101 research outputs found
Does Father Know Best? A Formal Model of the Paternal Influence on Childhood Social Anxiety
We explore paternal social anxiety as a specific risk factor for childhood social anxiety in a rational optimization model. In the course of human evolution, fathers specialized in external protection (e.g., confronting the external world) while mothers specialized in internal protection (e.g., providing comfort and food). Thus, children may instinctively be more influenced by the information signaled by paternal versus maternal behavior with respect to potential external threats. As a result, if fathers exhibit social anxiety, children interpret it as a strong negative signal about the external social world and rationally adjust their beliefs, thus becoming stressed. Under the assumption that paternal signals on social threats are more influential, a rational cognitive inference leads children of socially anxious fathers to develop social anxiety, unlike children of socially anxious mothers. We show in the model that mothers cannot easily compensate for anxious paternal behavior, but choose to increase maternal care to maintain the child’s wellbeing. We discuss research directions to test the proposed model as well as implications for the prevention and treatment of child social anxiety
Isolation of a Rickettsial Pathogen from a Non-Hematophagous Arthropod
Rickettsial diversity is intriguing in that some species are transmissible to vertebrates, while others appear exclusive to invertebrate hosts. Of particular interest is Rickettsia felis, identifiable in both stored product insect pests and hematophagous disease vectors. To understand rickettsial survival tactics in, and probable movement between, both insect systems will explicate the determinants of rickettsial pathogenicity. Towards this objective, a population of Liposcelis bostrychophila, common booklice, was successfully used for rickettsial isolation in ISE6 (tick-derived cells). Rickettsiae were also observed in L. bostrychophila by electron microscopy and in paraffin sections of booklice by immunofluorescence assay using anti-R. felis polyclonal antibody. The isolate, designated R. felis strain LSU-Lb, resembles typical rickettsiae when examined by microscopy. Sequence analysis of portions of the Rickettsia specific 17-kDa antigen gene, citrate synthase (gltA) gene, rickettsial outer membrane protein A (ompA) gene, and the presence of the R. felis plasmid in the cell culture isolate confirmed the isolate as R. felis. Variable nucleotide sequences from the isolate were obtained for R. felis-specific pRF-associated putative tldD/pmbA. Expression of rickettsial outer membrane protein B (OmpB) was verified in R. felis (LSU-Lb) using a monoclonal antibody. Additionally, a quantitative real-time PCR assay was used to identify a significantly greater median rickettsial load in the booklice, compared to cat flea hosts. With the potential to manipulate arthropod host biology and infect vertebrate hosts, the dual nature of R. felis provides an excellent model for the study of rickettsial pathogenesis and transmission. In addition, this study is the first isolation of a rickettsial pathogen from a non-hematophagous arthropod
The Effect of OPA1 on Mitochondrial Ca2+ Signaling
The dynamin-related GTPase protein OPA1, localized in the intermembrane space and tethered to the inner membrane of mitochondria, participates in the fusion of these organelles. Its mutation is the most prevalent cause of Autosomal Dominant Optic Atrophy. OPA1 controls the diameter of the junctions between the boundary part of the inner membrane and the membrane of cristae and reduces the diffusibility of cytochrome c through these junctions. We postulated that if significant Ca2+ uptake into the matrix occurs from the lumen of the cristae, reduced expression of OPA1 would increase the access of Ca2+ to the transporters in the crista membrane and thus would enhance Ca2+ uptake. In intact H295R adrenocortical and HeLa cells cytosolic Ca2+ signals evoked with K+ and histamine, respectively, were transferred into the mitochondria. The rate and amplitude of mitochondrial [Ca2+] rise (followed with confocal laser scanning microscopy and FRET measurements with fluorescent wide-field microscopy) were increased after knockdown of OPA1, as compared with cells transfected with control RNA or mitofusin1 siRNA. Ca2+ uptake was enhanced despite reduced mitochondrial membrane potential. In permeabilized cells the rate of Ca2+ uptake by depolarized mitochondria was also increased in OPA1-silenced cells. The participation of Na+/Ca2+ and Ca2+/H+ antiporters in this transport process is indicated by pharmacological data. Altogether, our observations reveal the significance of OPA1 in the control of mitochondrial Ca2+ metabolism
New case of trichorinophalangeal syndrome-like phenotype with a de novo t(2;8)(p16.1;q23.3) translocation which does not disrupt the TRPS1 gene
Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study
Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk
Male sterile mutant casanova gives clues to mechanisms of sperm-egg interactions in Drosophila melanogaster.
