Involvement of central nervous system disclosing Waldenstrom's disease: demonstration of intrathecal secretion of immunoglobulin M]

We report the case of a 68-year old woman complaining of disorders of memory and persistent headaches in whom the diagnosis of Waldenstr?m's macroglobulinaemia (WM) was made. Computerized tomography of the brain showed a butterfly-shaped hyperdensity in the splenium of the corpus callosum, with ventricular dilatation. Magnetic resonance imaging displayed high-intensity signals on T2-weighted sequences. Protein immunoelectrophoresis elicited an IgM kappa peak. The CSF was found to contain proteins and lymphocytes in excess, and immunohistochemical staining confirmed the predominance of anti-kappa and the presence of intrathecal IgM secretion. Chemotherapy was temporarily effective on the memory disorders, but the patient died 26 months after the beginning of treatment. Central nervous system manifestations are seldom observed in WM, and they are now grouped under the name of Bing-Neel syndrome. Psychic disorders are rarely reported. It is suggested that IgM secretion plays a predominant role in the pathogenesis of leucoencephalitis, and this is supported by the finding of intrathecal IgM synthesis.     

Muscle function and muscle balance in lower limbs are not impaired in individuals with general joint hypermobility

Sport Sciences for Health - The generalized joint hypermobility (GJH) syndrome is a condition characterized by a connective tissue disorder that may negatively affect the muscle function and muscle...     

Thoracoscopic surgery in elderly lung cancer patients

Age is a recognized risk factor for death after thoracotomy in elderly patients with lung cancer. Among other factors, the genesis of this risk is the physiologic debilitation that occurs after division of the intrathoracic respiratory muscles during thoracotomy, as well as the loss of lung tissue after lung resection. Recent advances in video-assisted thoracic surgery (VATS) techniques provide an alternative to standard thoracotomy in elderly lung cancer patients, resulting in decreased recovery times and fewer perioperative complications. Likewise, smaller lung resections (VATS-guided limited wedge resection versus lobectomy with thoracotomy) can be adequate oncologic procedures in patients with a limited life expectancy but resectable disease. We studied these alternative procedures in a cohort of thoracic surgical patients at the Brigham and Women's Hospital in Boston, MA. Proposed investigations of the psychosocial implications of thoracic surgery in the elderly, irrespective of the safety of these maneuvers, are addressed.     

Buccal lymphomatoid granulomatosis

A 57 year old man was referred to us with multiple long-standing, recurring and refractory mouth ulcers involving the palate, the intermaxillary folds, the inner side of the cheeks, the frenum of the tongue, a tonsil, the pharynx, the gums and a lower lip. Multiple biopsies had excluded a lymphoma, a carcinoma and infection. A new biopsy showed a polymorphous granuloma with up to 40% of atypical lymphoid cells. No angiitis was present, but an angiocentric pattern was present in the granuloma. The atypical cells stained positively with OKT3 and OKT4 antisera. The patient also had cardiac rhythm disturbances with defects on the myocardial scan and a proteinuria. Thus, we suspected the diagnosis of lymphomatoid granulomatosis, although there were no pulmonary nodules. Cyclophosphamide and prednisone were given with immediate success. As the doses were gradually decreased, a small relapse occurred. It was controlled by increasing the cyclophosphamide dosage for six months. The patient is now in complete remission more than four years after having discontinued the treatment. Thus, lymphomatoid granulomatosis can be diagnosed on the basis of a biopsy of buccal ulcers and in the absence of the classical pulmonary nodules. We found no evidence that the atypical cells were lymphomatous; rather, the very good response to the treatment points to a curable granulomatosis.     

Barriers to physical activity during the COVID-19 pandemic in adults: a cross-sectional study

Sport Sciences for Health - Social isolation due to the coronavirus disease 2019 (COVID-19) pandemic has reduced physical activity levels in both men and women. The identification of barriers to...     

Engram Size Varies with Learning and Reflects Memory Content and Precision

Memories are rarely acquired under ideal conditions, rendering them vulnerable to profound omissions, errors, and ambiguities. Consistent with this, recent work using context fear conditioning has shown that memories formed after inadequate learning time display a variety of maladaptive properties, including overgeneralization to similar contexts. However, the neuronal basis of such poor learning and memory imprecision remains unknown. Using c-fos to track neuronal activity in male mice, we examined how these learning-dependent changes in context fear memory precision are encoded in hippocampal ensembles. We found that the total number of c-fos-encoding cells did not correspond with learning history but instead more closely reflected the length of the session immediately preceding c-fos measurement. However, using a c-fos-driven tagging method (TRAP2 mouse line), we found that the degree of learning and memory specificity corresponded with neuronal activity in a subset of dentate gyrus cells that were active during both learning and recall. Comprehensive memories acquired after longer learning intervals were associated with more double-labeled cells. These were preferentially reactivated in the conditioning context compared with a similar context, paralleling behavioral discrimination. Conversely, impoverished memories acquired after shorter learning intervals were associated with fewer double-labeled cells. These were reactivated equally in both contexts, corresponding with overgeneralization. Together, these findings provide two surprising conclusions. First, engram size varies with learning. Second, larger engrams support better neuronal and behavioral discrimination. These findings are incorporated into a model that describes how neuronal activity is influenced by previous learning and present experience, thus driving behavior.SIGNIFICANCE STATEMENT Memories are not always formed under ideal circumstances. This is especially true in traumatic situations, such as car accidents, where individuals have insufficient time to process what happened around them. Such memories have the potential to overgeneralize to irrelevant situations, producing inappropriate fear and contributing to disorders, such as post-traumatic stress disorder. However, it is unknown how such poorly formed fear memories are encoded within the brain. We find that restricting learning time results in fear memories that are encoded by fewer hippocampal cells. Moreover, these fewer cells are inappropriately reactivated in both dangerous and safe contexts. These findings suggest that fear memories formed at brief periods overgeneralize because they lack the detail-rich information necessary to support neuronal discrimination.