BepiColombo mission confirms stagnation region of Venus and reveals its large extent

The second Venus flyby of the BepiColombo mission offer a unique opportunity to make a complete tour of one of the few gas-dynamics dominated interaction regions between the supersonic solar wind and a Solar System object. The spacecraft pass through the full Venusian magnetosheath following the plasma streamlines, and cross the subsolar stagnation region during very stable solar wind conditions as observed upstream by the neighboring Solar Orbiter mission. These rare multipoint synergistic observations and stable conditions experimentally confirm what was previously predicted for the barely-explored stagnation region close to solar minimum. Here, we show that this region has a large extend, up to an altitude of 1900 km, and the estimated low energy transfer near the subsolar point confirm that the atmosphere of Venus, despite being non-magnetized and less conductive due to lower ultraviolet flux at solar minimum, is capable of withstanding the solar wind under low dynamic pressure.

Inner southern magnetosphere observation of Mercury via SERENA ion sensors in BepiColombo mission

Mercury's southern inner magnetosphere is an unexplored region as it was not observed by earlier space missions. In October 2021, BepiColombo mission has passed through this region during its first Mercury flyby. Here, we describe the observations of SERENA ion sensors nearby and inside Mercury's magnetosphere. An intermittent high-energy signal, possibly due to an interplanetary magnetic flux rope, has been observed downstream Mercury, together with low energy solar wind. Low energy ions, possibly due to satellite outgassing, were detected outside the magnetosphere. The dayside magnetopause and bow-shock crossing were much closer to the planet than expected, signature of a highly eroded magnetosphere. Different ion populations have been observed inside the magnetosphere, like low latitude boundary layer at magnetopause inbound and partial ring current at dawn close to the planet. These observations are important for understanding the weak magnetosphere behavior so close to the Sun, revealing details never reached before.

SERENA: Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo

The ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase.

Abstract OT3-03-01: Open-label, single-arm study evaluating the antitumor activity and safety of niraparib as neoadjuvant treatment in patients with localized, HER2-negative, BRCA-mutant breast cancer

Background: Neoadjuvant chemotherapy is administered to patients with operable breast cancer to downstage the tumor to allow for less extensive surgery and to provide prognostic information about drug efficacy and risk of disease recurrence. Patients who achieve a pathological complete response (pCR) following neoadjuvant treatment have a more favorable outcome than patients with residual invasive disease. Single-agent poly(ADP-ribose) polymerase (PARP) inhibitors have clinical efficacy in BRCA-mutated breast cancer. Niraparib, a potent and selective PARP1/2 inhibitor, is approved for maintenance treatment of patients with recurrent ovarian cancer and has demonstrated strong antitumor activity in in vivo studies with BRCA1-mutant breast cancer. The objective of this study is to evaluate the antitumor activity of single-agent niraparib in the neoadjuvant treatment of patients with localized, human epidermal growth factor receptor 2 (HER2)-negative, BRCAmut breast cancer.

Trial Design: This is an open-label, single-arm pilot study with a target enrollment of 20 evaluable patients. Eligible patients are those ≥18 years old with histologically-confirmed HER2-negative localized breast cancer and either a BRCA1 or BRCA2 mutation (germline or somatic) and no prior anti-cancer therapies for the current malignancy. Patients will receive 200 mg of oral niraparib once daily for 2 months, after which they may either proceed directly to surgery or receive chemotherapy at the discretion of the physician. The primary endpoint is tumor response rate based on the change in tumor volume as measured by breast MRI after 2 months of treatment with niraparib; a response is defined as ≥30% reduction of tumor volume from baseline. Secondary endpoints include pCR rate, tumor response rate based on the change in tumor volume as measured by breast ultrasound, and safety and tolerability. Data will be summarized in a descriptive nature by frequency distributions (number and percentage of patients) for categorical variables and by the mean, median, and standard deviation for continuous variables. Tumor response rate will be tabulated together with its 95% binomial exact confidence interval.

Funding: TESARO, Inc., Waltham, MA, USA sponsored the study.

Citation Format: Han H, Hamilton E, Irie H, Isakoff S, Jelovac D, Liem A, Liu MC, Milillo A, Nangia J, Page D, Reeves J, Santa-Maria C, Duncan M, Graham JR, Chen J, Dezube BJ, Spring L. Open-label, single-arm study evaluating the antitumor activity and safety of niraparib as neoadjuvant treatment in patients with localized, HER2-negative, BRCA-mutant breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-03-01.

Abstract P2-02-16: Use of cell-free circulating RNA and expression of PD-L1 and HER2 in plasma to monitor and predict clinical response in metastatic breast cancer patients

Background: In addition to traditional radiology tests, cell-free circulating tumor RNA (cfRNA) extracted from plasma of cancer patients (pts) provides a means of evaluating tumor response, but based on molecular changes in the tumor. Measuring dynamic changes in gene expression and levels of total cfRNA (per ml of plasma) in metastatic patients has shown great potential for evaluating disease status and predicting outcome to anti-tumoral therapy in advance of imaging. Though checkpoint inhibitors have not been assessed widely in breast cancer, TNBC has shown mild responses to pembrozilumab and atezolizumab, with significantly better responses in pts with detectable PD-L1 expression.

