Histochemische Untersuchungen an der Leber nach Verbrennung

Zusammenfassung An männlichen weißen Ratten wurde das Verhalten des Enzymmusters der Leber 72 Std nach Verbrühung untersucht. Es fanden sich Veränderungen im Sinne einer Aktivitätsverminderung bei der NAD-Cytochrom-c-Reduktase, Isocitronensäuredehydrogenase, ATPase und den PJS-positiven Substanzen. Eine Zunahme der Aktivität wurde bei der alkalischen Phosphatase und einigen Esterasen beobachtet, ebenso traten auch die scharlachrotfärbbaren Substanzen auf. Uneinheitliche Reaktionen zeigten die Succinodehydrogenase sowie die Leucinaminopeptidase, unverändert blieben Glukose-6-phosphat-dehydrogenase, -Glucuronidase, saure Phosphatase, die o-Diacetylbenzol- und die DDD-Reaktion.     

BIOSYNTHESIS OF COLLAGEN AND NON-COLLAGEN PROTEIN DURING DEVELOPMENT OF THE CHICK CORNEA

The relationship between the rates of increase of corneal protein fractions and incorporation of labeled precursors has been examined during embryonic and early posthatching development of the chick corneal stroma. Non-collagen protein increased gradually from 9 through 20 days of incubation. Collagen accumulated approximately logarithmically through the 19th day, the most rapid rate occurring between 13 and 20 days of incubation. The rates at which labeled amino acids are incorporated into collagen in vivo and in vitro undergo marked changes during the last week of embryonic development, corresponding closely to the rate of collagen accumulation in vivo; whereas incorporation into non-collagen protein changes much less markedly. Changes in the rate of incorporation of precursors into collagen are not due to changes in the rate of conversion of collagen from the soluble to insoluble form, or to changes in the endogenous amino acid pool size. Chick embryo corneal stroma collagen turns over very slowly, if at all. Non-collagen protein turns over more rapidly. An increase in cell number, as indicated by DNA content, does not account for the increased rate of collagen synthesis between the 9th and 16th day of incubation. It is concluded that the observed changes in collagen synthesis reflect changing activities in the individual cornea fibroblasts. These activities are comparable in the intact tissue in vivo and in isolated corneas in vitro.     

Experience with Electron Microscopy in the Differential Diagnosis of Smallpox

The usefulness of negative-contrast electron microscopy in the rapid differential diagnosis of poxvirus and herpesvirus exanthems is described in this study of 301 specimens from patients with vesicular exanthematous diseases. Specimens from patients with smallpox, various forms of vaccination complications, varicella, zoster (shingles), and herpes simplex are included in this evaluation. Electron microscopy, when applied to the study of lesion material, was found to be more sensitive than the classical techniques of virus isolation in the diagnosis of both poxvirus and herpes/varicella virus infections. However, since specific identification of a virus within a group cannot be made morphologically by electron microscopy, it is recommended that both electron microscopy and virus isolation methods be employed for the routine differential diagnosis of vesicular exanthematous diseases in the reference diagnostic laboratory.     

The invasive crayfish Faxonius immunis causes the collapse of macroinvertebrate communities in Central European ponds

Aquatic Ecology - The invasive crayfish Faxonius immunis is regarded as a threat to amphibians and macroinvertebrates in the Upper Rhine Valley, Germany, eradicating macrophytes and establishing...     

Atypical antipsychotic drugs and risk of ischaemic stroke: population based retrospective cohort study

Objective To compare the incidence of admissions to hospital for stroke among older adults with dementia receiving atypical or typical antipsychotics.Design Population based retrospective cohort study.Setting Ontario, Canada.Patients 32 710 older adults (≤ 65 years) with dementia (17 845 dispensed an atypical antipsychotic and 14 865 dispensed a typical antipsychotic).Main outcome measures Admission to hospital with the most responsible diagnosis (single most important condition responsible for the patient''s admission) of ischaemic stroke. Observation of patients until they were either admitted to hospital with ischaemic stroke, stopped taking antipsychotics, died, or the study ended.Results After adjustment for potential confounders, participants receiving atypical antipsychotics showed no significant increase in risk of ischaemic stroke compared with those receiving typical antipsychotics (adjusted hazard ratio 1.01, 95% confidence interval 0.81 to 1.26). This finding was consistent in a series of subgroup analyses, including ones of individual atypical antipsychotic drugs (risperidone, olanzapine, and quetiapine) and selected subpopulations of the main cohorts.Conclusion Older adults with dementia who take atypical antipsychotics have a similar risk of ischaemic stroke to those taking typical antipsychotics.     

K2P18.1 translates T cell receptor signals into thymic regulatory T cell development

It remains largely unclear how thymocytes translate relative differences in T cell receptor (TCR) signal strength into distinct developmental programs that driv...