quadriplegia, blindness, and severe mental retradation until their deaths. The brain of the 8-year-old who died at age 30 showed cortical atrophy, neuronal loss, and gliosis, most pronounced in the paracentral and parietooccipital regions. The total mercury level in formalin-fixed, left occipital cortex was 1,974 ng/gm as measured by atomic absorption. Regional brain mercury levels correlated with extent of brain damage. A control patient had 38.5 ng of mercury/gm in the occipital cortex. Systemic organs in the patient and a control subject had comparable mercury levels. In mercury-intoxicated rats, we found that only 5 to 10% of total brain mercury was lost by formalin fixation. Brain inorganic mercury in the patient ranged from 82 to 100%. Since inorganic mercury crosses the blood-brain barrier poorly, biotransformation of methyl to inorganic mercury may have occurred after methylmercury crossed the blood-brain barrier, accounting for its persistence in brain and causing part of the brain damage.     

Mortality of a municipal-worker cohort: IV. Fire fighters

Morbidity and mortality studies of fire fighters have produced varied and inconsistent findings regarding the potential chronic effects of fire fighting including respiratory disease, cardiovascular disease, and cancer. The mortality experience of 1,867 white male fire fighters who were employed for the City of Buffalo a minimum of five years with at least one year as a fire fighter was studied. Vital status was determined for 99% of the cohort, resulting in 470 observed deaths. The fire fighter cohort was characteristic of a healthy worker population. All-cause mortality was close to the expected standardized mortality ratio (SMR) = 95, and significantly lower than expected mortality was seen for all external causes (SMR = 67)--in particular, for suicide (SMR = 21) and respiratory diseases (SMR = 48). Significantly elevated SMRs were found for benign neoplasms (SMR = 417), cancer of the colon (SMR = 183), and cancer of the bladder (SMR = 286). Cause-specific mortality is presented by number of years employed, calendar year of death, year of hire, and latency. Cancer mortality was significantly higher in the long-term fire fighters, and risk of mortality from all malignant neoplasms tended to increase with increasing latency. Patterns in risk of mortality among fire fighters for cancers of the bladder, colon, and brain are intriguing. Additional follow-up of this cohort and initiation of cancer morbidity studies would be helpful in further clarifying the potential long-term effects of fire fighting on cancer risk.     

Metabolic products of microorganisms. 255. Nikkomycins Wz and Wx, new chitin synthetase inhibitors from Streptomyces tendae

Two new dipeptidyl nikkomycins of the Z and X type were isolated from the culture broth of Streptomyces tendae TU 901/395-11/32 and characterized. They show a variation in the amino acid moiety of the molecule. Nikkomycin Wz is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to uracil, whereas nikkomycin Wx is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to 4-formyl-4-imidazolin-2-one. The new nikkomycins are good inhibitors of chitin synthetase from Coprinus cinereus but they did not inhibit growth of fungi and yeasts.     

A rapid method for electron beam energy check.

Assessment of electron beam energy and its long term stability is part of standard quality assurance practice in radiation oncology. Conventional depth-ionization or depth-film density measurements are time consuming both in terms of data acquisition and analysis. A procedure is described utilizing ionization measurements at two energy specific depths. It is based on a linear relationship between electron beam energy and its practical range. Energy shifts within the range covered by the two measurement depths are easily resolved. Within a range of +/- 0.50 MeV (+/- 1.30 MeV) around the established mean incident energy of 5.48 MeV (20.39 MeV), the method accuracy is better than 0.10 MeV.