The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission.

NASA's Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.

Influence of thyroglobulin on basal and stimulated human thyroid adenylate cyclase activity.

The interaction of thyroglobulin (Tg), thyroid-stimulating immunoglobulins (TSI), and TSH on human thyroid plasma membranes from nontoxic goiter was studied in vitro by an adenylate cyclase assay system using human thyroid homogenate. Purified Tg [3 X 10(-10) M (0.2 micrograms/ml) to 3 X 10(-8) M (20 micrograms/ml)] exerted a dose- and time-dependent inhibitory influence on basal adenylate cyclase activity. The inhibition was prevented by preincubation with Tg antibody in excess. Tg (3 X 10(-8) M) caused a significant reduction in the TSH- and TSI-stimulated adenylate cyclase activities, but did not influence stimulation with NaF (8 mM). Fractions of thyroid homogenates were obtained by differential centrifugation, and the maximal inhibitory influence of Tg was located in the 5000 X g fraction. Thus, Tg is an efficient inhibitor of basal and TSH- or TSI- stimulated adenylate cyclase activities, and might be involved in a short loop counterregulation of thyroid adenylate cyclase sensitivity in vivo.

[Ventricular tonometry during laparoscopic cholecystectomy]. / Ventrikeltonometri under laparoskopisk kolecystektomi.

Changes in gastric mucosal-pH (pHi) are correlated with the oxygenation of the gastric mucosa. We have measured the gastric mucosal-pH (pHi) in 11 healthy patients undergoing laparoscopic cholecystectomy and calculated the "pH-gap" as the difference between arterial-pH and pHi. The measurements were obtained at 30 minute intervals from the induction of anaesthesia to the end of surgery. The pHi decreased during surgery, but the pH-gap showed only insignificant changes. The results of this study did therefore not indicate gastric mucosal hypoxia during laparoscopic cholecystectomy.

[Incisional hernia. A study of morbidity, mortality and bed utilization in a Danish county]. / Hernia incisionalis. En opgørelse af morbiditet, mortalitet og sengedagsforbrug i et dansk amt.

Four hundred and four patients operated for ventral hernia during a five year period were reviewed with special emphasis on morbidity, mortality and number of days in hospital. The patients were divided into 357 patients who had been operated for ventral hernia only once (A) and 47 patients who had been operated more than once for ventral hernia (B). There were no significant differences between the two groups regarding to ages or preoperative condition. The postoperative complications were 21% in group A and 12% in group B, although this was not statistically significant. Of those who suffered a complication after the operation, 76% had a competing illness prior to the operation. The overall mortality was 0.5%. The patients were hospitalized for a total of 4846 days. In view of the results of this material and of the high recurrence rate demonstrated in the literature, a restrictive attitude towards operations for ventral hernia is recommended.

Thyroid function and plasma cyclic AMP response to intravenous glucagon.

The glucagon stimulated increase in plasma cyclic AMP has been studied in 17 healthy subjects, in 13 hyperthyroid and in 14 hypothyroid patients. Six hyperthyroid and 2 hypothyroid patients were re-investigated after at least 15 months of treatment. The results show: 1) The glucagon stimulated cyclic AMP response is significantly increased in hyperthyroid patients considered as a group, and is reduced in patients with hypothyroidism. 2) Three hyperthyroid and 4 hypothyroid patients showed a normal response to iv glucagon, indicating that the plasma cyclic AMP response to iv glucagon is not a sensitive test for the evaluation of peripheral thyroid states. This suggests that the effects of thyroid hormones in the liver does not necessarily follow the effects in other tissues. 3) Re-investigation of treated patients showed that the cyclic AMP response can be normalized by treatment, both in hyperthyroidism and hypothyroidism. However, in patients treated for hyperthyroidism a hyper-response to glucagon can continue after blood levels of thyroid hormones are reduced to normal. This suggests an inertia in the loss of the hyper-response to glucagon, once a hyperfunction has been induced. A similar inertia in the loss of glucagon sensitivity in hypothyroidism could explain the large number of normal tests in hypothyroid patients.

TSH and thyroid stimulating antibodies (TSAb) activate thyroid adenylate cyclase through different pathways.

Adenylate cyclase activity in human thyroid homogenates was studied after stimulation with thyrotropin (TSH) and thyroid stimulating antibodies (TSAb). The results show: 1) TSAb prepared from different patients with Graves' disease show different adenylate cyclase activation patterns and a lag phase is frequently observed. 2) TSH and TSAb appear to cause mutually inhibitory activation of thyroid adenylate cyclase. 3] The maximal adenylate cyclase activation is higher with TSH than with TSAb, but this could possibly be due to contamination of TSAb preparations with an adenylate cyclase inhibitor. 4) There is no absolute copurification of TSH sensitive and TSAb sensitive adenylate cyclase in various subcellular fractions of thyroid homogenate. 5) Incubation of thyroid homogenate with cortisol cause a dose dependent decrease in the adenylate cyclase response to TSAb whereas the response to TSH is either increased or unchanged. The results indicate that TSH and TSAb activate thyroid adenylate cyclase through different pathways in the plasma membrane.