Methods: Blood was drawn from pts at approximately 6-week intervals under various therapies and CT scans were performed at approximately 3-month intervals. CfRNA was extracted from the resulting plasma and reverse transcribed with random hexamers to cDNA. Levels of cfRNA were quantitated by RT-qPCR and correlated with pt response (PR/SD/PD), as determined by CT scans. Levels of gene expression in cfRNA (including PD-L1 and HER2) were monitored in pts across blood draws.

Results: A total of 28 breast cancer pts were enrolled in a 1-year clinical study. Of pts, 39% (11/28) were Caucasian and 36% (10/28) Hispanic. 19 pts completed the first two cycles of therapy: 2 pts had PR and showed no change (NC) or decrease (DEC) in levels of cfRNA, 11 pts achieved SD with 8 showing DEC or NC in cfRNA levels, and 6 pts had PD and all underwent increases (INC) in cfRNA levels (median increase: 788 ng/mL plasma) which correlated with progressive disease status. Of pts with SD/PR, 4 showed either an emergence or significant increase in PD-L1 expression across blood draws (3.7-98 ct); of PD pts, 1 showed a significant emergence of PD-L1 expression (12.5 ct) across blood draws. 3/5 of these PD-L1 expressing pts were being treated with an everolimus combination; the emergence or increase of PD-L1 in response to this therapy suggests use of checkpoint inhibitors as an option for these pts. In response to therapy, 3 of 5 pts had PD-L1 cfRNA levels above levels predictive of response to nivolumab in lung cancer pts. In the only pt with hyperexpressed HER2, the disappearance of HER2 cfRNA matched positive response (PR) to treatment with trastuzumab. PD-L1 decreased concomitantly for this pt.

Conclusion: We found a strong correlation between clinical responses and changes in plasma levels of ctRNA in breast cancer (84%). Most of these were documented several weeks before imaging was done. Levels of PD-L1 and HER2 expression in plasma can also be used to monitor pt response to specific therapies. The emergence of PD-L1 expression in response to various therapies in breast cancer may confer sensitivity to checkpoint inhibitor therapy.

Citation Format: Castrellon AB, Velez M, Raez LE, Danenberg K, Rabizadeh S, Usher J, Jaimes Y, Hunis B, Bittencourt AC, Milillo A, Blaya M, Habaue C, Danenberg PV. Use of cell-free circulating RNA and expression of PD-L1 and HER2 in plasma to monitor and predict clinical response in metastatic breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-16.

A rare case of blunt thoracoabdominal trauma with small bowel perforation from air bags

Vehicle collisions represent more than 75% of mechanism of blunt abdominal trauma. In spite of the incomparable improvement of car safety devices, recent studies pointed out that the air bags might cause injuries, specially when it is not associated with seatbelt. In fact, some studies pointed out that crash victims using air bags alone have increased injury severity, hospitalisations, thoracoabdominal procedure, and rehabilitation. Some of the most frequently injured organs reported from air bag deployment are the liver (38%), the spleen (23%) and digestive system (17%). Injury of the hollow viscera are far less common. In particular, blunt abdominal trauma resulting in small bowel perforation is an infrequent lesion. These injuries are difficult to diagnose because specific signs are poor and a delay in treatment increases mortality and morbidity of the patients. We describe a case of thoracoabdominal trauma that occurred during a head-on collision after an air bag deployment without seatbelt use.

[Non palpable testis in adult: laparoscopic treatment]

Cryptorchidism has an incidence of 0.8 - 2%, being undescendent testis nonpalpable in 20% of the cases. The latters have an increased risk of malignant transformation, infertility and epididymal malformation. Surgical treatment of nonpalpable testis is prone to failure compared to the palpable ones. Many diagnostic methods have been described; the most promising is the use of diagnostic laparoscopy which, compared to the imaging modalities, is more reliable to determine the site of the nonpalpable testis.

[Surgical education: from teledidactics to virtual training]

The assessment of efficacy and quality of computer-assisted learning is today under evaluation. The Authors propose to use distant learning in the surgical knowledge teaching. In Italy, thanks to the Ministry of University and Scientific Research, a Master on distant learning in Medicine is now starting in 11 Italian Universities under the coordination of the second Faculty of Medicine of the University of Rome 'La Sapienza'. Thanks to the help of medicine and surgery teachers and informatics and telecommunication engineers, this Master is a first step to form and to license medical and surgical specialists experts in distant learning and videoconferencing telemedicine. Videoconferencing system can support Telementoring. Telementoring isn't an exclusive methodology but it is an additional methodology to tradictional didactic for clinicians and surgeons. It allows personal virtual trainings using computers and telecommunication systems.

[Rhomboid flap in radical surgical treatment of sacrococcygeal fistulas: technical notes]

The Authors report their experience in surgical management of sacrococcygeal fistulas treated by radical excision and subcutaneous/cutaneous rhomboid flap. This is a simple, safe surgical technique and the patients can be treated in day surgery by spinal anesthesia.

Solar Wind-Induced Atmospheric Erosion at Mars: First Results from ASPERA-3 on Mars Express

The Analyzer of Space Plasma and Energetic Atoms (ASPERA) on board the Mars Express spacecraft found that solar wind plasma and accelerated ionospheric ions may be observed all the way down to the Mars Express pericenter of 270 kilometers above the dayside planetary surface. This is very deep in the ionosphere, implying direct exposure of the martian topside atmosphere to solar wind plasma forcing. The low-altitude penetration of solar wind plasma and the energization of ionospheric plasma may be due to solar wind irregularities or perturbations, to magnetic anomalies at Mars, or both.