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A preliminary description is presented of the well-preserved frozen mummies of two cubs of the extinct cave lion Panthera spelaea (finds of 2017–2018, Semyuelyakh River, Yakutia, eastern Siberia, Russia). The fossil lion cubs were found in close proximity, but they do not belong to the same litter, since their radiocarbon ages differ: the female (named ‘Sparta’) was dated to 27,962 ± 109 uncal years BP, and the male (named ‘Boris’) was dated to 43,448 ± 389 uncal years BP. The lion cubs have similar individual ages, 1–2 months. The general tone of the colour of the fur coat of Sparta is greyish to light brown, whereas, in Boris, the fur is generally lighter, greyish yellowish. It is, therefore, possible that light colouration prevailed with age in cave lions and was adaptive for northern snow-covered landscapes. The article discusses the results of computed tomography of cubs of the cave lion, the possible reasons for their death, and the peculiarities of their existence in the Siberian Arctic.

The article puts together the contributions of fourteen researchers, specialists of the most diverse sectors of the African archaeology (palaeolithic industries, néolithisation, history of the breeding, rock art, emergence of the complex societies, ferrous metallurgy, developments of soils, on concerning subjects of regions very contrasted and scattered on the whole continent (South Africa, East Africa, Western Africa, Sahara, Maghreb). Its coherence finds its origins in the prejudice to centre the general reflection on the study of the socio-economic variability, in the time and in the space. Through the consideration of elements of this surprising mosaic, it is a question of wondering about the nature of the answers brought by the human groups confronted with the gnawing environments (pressure of the natural surroundings, socioeconomic relations, cultural and historic frames. Africa considered through these diverse facets thus becomes, for the authors, the major laboratory of reflection for the establishment of a reliable documentation on the crucial problem of the complexity of the relations between the Man and its environment.

El Pirineo francés y Cantabria presentan analogías en las muestras paleontológicas, tanto a nivel biocronológico como antropozoologico. Por eso, estas dos regiones -que contienen abundantes yacimientos pleistocenos-, presentan un modelo de ocupación y de explotación de zonas de montañas comparable, con ocupaciones humanas principalmente posteriores al Eemiense y generalmente implantadas en contexto ursino. A partir del Paleolítico Superior Medio una explotación más diversificada de recursos animales (caza selectiva, actividades industriales y artisticas) parece más evidente. Se presenta aqui un esquema general de procesos de ocupación del Pirineo francés con comparaciones inter-regionales con numerosos elementos de reflexión arqueozoológicos y tafonómicos.

Introduction Lymphoedema is a chronic condition caused by lymphatic insufficiency. It leads to swelling of the limb/midline region and an increased risk of infection. Lymphoedema is often associated with mental and physical problems limiting quality of life. The first choice of treatment is a conservative treatment, consisting of exercises, skin care, lymph drainage and compression. Reconstructive lymphatic surgery is also often performed, that is, lymphovenous anastomoses, lymph node transfer or a combination. However, robust evidence on the effectiveness of reconstructive lymphatic surgery is missing. Therefore, the objective of this trial is to investigate the added value of reconstructive lymphatic surgery to the conservative treatment in patients with lymphoedema.Methods and analysis A multicentre randomised controlled and pragmatic trial was started in March 2022 in three Belgian university hospitals. 90 patients with arm lymphoedema and 90 patients with leg lymphoedema will be included. All patients are randomised between conservative treatment alone (control group) or conservative treatment with reconstructive lymphatic surgery (intervention group). Assessments are performed at baseline and at 1, 3, 6, 12, 18, 24 and 36 months. The primary outcome is lymphoedema-specific quality of life at 18 months. Key secondary outcomes are limb volume and duration of wearing the compression garment at 18 months. The approach of reconstructive lymphatic surgery is based on presurgical investigations including clinical examination, lymphofluoroscopy, lymphoscintigraphy, lymph MRI or CT angiography (if needed). All patients receive conservative treatment during 36 months, which is applied by the patient’s own physical therapist and by the patient self. From months 7 to 12, the hours a day of wearing the compression garment are gradually decreased.Ethics and dissemination The study has been approved by the ethical committees of University Hospitals Leuven, Ghent University Hospital and CHU UCL Namur. Results will be disseminated via peer-reviewed journals and presentations.Trial registration number NCT05064176

