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91.
Background

Incisional hernia (IH) may occur in 20% of patients after laparotomy. The hernia sac volume may be of significance, with reintegration of visceral contents potentially leading to repair failure or abdominal compartment syndrome. The present study aimed to evaluate a two-step surgical strategy comprising right colectomy for hernia reduction with synchronous absorbable mesh repair followed by definitive non-absorbable mesh repair in recurrence.

Methods

Patients operated between 2012 and 2017 at two university centers were retrospectively included. Volumetric evaluation of the IH was performed by CT imaging.

Results

Eleven patients were included. The mean BMI was 43 kg/m2 (23–52 kg/m2). Progressive preoperative pneumoperitoneum was performed in 82% of patients, with complications in 22%. The mean volumetric ratio of the volume of the hernia to the volume of the abdominal cavity was 70% (48–100%). The first parietal repair was performed using an synthetic absorbable mesh (36%), a biologic mesh (27%), or a slowly absorbable mesh (36%). No patients died as a result of the procedure. Seven (64%) patients developed grade III–IV complications, including one case of an anastomotic fistula. Recurrence occurred in eight (73%) patients after the first repair. Of these, four (50%) patients were reoperated using a non-absorbable mesh, leading to solid repair in 75% of cases. After 27 ± 18 months of follow-up, the residual IH rate was 46%.

Conclusions

Right colectomy for volume reduction in IH with loss of domain potentially represents an appropriate salvage option, supporting bowel reintegration and temporary hernia repair with absorbable material.

  相似文献   
92.
93.
Neuroticism involves a tendency for enhanced emotional and cognitive processing of negative affective stimuli and a propensity to worry and be anxious. It is known that this trait modulates fear learning and the activation of brain regions involved in it such as the amygdala, hippocampus, and prefrontal cortex and their connectivity. Thirty-nine (21 female) 14-year-old healthy adolescents participated in functional magnetic resonance imaging (fMRI) of aversive pavlovian differential delay conditioning. An unpleasant sound served as unconditioned stimulus (US) and pictures of neutral male faces as conditioned stimuli (CS+ followed by the US in 50% of the cases; CS− never followed by the US). During acquisition (CS+/− differentiation), higher levels of neuroticism were associated with a stronger interaction between the right amygdala and the right hippocampus as well as the right amygdala and prefrontal cortical regions, specifically ventromedial prefrontal cortex, dorsolateral prefrontal cortex, and anterior cingulate cortex. The association of stronger conditionability of fear and connectivity of brain regions related to consolidation of fear associations and neuroticism points to underlying mechanisms of the enhanced propensity for anxiety disorders in highly neurotic participants. This is especially important in adolescence, a vulnerable time for the onset of mental disorders such as anxiety disorders.  相似文献   
94.
We analyzed herein whether members of the tetraspanin superfamily are involved in human immature dendritic cell (DC) functions such as foreign antigen internalization, phagocytosis, and cell migration. We show that CD63, CD9, CD81, CD82, and CD151 are present in immature DCs. Whereas CD9 and CD81 are mostly expressed at the cell surface, CD63 and CD82 are also located in intracellular organelles. Complexes of monoclonal antibody (Mab) FC-5.01-CD63 or Fab-5.01-CD63 were rapidly translocated "outside-in" and followed the endocytic pathway through early endosomes and lysosomes, reaching major histocompatibility complex (MHC) class II-enriched compartments (MIICs) in less than one hour. Internalization of CD63 was also observed during Saccharomyces cerevisiae phagocytosis. Moreover, an association of CD63 with the beta-glycan receptor dectin-1 was observed. Mabs against CD9, CD63, CD81, and CD82 enhanced by 50% the migration induced by the chemokines macrophage inflammatory protein-5 (MIP-5) and MIP-1alpha. Concomitantly, Mabs against CD63 and CD82 diminished the surface expression of CD29, CD11b, CD18, and alpha5 integrins. By immunoprecipitation experiments we found that CD63 associated with integrins CD11b and CD18. These results suggest that CD9, CD63, CD81, and CD82 could play a role in modulating the interactions between immature DCs and their environment, slowing their migratory ability. However, only CD63 would intervene in the internalization of complex antigens.  相似文献   
95.
We analyzed the presenting features and survival in 1689 patients with multiple myeloma aged younger than 50 years compared with 8860 patients 50 years of age and older. Of the total 10 549 patients, 7765 received conventional therapy and 2784 received high-dose therapy. Young patients were more frequently male, had more favorable features such as low International Staging System (ISS) and Durie-Salmon stage as well as less frequently adverse prognostic factors including high C-reactive protein (CRP), low hemoglobin, increased serum creatinine, and poor performance status. Survival was significantly longer in young patients (median, 5.2 years vs 3.7 years; P < .001) both after conventional (median, 4.5 years vs 3.3 years; P < .001) or high-dose therapy (median, 7.5 years vs 5.7 years; P = .04). The 10-year survival rate was 19% after conventional therapy and 43% after high-dose therapy in young patients, and 8% and 29%, respectively, in older patients. Multivariate analysis revealed age as an independent risk factor during conventional therapy, but not after autologous transplantation. A total of 5 of the 10 independent risk factors identified for conventional therapy were also relevant for autologous transplantation. After adjusting for normal mortality, lower ISS stage and other favorable prognostic features seem to account for the significantly longer survival of young patients with multiple myeloma with age remaining a risk factor during conventional therapy.  相似文献   
96.
97.
The human anterior cingulate cortex (ACC), which is active during conflict-monitoring tasks, is thought to participate with prefrontal cortices in a distributed network for conscious self-regulation. This hypothesis predicts that conflict-related ACC activation should occur only when the conflicting stimuli are consciously perceived. To dissociate conflict from consciousness, we measured the behavioral and brain imaging correlates of a motor conflict induced by task-irrelevant subliminal or conscious primes. The same task was studied in normal subjects and in patients with schizophrenia in whom the ACC and prefrontal cortex are thought to be dysfunctional. Conscious, but not subliminal, conflict affected anterior cingulate activity in normal subjects. Furthermore, patients with schizophrenia, who exhibited a hypoactivation of the ACC and other frontal, temporal, hippocampal, and striatal sites, showed impaired conscious priming but normal subliminal priming. Those findings suggest that subliminal conflicts are resolved without ACC contribution and that the ACC participates in a distributed conscious control network that is altered in schizophrenia.  相似文献   
98.
Oncogenic activation of tyrosine kinase signaling pathway is recurrent in human leukemia. To gain insight into the oncogenic process leading to acute megakaryoblastic leukemia (AMKL), we performed sequence analyses of a subset of oncogenes known to be activated in human myeloid and myeloproliferative disorders. In a series of human AMKL samples from both Down syndrome and non-Down syndrome patients, mutations were identified within KIT, FLT3, JAK2, JAK3, and MPL genes, with a higher frequency in DS than in non-DS patients. The novel mutations were analyzed using BaF3 cells, showing that JAK3 mutations were activating mutations. Finally, we report a novel constitutively active MPL mutant, MPLT487A, observed in a non-Down syndrome childhood AMKL that induces a myeloproliferative disease in mouse bone marrow transplantation assay.  相似文献   
99.

