Outline of a Theory of non-Rankine-Hugoniot Shock Wave in Weak Mach Reflection

At the previous AFMC, the background for expecting a departure from Rankine-Hugoniot theory at the base of the reflected shock wave in weak Mach reflection was exposed. The results of some pertinent experiments performed in the supersonic wind tunnel were then presented. They confirmed the hypothesised irregular behaviour. In the present contribution, the elaboration of a theory of transgressed shock wave properties is presented. This concept enables to calculate the modified jump process. It fully accounts for the known experimental observations. It is the unyielding boundary conditions that prevail beyond regular reflection which force this remarkable deviation from the classical shock wave theory to take place

Mosaics of canopy openness induced by tropical cyclones in lowland rain forests with contrasting management histories in northeastern Australia

Tropical Cyclone 'Rona' crossed the coast of the Daintree lowlands of northeastern Australia in 1999. This study reports on its impact on forest canopy openness at six lowland rain forest sites with contrasting management histories (old-growth, selectively logged and regrowth). Percentage canopy openness was calculated from individual hemispherical photographs taken from marked points below the forest canopy at nine plots per site 3±4 mo before the cyclone, and at the same points a month afterwards. Before the cyclone, when nine sites were visited, canopy openness in old-growth and logged sites was similar, but significantly higher in regrowth forest. After the cyclone, all six revisited sites showed an increase in canopy openness, but the increase was very patchy amongst plots and sites and varied from insignificant to severe. The most severely impacted site was an old-growth one, the least impacted a logged one. Although proneness to impact was apparently related to forest management history (old-growth being the most impacted), underlying local topography may have had an equally strong influence in this case. It was concluded that the likelihood of severe impact may be determined at the landscape-scale by the interaction of anthropogenic with meteorological, physiographic and biotic factors. In the long term, such interactions may caution against pursuing forest management in cyclone-prone areas

Human μ-calpain: Simple isolation from erythrocytes and characterization of autolysis fragments

Heterodimeric μ-calpain, consisting of the large (80 kDa) and the small (30 kDa) subunit, was isolated and purified from human erythrocytes by a highly reproducible four-step purification procedure. Obtained material is more than 95% pure and has a specific activity of 6 - 7 mU/mg. Presence of contaminating proteins could not be detected by HPLC and sequence analysis. During storage at -80 °C the enzyme remains fully activatable by Ca²⁺, although the small subunit is partially processed to a 22 kDa fragment. This novel autolysis product of the small subunit starts with the sequence (60)RILG and is further processed to the known 18 kDa fragment. Active forms and typical transient and stable autolysis products of the large subunit were identified by protein sequencing. In casein-zymograms only the activatable forms 80 kDa+30 kDa, 80 kDa+22 kDa and 80 kDa+18 kDa displayed caseinolysis

Endometriosis and Isthmocele: Common or Rare?

Higher cesarean section rates and better ultrasound diagnostics have led to a more frequent diagnosis of isthmocele, a cesarean scar defect. Sometimes, endometriosis is found in the isthmocele, but simultaneous extrauterine endometriosis and endometriosis in the isthmocele have not yet been reported. Additionally, the surgical technique to repair the isthmocele is the subject of ongoing controversy. The aim of this study is to analyze a possible correlation between uterine scar (isthmocele) endometriosis and extrauterine endometriosis and to investigate the outcome of laparoscopic isthmocele resection in the rendezvous technique. In this single-center retrospective study, we included 83 women of reproductive age with symptomatic isthmocele undergoing laparoscopic isthmocele repair in rendezvous technique from 2004 to 2020 at the University of Bern. We collected data on patient and surgical characteristics as well as on postoperative outcomes (symptoms, further pregnancy, and pregnancy outcomes) retrospectively. We analyzed and compared these data for patients with and without endometriosis. Endometriosis was diagnosed during surgery in 22 out of 83 operated patients (26.5%). Diagnosis of isthmocele endometriosis (n = 9, 11%) was significantly higher in patients with extrauterine endometriosis (n = 6, p = 0.004). While the duration of surgery was significantly longer for patients with endometriosis (p = 0.006), the groups did not differ with regard to blood loss or complications. In addition, both groups showed similar indications for isthmocele repair (infertility, abnormal uterine bleeding, or dysmenorrhea). Surgery significantly improved abnormal uterine bleeding (χ2 p < 0.001), dysmenorrhea (χ2, p = 0.03), and infertility (χ2, p < 0.001). Regardless of the presence of endometriosis, 25 of 40 (63%) infertile patients became pregnant after surgery. In one out of eight pregnancies, however, we observed scar complications during pregnancy such as uterine scar pregnancy (n = 3), uterine scar dehiscence (n = 3), and placenta previa (n = 1). Endometriosis is a non-negligible intraoperative finding in patients with symptomatic isthmocele. The laparoscopic approach in the rendezvous technique is safe and effective. Therefore, this method should be recommended, especially in women with secondary infertility, and preoperatively simultaneous endometriosis resection should be discussed with the patient. In follow-up, postoperative pregnancies have to be monitored with care

Pathological processing of sentinel lymph nodes in endometrial carcinoma - routine aspects of grossing, ultra-staging, and surgico-pathological parameters in a series of 833 lymph nodes.