A simple competitive protein-binding assay for adenosine-3',5'-monophosphate in plasma and urine.

A modified competitive protein-binding assay for the measurement of adenosine-3',5'-monophosphate is described. The procedure allows measurement of adenosine-3',5'-monophosphate in unextracted plasma samples. The mean plasma values in 25 normal, fasting and ambulatory subjects were 22.7 +/- 4.7 pmol/ml (mean +/- SD) (range 13-31 pmol/ml. The mean urinary content was 3.2 +/- 1.0 mumol per g creatinine (mean +/- SD) (n=24).

Cyclic AMP, glucose and cortisol in plasma during surgery.

Cyclic AMP, glucose and cortisol in plasma were measured before, during and after major surgery (hysterectomy, six patients) and minor surgery (tympanoplasty, 10 patients). During major surgery cyclic AMP as well as glucose and cortisol showed a pronounced increase. During minor surgery cyclic AMP, glucose and cortisol levels were significantly lower than in the group undergoing major surgery. It is concluded that the increase of plasma cyclic AMP during operative procedures is related to the severity of the trauma.

Effect of human leucocyte migration inhibitory factor (LIF) on 3', 5'-cyclic AMP levels of peripheral blood leucocytes.

The possible involvement of 3', 5'-cyclic AMP (cyclic AMP) in the mechanism of action of leucocyte migration inhbitory factory (LIF) was tested. LIF-treated human peripheral blood leucocytes were incubated at 37 degrees C for various times between 0 and 22 h. The concentrations of cyclic AMP in these cultures did not differ from those in controls. Furthermore, LIF did not affect the cellular release of cyclic AMP. Neither when testing purified neutrophils, which are the prime targets of LIF action, an effect of LIF was found. Cyclic AMP levels decreased with time of incubation, whether testing mononuclear cells (92 per cent lymphocytes), purified neutrophils (98 per cent), or buffy coat cells (72 per cent neutrophils; 22 per cent lymphocytes). However, a transient and as yet unexplained increase in the cyclic AMP levels of the latter mixed population of cells was manifested within 10 to 30 min of incubation.

Effect of furosemide on parathyroid hormone stimulated guinea pig renal adenylate cyclase and thyrotrophin and fluoride stimulated human thyroid adenylate cyclase.

The effect of furosemide 8 X 10(-4) mol/l an 8 X 10(-5) mol/l on parathyroid hormone stimulated adenylate cyclase was studied in renal tissue slices from guinea pigs. Furosemide caused a dose-dependent inhibition of the effect of parathyroid hormone on production of cyclic AMP, without having any significant effect on the basal cyclic AMP production. Furosemide in similar concentrations did not inhibit the stimulatory effect of thyrotrophin and fluoride in human thyroid homogenates suggesting that furosemide is not an universal inhibitor of adenylate cyclase and that the inhibition is not caused by a direct action of furosemide on the adenylate cyclase enzyme. Furosemide did not interfere with binding of cyclic AMP to cyclic AMP binding protein kinase from rabbit muscle. The results indicate that furosemide exerts an inhibitory influence either upon binding of parathyroid hormone to renal receptors or upon transmission of impulse from receptor to adenylate cyclase. The inhibitory influence of furosemide on parathyroid hormone action in kidney could explain the value of furosemide in the acute treatment of hypercalcaemia, but also suggest that chronic treatment with furosemide might interfere with normal calcium metabolism.

In vitro lymphocyte proliferation in response to polyclonal activators and microbial antigens, and production of immunoglobulins stimulating thyroid adenylate cyclase in Graves' disease.

Cultures of blood lymphocytes from 16 patients with Graves' disease (GD) and 14 matched controls were studied. Incorporation of [14C]thymidine was significantly increased in unstimulated cultures of GD lymphocytes, while the incorporation after stimulation with polyclonal activators (concanavalin A, pokeweed mitogen, phytohaemagglutinin), microbial antigens (E. coli, Candida albicans extract, purified protein derivative of tuberculin, Yersinia enterocolitica serotype 3) and subcellular fractions of human thyroid antigens did not differ from the controls. Due to the increased incorporation in unstimulated cultures, stimulation index is not suitable as an indicator of lymphocyte sensitization. After polyclonal activation or stimulation with thyroid antigens the lymphocytes were cultured for up to 21 days, and the supernatants were investigated for thyroid adenylate cyclase stimulating immunoglobulins (TACSI). No TACSI were demonstrated in supernatants of the lymphocyte cultures neither afer polyclonal activation nor after specific stimulation with several thyroid antigens.