378 research outputs found

    Testing evolutionary models of senescence in a natural population: age and inbreeding effects on fitness components in song sparrows

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    Mutation accumulation (MA) and antagonistic pleiotropy (AP) have each been hypothesized to explain the evolution of ‘senescence’ or deteriorating fitness in old age. These hypotheses make contrasting predictions concerning age dependence in inbreeding depression in traits that show senescence. Inbreeding depression is predicted to increase with age under MA but not under AP, suggesting one empirical means by which the two can be distinguished. We use pedigree and life-history data from free-living song sparrows (Melospiza melodia) to test for additive and interactive effects of age and individual inbreeding coefficient (f) on fitness components, and thereby assess the evidence for MA. Annual reproductive success (ARS) and survival (and therefore reproductive value) declined in old age in both sexes, indicating senescence in this short-lived bird. ARS declined with f in both sexes and survival declined with f in males, indicating inbreeding depression in fitness. We observed a significant age×f interaction for male ARS (reflecting increased inbreeding depression as males aged), but not for female ARS or survival in either sex. These analyses therefore provide mixed support for MA. We discuss the strengths and limitations of such analyses and therefore the value of natural pedigreed populations in testing evolutionary models of senescence

    First-in-man craniectomy and asportation of solitary cerebellar metastasis in COVID-19 patient: A case report

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    Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak has an impact on the delivery of neurosurgical care, and it is changing the perioperative practice worldwide. We present the first case in the literature of craniectomy procedure and asportation of a solitary cerebellar metastasis of the oesophagus squamous carcinoma in a 77 years old woman COVID-19 positive. In these particular circumstances, we show that adequate healthcare resources and risk assessments are essential in the management of COVID-19 patients referred to emergency surgery. Presentation of case: The case here presented was treated in 2019 for squamous carcinoma of the oesophagus. In April 2020, she presented a deterioration of her clinical picture consisting of dysphagia, abdominal pain, hyposthenia and ataxia. A Head CT scan was performed, which showed the presence of a solitary cerebellar metastasis. Her associated SARS-CoV-2 positivity status represented the principal clinical concern throughout her hospitalisation. Discussion: The patient underwent a suboccipital craniectomy procedure with metastasis asportation. She tested positive for SARS-CoV-2 in the pre- and post-operative phases, but she was not admitted to the intensive care unit because she did not present any respiratory complications. Her vital parameters and inflammation indexes fell within the reference ranges, and she was kept in isolation for 16 days in our neurosurgical unit following strict COVID-19 measures. She was asymptomatic and not treated for any of the specific and non-specific symptoms of COVID-19. Conclusion: This is the first case reported of solitary cerebellar metastasis of oesophagus carcinoma operated on a COVID-19 positive patient. It shows that asymptomatic COVID-19 positive patients can undergo major emergency surgeries without the risk of infecting the operating team if adequate Personal Protection Equipment (PPE) is used. The patient remained asymptomatic and did not develop the disease's active phase despite undergoing a stressful event such as a major emergency neurosurgical procedure. In the current crisis, a prophylactic COVID-19 screening test can identify asymptomatic patients undergoing major emergency surgery and adequate resource planning and Personal Protective Equipment (PPE) for healthcare workers can minimise the effect of the COVID-19 pandemic

    Fitness Correlates Of Song Repertoire Size In Free-Living Song Sparrows (Melospiza Melodia)

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    Models of sexual selection propose that exaggerated secondary sexual ornaments indicate a male\u27s own fitness and the fitness of his offspring. These hypotheses have rarely been thoroughly tested in free-living individuals because overall fitness, as opposed to fitness components, is difficult to measure. We used 20 years of data from song sparrows ( Melospiza melodia) inhabiting Mandarte Island, British Columbia, Canada, to test whether a male\u27s song repertoire size, a secondary sexual trait, predicted overall measures of male or offspring fitness. Males with larger song repertoires contributed more independent and recruited offspring, and independent and recruited grandoffspring, to Mandarte\u27s population. This was because these males lived longer and reared a greater proportion of hatched chicks to independence from parental care, not because females mated to males with larger repertoires laid or hatched more eggs. Furthermore, independent offspring of males with larger repertoires were more likely to recruit and then to leave more grandoffspring than were offspring of males with small repertoires. Although we cannot distinguish whether observed fitness variation reflected genetic or environmental effects on males or their offspring, these data suggest that female song sparrows would gain immediate and intergenerational fitness benefits by pairing with males with large song repertoires

    Killer cell Immunoglobulin-like receptor-ligand matching and outcomes after unrelated cord blood transplantation in acute myeloid leukemia