Sentinel lymph nodes are widely accepted in the treatment of endometrial carcinoma. Whereas surgical aspects are well studied, the pathological work-up in terms of grossing, frozen section, and the so-called ultra-staging is still a matter of debate. This results in conflicting national or center-based recommendations. In a series of consecutive 833 sentinel lymph nodes from 206 patients in endometrial carcinomas, we compared three different grossing techniques and the use of frozen section in terms of anatomy, detection rates, and survival. In total, 42 macro-metastases, 6 micro-metastases, and 25 nodes with isolated tumor cells were found. Lymph nodes affected at least with micro-metastasis were about 0.5cm enlarged. Detection rates in lamellation technique increased with a step of 5.9% to 8.3% in comparison to bi-valved or complete embedding. The lamellation technique presented with a slight beneficial prognosis in pN0 subgroup (OS, p=0.05), which besides size effects might be attributed to trimming loss. In frozen section, this effect was less pronounced than expected (OS, p=0.56). Ultra-staging only revealed additional micro-metastases and isolated tumor cells. Exclusively, macro-metastases showed poor survival (p<0.001). In multivariate analysis, T-stage, subtype, and lympho-vascular invasion status outperformed this staging parameter significantly. Grossing of sentinel lymph nodes is the most essential step with evidence to prefer lamellation in 2 mm steps. Step sectioning should consider widely spaced protocols to exclude macro-metastases. Frozen sections might add value to the intra-operative assessment of endometrial carcinoma in selected cases. The excellent biological behavior of cases with isolated tumor cells might question the routine application of pan-cytokeratin as ultra-staging method

Time to first recurrence, pattern of recurrence, and survival after recurrence in endometrial cancer according to the molecular classification.

OBJECTIVE Despite its generally favorable prognosis at primary diagnosis, recurrence of endometrial cancer remains an important clinical challenge. The aim of this study was to analyze the value of molecular classification in recurrent endometrial cancer. METHODS This study included patients with recurrent endometrial cancer who underwent primary surgical treatment between 2004 and 2015 at the Karolinska University Hospital, Sweden and the Bern University Hospital, Switzerland (KImBer cohort) with molecular classification of the primary tumor. RESULTS Out of 594 molecularly classified endometrial cancer patients, 101 patients experienced recurrence, consisting of 2 POLEmut, 33 MMRd, 30 p53abn, and 36 NSMP tumors. Mean age at recurrence was 71 years and mean follow-up was 54 months. Overall, median time to first recurrence was 16 months (95% CI 12-20); with the shortest median time in MMRd patients, with 13 months (95% CI 5-21). The pattern of recurrence was distinct among molecular subgroups: MMRd tumors experienced more locoregional, while p53abn cases showed more abdominal recurrences (P = .042). Median survival after recurrence was best for MMRd cases (43 months, 95% CI 11-76), compared to 39 months (95% CI 21-57) and 10 months (95% CI 7-13) for the NSMP and p53abn cases respectively (log-rank, P = .001). CONCLUSION Molecular classification is a significant indicator of survival after recurrence in endometrial cancer patients, and patterns of recurrence differ by molecular subgroups. While MMRd endometrial cancer show more locoregional recurrence and the best survival rates after recurrence, p53abn patients experience abdominal recurrence more often and had the worst prognosis of all recurrent patients

Enantiospecific pharmacokinetics of intravenous dexmedetomidine in beagles

The goal of this study was to investigate the pharmacokinetic (PK) behaviour of dexmedetomidine in dogs administered as a pure enantiomer versus as part of a racemic mixture. Eight unmedicated intact purpose-bread beagles were included. Two intravenous treatments of either medetomidine or dexmedetomidine were administered at 10- to 14-day intervals. Atipamezole or saline solution was administered intramuscularly 45&nbsp;min later. Venous blood samples were collected into EDTA collection tubes, and the quantification of dexmedetomidine and levomedetomidine was performed by chiral LC–MS/MS. All dogs appeared sedated after each treatment without complication. Plasma concentrations of levomedetomidine were measured only in the racemic group and were 51.4% (51.4%–56.1%) lower than dexmedetomidine. Non-compartmental analysis (NCA) was performed for both drugs, while dexmedetomidine data were further described using a population pharmacokinetic approach. A standard two-compartment mammillary model with linear elimination with combined additive and multiplicative error model for residual unexplained variability was established for dexmedetomidine. An exponential model was finally retained to describe inter-individual variability on parameters of clearance (Cl1) and central and peripheral volumes of distribution (V1, V2). No effect of occurrence, levomedetomidine or atipamezole could be observed on dexmedetomidine PK parameters. Dexmedetomidine did not undergo significantly different PK when administered alone or as part of the racemic mixture in otherwise unmedicated dogs