Periodic Bedrock Ridges at the ExoMars 2022 Landing Site: Evidence for a Changing Wind Regime.

Wind-formed features are abundant in Oxia Planum (Mars), the landing site of the 2022 ExoMars mission, which shows geological evidence for a past wet environment. Studies of aeolian bedforms at the landing site were focused on assessing the risk for rover trafficability, however their potential in recording climatic fluctuations has not been explored. Here we show that the landing site experienced multiple climatic changes in the Amazonian, which are recorded by an intriguing set of ridges that we interpret as Periodic Bedrock Ridges (PBRs). Clues for a PBR origin result from ridge regularity, defect terminations, and the presence of preserved megaripples detaching from the PBRs. PBR orientation differs from superimposed transverse aeolian ridges pointing toward a major change in wind regime. Our results provide constrains on PBR formation mechanisms and offer indications on paleo winds that will be crucial for understanding the landing site geology.

Megaripple Migration on Mars.

Aeolian megaripples, with 5- to 50-m spacing, are abundant on the surface of Mars. These features were repeatedly targeted by high-resolution orbital images, but they have never been observed to move. Thus, aeolian megaripples (especially the bright-toned ones often referred as Transverse Aeolian Ridges-TARs) have been interpreted as relict features of a past climate. In this report, we show evidence for the migration of bright-toned megaripples spaced 1 to 35 m (5 m on average) in two equatorial areas on Mars indicating that megaripples and small TARs can be active today. The moving megaripples display sand fluxes that are 2 orders of magnitudes lower than the surrounding dunes on average and, unlike similar bedforms on Earth, can migrate obliquely and longitudinally. In addition, the active megaripples in the two study areas of Syrtis Major and Mawrth Vallis show very similar flux distributions, echoing the similarities between dune crest fluxes in the two study areas and suggesting the existence of a relationship between dune and megaripple fluxes that can be explored elsewhere. Active megaripples, together with high-sand flux dunes, represent a key indicator of strong winds at the surface of Mars. A past climate with a denser atmosphere is not necessary to explain their accumulation and migration.

RBone volume reconstruction in atrophic edentulous ridges: placement method of graft-implant unity in single step together with endogenous growth factors.

AIM: The methods of inserting osseointegrated implants in atrophic edentulous ridges need first bone tissue graft and subsequently the insertion of fixtures. These methods need a long period of time before a prosthesis can be made: for this reason the researchers experimented different techniques to reduce times of prosthetic loading. Our experimented method makes it possible to shorten the prosthetic period notably. METHODS: During surgery an implant is inserted in the symphysis area and then it is removed by trephine bur having a diameter greater than 1 mm compared to the receiving site and by using irrigation with 4 degrees C physiological solution. After 75 days, the implant is loaded by temporary prosthesis and subsequently a final restoration is applied after 4-6 months, depending on bone quality. RESULTS: Our surgical method, in spite of being conditioned by the anatomical conformation of the edentulous ridge and anatomical limits, proved to be predictable and with the same success percentages as other surgical techniques used for morphological reconstruction of atrophic edentulous ridges, shortening prosthetic loading times notably. CONCLUSIONS: Despite the small number of patients treated and the short control period do not give enough elements to consider this new method applicable in all types of atrophies, our results confirm the validity of this technique if well used. In the future further studies and experimentations on greater number of patients and for at least 5 year follow-up are needed.

Tissue reactions, fluids, and bacterial infiltration in implants retrieved at autopsy: a case report.

A 72-year-old patient underwent the placement of 2 screw-type implants. After 5 months the patient died of a massive stroke, and a block section of the portion of the mandible containing the implants was done. The specimen was treated to obtain thin ground sections. A 1- to 5-micron gap was present between the implant and the healing cover screw, and this space was filled by bacteria and calculus; bacteria were also present in the most apical portion of the hollow part of the implant. An inflammatory infiltrate was present in the connective peri-implant tissues. The spaces between all implant components (implant, abutment, and healing screw) can act as conduits and reservoirs for bacteria, which could cause inflammation of the peri-implant soft tissues. In conclusion, the histologic data from this autopsy case may help to confirm the penetration by fluids and bacteria into the internal portion of the implants, obtained from previous in vitro and in vivo studies.

Bloodstream infections can develop late (after day 100) and/or in the absence of neutropenia in children receiving allogeneic bone marrow transplantation.