The plasma membrane of the spermatozoa of Drosophila melanogaster contains two integral proteins with glycosidase activity, beta -N-acetylglucosaminidase and alpha -D-mannosidase. Biochemical analysis and ultrastructural cytochemistry of spermatozoa of the autosomal male sterile mutant casanova reveal that at least one of these enzymes, beta -N-acetylglucosaminidase, is crucial for sperm-egg interactions. casanova sperm are motile, morphologically normal, are transferred to the female at mating, but are unable to fertilize the eggs. The mutation was localised by deficiency mapping to the chromosomal region 95E8-F7. Fluorimetric assays showed that the mutant's sperm have the same level Of alpha -D-mannosidase activity as wild-type sperm, whereas beta -N-acetylglucosaminidase activity reaches only 51% of the wild-type level. The biochemical characteristics of alpha -D-mannosidase and of the residual beta -N-acetylglucosaminidase are the same as in wild-type males. Ultrastructural localization of the enzymes indicated that casanova spermatozoa lacks beta -N-acetylglucosaminidase on the plasma membrane covering the acrosome, whereas the location of this glycosidase at the terminal part of the sperm tail is indistinguishable from the wild-type situation. The results strongly suggest that in Drosophila the beta -N-acetylglucosaminidase of the plasma membrane covering the acrosome functions as a receptor for the glycoconjugates on the egg surface. We named the putative egg receptor EROS. This is the first evidence for an egg/sperm recognition system in insects. The mechanism is similar to those known from higher animals
Plastic patterns in larval development of Endangered endemic Atelognathus patagonicus: implications for conservation strategies
Identifcation and expression profiling of Ceratitis capitata genes coding for beta-hexosaminidases
The goal of this study was to identify the genes coding for beta-N-acetylhexosaminidases in the Mediterranean fruit fly (medfly) Ceratitis capitata, one of the most destructive agricultural pests, belonging to the Tephritidae family, order Diptera. Two dimeric beta-N-acetylhexosaminidases, HEXA and HEXB, have been recently identified on Drosophila sperm. These enzymes are involved in egg binding through interactions with complementary carbohydrates on the surface of the egg shell. Three genes, Hexosaminidase I (Hexol), Hexosaminidase 2 (Hexo2) and fused lobes (fdl), encode for HEXA and HEXB subunits. The availability of C capitata EST libraries derived from embryos and adult heads allowed us to identify three sequences homologous to the D. melanogaster Hexol, Hexo2 and fdl genes. Here, we report the expression profile analysis of CcHexo1 CcHexo2 and Ccfdld in several tissues, organs and stages. Ccfdl expression was highest in heads of both sexes and in whole adult females. In the testis and ovary the three genes showed distinct spatial and temporal expression patterns. All the mRNAs were detectable in early stages of spermatogenesis; CcHexo2 and Ccfdl were also expressed in early elongating spermatid cysts. All three genes are expressed in the ovarian nurse cells. CcHexo1 and Ccfdl are stage specific, since they have been observed in stages 12 and 13 during oocyte growth, when programmed cell death occurs in nurse cells. The expression pattern of the three genes in medfly gonads suggests that, as their Drosophila counterparts, they may encode for proteins involved in gametogenesis and fertilization
Anal cancer FDG-PET standard uptake value: correlation with tumor characteristics, treatment response and survival.
The present work studies the correlation of (18) F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) standardized uptake value (SUV) with tumor characteristics, clinical response and prognosis in a series of anal canal cancer patients treated with chemo-radiotherapy. Materials and methods: Fifty-five patients were included in the present analysis. PET maximum SUV (SUVmax) of primary tumor was calculated for each patient. The correlation with clinical parameters, tumor response and survival data were analyzed. Results: SUVmax significantly correlated with T-stage (p = 0.01) and histology (p = 0.03). Median SUVmax was higher for lesions with partial response (PR, 21/55, 38 %) than for lesions with complete response (CR, 34/55, 62 %) but without statistical significance (p = 0.17). The actuarial disease-free survival (DFS) and overall survival (OS) rates were 53.0 and 77.8 % at 2 years and 41.3 and 58.6 % at 5 years, respectively. Median SUVmax did not statistically correlate with clinical response or survival. CR and T1\u2013T2 stage were statistically significant prognostic factors for disease-free survival (p < 0.0001 and p = 0.02, respectively) and CR was significant also for overall survival (p < 0.0001). Conclusions: Our data suggest that pre-treatment FDG-PET/CT SUVmax cannot directly predict tumor response and survival, but it is strongly associated with tumor characteristics such as primary tumor stage and histology, being the first one of the most important and validated prognostic factors for anal cance
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