Background

While drinking alcohol, one must choose between the immediate rewarding effects and the delayed reward of a healthier lifestyle. Individuals differ in their devaluation of a delayed reward based on the time required to receive it, i.e., delay discounting (DD). Previous studies have shown that adolescents discount more steeply than adults and that steeper DD is associated with heavier alcohol use in both groups.

Methods

In a large-scale longitudinal study, we investigated whether higher rates of DD are an antecedent or a consequence of alcohol use during adolescent development. As part of the IMAGEN project, 2220 adolescents completed the Monetary Choice Questionnaire as a DD measure, the Alcohol Use Disorders Identification Test, and the Timeline Follow Back interview at ages 14, 16, 18, and 22. Bivariate latent growth curve models were applied to investigate the relationship between DD and drinking. To explore the consequences of drinking, we computed the cumulative alcohol consumption and correlated it with the development of discounting. A subsample of 221 participants completed an intertemporal choice task (iTeCh) during functional magnetic resonance imaging at ages 14, 16, and 18. Repeated-measures ANOVA was used to differentiate between high-risk and low-risk drinkers on the development of neural processing during intertemporal choices.

Results

Overall, high rates of DD at age 14 predicted a greater increase in drinking over 8 years. In contrast, on average, moderate alcohol use did not affect DD from ages 14 to 22. Of note, we found indicators for less brain activity in top-down control areas during intertemporal choices in the participants who drank more.

Conclusions

Steep DD was shown to be a predictor rather than a consequence of alcohol use in low-level drinking adolescents. Important considerations for future longitudinal studies are the sampling strategies to be used and the reliability of the assessments.
  相似文献   
100.
OBJECTIVE: Pulmonary endothelial dysfunction is intertwined with the development and progression of pulmonary arterial hypertension (PAH). Pulmonary endothelium is an active metabolic tissue in healthy human subjects. This study was undertaken to determine the effects of PAH on pulmonary endothelial angiotensin-converting enzyme (ACE) activity and to identify differences between common PAH types, i.e., PAH related to connective tissue disease (PAH-CTD) versus idiopathic PAH (IPAH). METHODS: Nineteen patients with PAH-CTD, 25 patients with IPAH, and 23 control subjects were evaluated. The single-pass transpulmonary percent metabolism (%M) and hydrolysis (both reflecting enzyme activity per capillary) of an ACE synthetic substrate were determined. In addition, the calculated functional capillary surface area (FCSA), normalized to body surface area (BSA), was determined. RESULTS: The %M values in patients with PAH-CTD (mean+/-SEM 53.6+/-3.6%) were significantly reduced compared with those in control subjects (P<0.01) and those in patients with IPAH (P<0.03), but were similar between the IPAH and control groups (mean+/-SEM 66.2+/-3.6% and 74.7+/-2.7%, respectively). Substrate hydrolysis was also significantly reduced in patients with PAH-CTD. The FCSA/BSA was significantly reduced in patients with PAH-CTD (mean+/-SEM 1,068+/-118 ml/minute/m2) and in patients with IPAH (1,443+/-186 ml/minute/m2) compared with that in controls (2,948+/-245 ml/minute/m2; P<0.01 for both). At a given cardiac index, the FCSA/BSA tended to be lower in the PAH-CTD group than in the IPAH group. Moreover, unlike in IPAH, a linear relationship between the FCSA/BSA and the diffusing capacity for carbon monoxide (DLCO) was observed in PAH-CTD (r=0.54, P<0.03). CONCLUSION: The metabolically functional pulmonary capillary bed appears to be reduced to an equal extent in PAH-CTD and IPAH. However, %M and hydrolysis appear to be reduced in PAH-CTD but not in IPAH, reflecting relatively diminished ACE activity on the pulmonary capillary endothelial cells of patients with PAH-CTD, and showing that pulmonary endothelial metabolic function differs between PAH types. This study also provides the first functional evidence that a reduced DLCO value in patients with PAH-CTD is related to the degree of FCSA loss.  相似文献   
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