Argus: a new instrument for the measurement of the stratospheric dynamical tracers, N2O and CH4

We describe here a new instrument for the simultaneous, in situ measurement of the stratospheric tracer molecules, nitrous oxide (N2O) and methane (CH4). Argus is unique in its small size making it well suited for limited payload atmospheric research platforms. Argus employs second harmonic spectroscopy using tunable lead-salt diode lasers emitting in the mid-infrared. We first explain the Argus design philosophy followed by detailed descriptions of the instrument's optical, mechanical, and thermal sub-systems. Argus employs an in-flight calibration system providing real time calibrations and tightly constrained uncertainty estimates of the returned data. Data analysis is carried out using non-linear least-squares model fits to the acquired second harmonic spectra. A sampling of Argus data acquired on a recent stratospheric research campaign in the Arctic winter is presented.

The detection of large HNO3-containing particles in the winter Arctic stratosphere

Large particles containing nitric acid (HNO3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.

[Bilateral obstructive ecstasy of the kidneys in a newborn foal: a case study]

A report is given of obstructive ectasy of both kidneys in a newborn foal. Diagnosis and therapy are described as well as differential diagnosis.

Linker-insertion mutagenesis of Pseudomonas aeruginosa outer membrane protein OprF

The oprF gene, expressing Pseudomonas aeruginosa major outer membrane protein OprF, was subjected to semi-random linker mutagenesis by insertion of a 1.3 kb HincII kanamycin-resistance fragment from plasmid pUC4KAPA into multiple blunt-ended restriction sites in the oprF gene. The kanamycin-resistance gene was then removed by PstI digestion, which left a 12 nucleotide pair linker residue. Nine unique clones were identified that contained such linkers at different locations within the oprF gene and were permissive for the production of full-length OprF variants. In addition, one permissive site-directed insertion, one non-permissive insertion and one carboxyterminal insertion leading to proteolytic truncation were also identified. These mutants were characterized by DNA sequencing and reactivity of the OprF variants with a bank of 10 OprF-specific monoclonal antibodies. Permissive clones produced OprF variants that were shown to be reactive with the majority of these monoclonal antibodies, except where the insertion was suspected of interrupting the epitope for the specific monoclonal antibody. In addition, these variants were shown to be 2-mercaptoethanol modifiable, to be resistant to trypsin cleavage in intact cells and partly cleaved to a high-molecular-weight core fragment in outer membranes and , where studied, to be accessible to indirect immunofluorescence labelling in intact cells by monoclonal antibodies specific for surface epitopes. Based on these data, a revised structural model for OprF is proposed.

Out-patient hand surgery. A prospective study of 588 patients

The results of a prospective study of 588 patients operated on over a period of 4 months were analyzed. Of these patients, 6% only had to be hospitalized. The 555 other patients underwent out-patient surgery, 25% of which were emergencies. Thirty-four % of patients had one or more preexisting serious medical conditions. Ninety-one % underwent regional anesthesia. Complications were rare and did not seem to be preventable by hospitalization. While highlighting the many advantages associated with out-patient surgery, the authors stress the guidelines which must be followed as well as the pitfalls to be avoided in ambulatory surgery of the hand.

[The development of the adrenal cortex in pig (Sus scrofa domestica). (A contribution on the development of the fetal interior zone of the adrenal cortex in pig) (author's transl)]

The adrenals of pigs have been investigated histologically and histochemically during different periods of time pre- and postnatally. The pig (Sus scrofa domestica) shows a proper fetal cortex in the prenatal development of the adrenal gland. This involves slowly during the last quarter of pregnancy. A weight reduction is not noted thereby. Just before delivery the adrenal cortex of the pig has been subdivided into a zona arcuata and zona fasciculata. The zona reticularis develops only postnatally.

Phytohaemagglutinin-induced lymphocyte transformation and histologic findings in patients with chronic aggressive hepatitis before and during immunosuppressive therapy

In vitro lymphocyte transformation (14C-thymidine incorporation rate following stimulation by PHA) was studied in 19 patients with histologically proven chronic aggressive hepatitis. In the majority of the cases measurements were performed prior to and during a combined (azathioprine/corticosteroid) immunosuppressive therapy. In comparison to normal controls, the majority of the patients showed a significantly reduced lymphocyte transformation before the treatment started. During the immunosuppressive therapy there was a normalization of PHA-responsiveness in most of the patients, or an improvement, at least. Bioptic control seems to be the most reliable parameter to prove a therapeutic effect, since the histologic criteria for a decrease of the inflammatory activity were the last to occur. After transient cessation of the therapy, in 4 out of 6 cases a decrease of lymphocytic PHA-responsiveness was developed again, paralleled by histologic activation of the process where biopsy could be performed. This observation favours a long-term therapy for at least several years.

[Pseudo-LE syndrome after treatment with Venopyronum dragees] (author's transl)

During the past three years a pseudo-LE syndrome (with antimitochondrial antibodies) was diagnosed in 14 patients. Information from the patients and their doctors disclosed that twelve of them had taken Venopyronum dragees over a period of two months to five years before onset of first symptoms. Two of the patients died of nonspecific myocarditis. Clinical investigations strongly suggest that the drug may have played a role in the pathogenesis of the pseudo-LE syndrome which is likely to take a severe course if, as in the two patients, the cardiovascular system is involved.

[Monomeric igM in acute and chronic liver diseases (author's transl)]

Monomeric IgM could be found rather frequently in acute hepatitis and chronic aggressive hepatitis and occasionally also in chronic persistent hepatitis. Earlier it was reported in lympho-proliferative-, autoimmune diseases, some infectious diseases and in cirrhosis of the liver. The occurence of monomeric IgM in chronic aggressive hepatitis correlates with the detection of several autoantibodies (ANA, SMA, RF). The 7S-IgM-test may be used as an easily measurable additional criterium for diagnosis and course of chronic liver diseases.