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    The effect of killer cell immunoglobulin-like receptor (KIR)-ligand matching on outcomes after unrelated cord blood (CB) transplantation was studied in 461 patients with acute myeloid leukemia, categorizing KIR ligand for HLA-C groups C1 and C2 and Bw4. Donor-recipient HLA matching considered allele-level matching at HLA-A, -B, -C, and -DRB1. Separate analyses were conducted for 6-7/8 HLA-matched and 3-5/8 HLA-matched transplants because HLA matching confounded KIR-ligand matching (ie, KIR-ligand mismatching was less likely with better HLA matching). All patients received single CB unit and myeloablative conditioning. There were no significant differences in nonrelapse mortality (NRM), relapse, and overall mortality by KIR-ligand match status. However, among recipients of 3-5/8 HLA-matched transplants, NRM (HR, 2.26; P = .008) and overall mortality (HR, 1.78; P = .008) but not relapse were higher with KIR-ligand mismatched (host-versus-graft direction) compared with KIR-ligand matched transplants. These data do not support selecting CB units based on KIR-ligand match status for transplants mismatched at 1 or 2 HLA loci. Although transplants mismatched at 3 or more HLA loci are not recommended, avoiding KIR-ligand mismatching in this setting lowers mortality risks

    Haploidentical, unmanipulated,G-CSF primed bona marrow transplantation for patients with high risk hematological malignancies

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    Eighty patients with high-risk hematologic malignancies underwent unmanipulated, G-CSF–primed BM transplantation from an haploidentical family donor. Patients were transplanted in first or second complete remission (CR, standard-risk: n =45) or in > second CR or active disease (high-risk: n =35). The same regimen for GVHD prophylaxis was used in all cases. The cumulative incidence (CI) of neutrophil engraftment was 93% 0.1%. The 100-day CIs for II-IV and III-IV grade of acute GVHD were 24% 0.2% and 5% 0.6%, respectively. The 2-year CI of extensive chronic GVHD was 6% 0.1%. The 1-year CI of treatment-related mortality was 36% 0.3%. After a median follow-up of 18 months, 36 of 80 (45%) patients are alive in CR. The 3-year probability of overall and disease-free survival for standard-risk and high-risk patients was 54% 8% and 33% 9% and 44% 8% and 30% 9%, respectively. In multivariate analysis, disease-free survival was significantly better for patients who had standard-risk disease and received transplantations after 2007. We conclude that unmanipulated, G-CSF–primed BM transplantation from haploidentical family donor provides very encouraging results in terms of engraftment rate, incidence of GVHD and survival and represents a feasible, valid alternative for patients with high-risk malignant hematologic diseases, lacking an HLA identical sibling and in need to be urgently transplanted

    Haploidentical related donor compared to HLA-identical donor transplantation for chemosensitive Hodgkin lymphoma patients

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    Background: Allogeneic stem cell transplantation from haploidentical donor using an unmanipulated graft and post-transplantation cyclophosphamide (PT-Cy) is growing. Haploidentical transplantation with PT-Cy showed a major activity in Hodgkin lymphoma (HL), reducing the relapse incidence. The most important predictive factor of survival and toxicity was disease status before transplantation, which was better in patients with well controlled disease. Methods: We included 198 HL in complete (CR) or partial remission (PR) before transplantation. Sixty-five patients were transplanted from haploidentical donor and 133 from a HLA identical donor (both sibling and unrelated donors). Survival analysis was defined according to the EBMT criteria. Survival curves were generated by using Kaplan-Meier method and differences between groups were compared by the log rank test or by the log rank test for trend when appropriated. Results: The PFS, OS, and RI were significantly better in patients in CR compared to PR (55% vs 29% p = 0.001, 74% vs 55% p = 0.03, 27% vs 55% p < 0.001, respectively). The 2-year PFS was significantly better for HAPLO than HLA-id (63% vs 37%, p = 0.03), without difference in OS. The 1-year NRM was not different. The 2-year relapse incidence (RI) was lower in the HAPLO group (24% vs 44%, p = 0.008). Patients in CR receiving haplo HSCT showed higher 2-year PFS and lower 2-year RI than those allografted with HLA-id donor (75% vs 47%, p < 0.001 and 11% vs 34%, p < 0.001, respectively). In multivariate analysis, donor type and disease status before transplantation were independent predictors of PFS as well as they predict the risk of relapse. Disease status at transplantation and age were independently associated to OS. Conclusions: Nonetheless this is a retrospective study, limiting the wide applicability of results, data from this analysis suggest that HLA mismatch can induce a strong graft versus lymphoma effect leading to an enhanced PFS
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