We retrospectively evaluated the incidence and time from transplantation of bloodstream infections occurring in children receiving bone marrow transplant (BMT) at G Gaslini Children's Hospital between September 1984 and December 1997. During this period the incidence was 35% after allogeneic and 26% after autologous BMT (P=0.08). Among these episodes, 38% after allogeneic BMT and 90% after autologous BMT were detected in the presence of neutropenia within the first 30 days from reinfusion (P < 0.001). Incidence of catheter-related bloodstream infections was 40% after allogeneic and 8% after autologous BMT (P < 0.001). Bloodstream infections in the absence of neutropenia were 55% after allogeneic BMT vs 10% after autologous BMT (P < 0.001) and occurred later after reinfusion (mean 199 vs 41 days, P <0.001). Among the episodes occurring after allogeneic BMT and in the absence of neutropenia, 61% were related to the presence of a central venous catheter, 15% were related to the presence of GVHD, but 23% were not associated with any of major risk factors for infection. Finally, 38% of episodes following allogeneic BMT were detected after day 100 vs 1% after autologous BMT. We concluded that patients receiving allogeneic BMT experience a high incidence of bloodstream infections in the absence of neutropenia and that a significant proportion of these episodes is not clearly associated with well known risk factors such as GVHD or central venous catheters. Moreover, many episodes develop a long time after the transplantation procedure. Therefore, any febrile episode following allogeneic BMT even late and/or in the absence of neutropenia should be intensively managed.

Topical dimethylsulfoxide for the prevention of soft tissue injury after extravasation of vesicant cytotoxic drugs: a prospective clinical study.

PURPOSE: To evaluate the activity and tolerability of dimethylsulfoxide (DMSO) in the prevention of soft tissue toxicity after extravasation of cytotoxic drugs. PATIENTS AND METHODS: From June 1991 to December 1994, all patients who had an extravasation during intravenous (IV) infusion of cytotoxic drugs in our institution were considered for an open, prospective study of preventive treatment with 99% DMSO, applied topically on the extravasation site every 8 hours for 7 days. Intermittent local cooling (for 1 hour three times daily) on the first 3 days was also used. RESULTS: One hundred forty-four patients with extravasations of doxorubicin (n = 11), epirubicin (n = 46), mitomycin (n = 5), mitoxantrone (n = 13), cisplatin (n = 44), carboplatin (n = 6), ifosfamide (n = 14), and fluorouracil (n = 5) entered the study; 127 were assessable. Only one patient suffered an ulceration. The treatment was well tolerated, with mild local burning and a characteristic breath odor being the only side effects of DMSO application, even in cases in which treatment continued for up to 6 weeks to obtain remission of the symptoms of extravasation. CONCLUSION: Topical DMSO is an effective and safe antidote that may be used with local cooling after extravasations of vesicant drugs other than those drugs for which standard interventions are defined.

[Sulodexide in the prevention of post-mastectomy lymphedema]. / Il sulodexide nella prevenzione del linfedema post-mastectomia.

Post-mastectomy lymphedema of the upper limb, that can be noticed by 10 to 20 percent of patients with breast cancer, is usually related to some risk factors: use of radiotherapy on the axilla, obesity, venous outflow obstruction, delayed wound healing or infection. The most important contributing factor to postsurgical edema is the development of lymphangitis in the upper limb. Although literature contains numerous accounts on the use of pharmacological agents for the treatment of postmastectomy lymphedema, the results are not satisfactory in term of clinical response and side effects. In the present study we investigate tolerability and feasibility of the use of suledexide in patients, submitted to mastectomy for breast cancer, with an initial lymphedema of the limb omolateral to surgery or other risk factors for the development of a clinical remarkable lymphedema. Our results show that sulodexide is a very satisfactory therapy in term of lack of side effects and good compliance.

Combined management in the treatment of epidoxorubicin extravasation. A case report.

Inadvertent extravasation during intravenous antitumor therapy is not an unusual complication and can cause damage ranging from minor erythema to severe local necrosis. The appropriate management of these iatrogenic accidents as a part of supportive care in oncology has been addressed by several experimental studies, but there has been little clinical study and no conclusive evidence on the best therapeutic strategies to adopt. The case reported here of a patient suffering from severe soft-tissue injury caused by extravasation of epidoxorubicin demonstrates the usefulness of a combined management (medical, surgical and rehabilitative) in the appropriate care of extravasation.

Hyaluronidase as an antidote to extravasation of Vinca alkaloids: clinical results.

Skin necrosis is a recognized potential consequence of an inadvertent extravasation of Vinca alkaloids in the surrounding tissues during i.v. administration. Experimental studies suggest that hyaluronidase, an enzyme that degrades hyaluronic acid and improves the absorption of locally injected drugs, can reduce the risk of progressing to skin necrosis. On this basis, we used this enzyme as a local treatment after extravasations of Vinca alkaloids in seven patients. No patient suffered from subsequent skin necrosis. To the best of our knowledge, this is the first clinical report confirming the positive findings of experimental studies on the effectiveness of this antidote.