Since the emergence of microsurgery in reconstructive surgery, free flaps have become a key tool in the management of patients with breast cancer. One such flap is the profunda artery perforator (PAP) flap. To date, there is no scientific consensus on whether voluminous free flaps remain dependent on their vascular pedicle throughout their lifespan. Therefore, the pedicle should always be carefully protected during revision surgery. In this article, we review the case of a middle-aged woman who suffered a pedicle transection needing re-anastomosis during revision surgery six months after free-flap breast reconstruction. A 52-year-old woman who noticed a firm nodule in her right breast and armpit was referred to our department for surgical management. The Caucasian woman presented with no significant medical history or symptoms at the first consultation. Ultrasound-guided biopsy confirmed an invasive grade III lobular carcinoma. Following staging, the patient underwent neoadjuvant chemotherapy before a right mastectomy with a complete homolateral axillary lymph node dissection and postoperative radiotherapy. One year after completing radiotherapy, free flap reconstruction with a PAP flap was performed, and six months later, revision surgery was required to enhance the volume of the reconstructed breast with a tissue expander and later an implant. Unfortunately, pedicle transection occurred during revision surgery, causing complete devascularization of the flap, which was confirmed by intraoperative Indocyanine Green imaging. The authors elected to perform salvage re-anastomosis during the surgery. In keeping with the author’s 23-year experience with free flaps, the vascular pedicle should always be preserved in voluminous free flaps, as neovascularization alone may not ensure whole flap survival. The authors suggest always attempting re-anastomosis if vessels are compromised during revision surgery.

Retroviruses package two copies of their genomic RNA (gRNA) as non-covalently linked dimers. Many studies suggest that the retroviral nucleocapsid protein (NC) plays an important role in gRNA dimerization. The upper part of the L3 RNA stem-loop in the 5′ leader of the avian leukosis virus (ALV) is converted to the extended dimer by ALV NC. The L3 hairpin contains three stems and two internal loops. To investigate the roles of internal loops and stems in the NC-mediated extended dimer formation, we performed site-directed mutagenesis, gel electrophoresis, and analysis of thermostability of dimeric RNAs. We showed that the internal loops are necessary for efficient extended dimer formation. Destabilization of the lower stem of L3 is necessary for RNA dimerization, although it is not involved in the linkage structure of the extended dimer. We found that NCs from ALV, human immunodeficiency virus type 1 (HIV-1), and Moloney murine leukemia virus (M-MuLV) cannot promote the formation of the extended dimer when the apical stem contains ten consecutive base pairs. Five base pairs correspond to the maximum length for efficient L3 dimerization induced by the three NCs. L3 dimerization was less efficient with M-MuLV NC than with ALV NC and HIV-1 NC.

The HIV-1 nucleocapsid protein (NC) is a small basic protein containing two zinc fingers (ZF) separated by a short linker. It is involved in several steps of the replication cycle and acts as a nucleic acid chaperone protein in facilitating nucleic acid strand transfers occurring during reverse transcription. Recent analysis of three-dimensional structures of NC-nucleic acids complexes established a new property: the unpaired guanines targeted by NC are more often inserted in the C-terminal zinc finger (ZF2) than in the N-terminal zinc finger (ZF1). Although previous NMR dynamic studies were performed with NC, the dynamic behavior of the linker residues connecting the two ZF domains remains unclear. This prompted us to investigate the dynamic behavior of the linker residues. Here, we collected 15N NMR relaxation data and used for the first time data at several fields to probe the protein dynamics. The analysis at two fields allows us to detect a slow motion occurring between the two domains around a hinge located in the linker at the G35 position. However, the amplitude of motion appears limited in our conditions. In addition, we showed that the neighboring linker residues R29, A30, P31, R32, K33 displayed restricted motion and numerous contacts with residues of ZF1. Our results are fully consistent with a model in which the ZF1-linker contacts prevent the ZF1 domain to interact with unpaired guanines, whereas the ZF2 domain is more accessible and competent to interact with unpaired guanines. In contrast, ZF1 with its large hydrophobic plateau is able to destabilize the double-stranded regions adjacent to the guanines bound by ZF2. The linker residues and the internal dynamics of NC regulate therefore the different functions of the two zinc fingers that are required for an optimal chaperone activity.

HIV-1 nucleocapsid protein (NC) is involved in the rearrangement of nucleic acids occurring in key steps of reverse transcription. The protein, through its two zinc fingers, interacts preferentially with unpaired guanines in single-stranded sequences. In mini-cTAR stem-loop, which corresponds to the top half of the cDNA copy of the transactivation response element of the HIV-1 genome, NC was found to exhibit a clear preference for the TGG sequence at the bottom of mini-cTAR stem. To further understand how this site was selected among several potential binding sites containing unpaired guanines, we probed the intrinsic dynamics of mini-cTAR using (13)C relaxation measurements. Results of spin relaxation time measurements have been analyzed using the model-free formalism and completed by dispersion relaxation measurements. Our data indicate that the preferentially recognized guanine in the lower part of the stem is exempt of conformational exchange and highly mobile. In contrast, the unrecognized unpaired guanines of mini-cTAR are involved in conformational exchange, probably related to transient base-pairs. These findings support the notion that NC preferentially recognizes unpaired guanines exhibiting a high degree of mobility. The ability of NC to discriminate between close sequences through their dynamic properties contributes to understanding how NC recognizes specific sites within the HIV genome.