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1.
Frugivorous and nectarivorous bats rely largely on hepatic glycogenesis and glycogenolysis for postprandial blood glucose disposal and maintenance of glucose homeostasis during short time starvation, respectively. The glycogen synthase 2 encoded by the Gys2 gene plays a critical role in liver glycogen synthesis. To test whether the Gys2 gene has undergone adaptive evolution in bats with carbohydrate-rich diets in relation to their insect-eating sister taxa, we sequenced the coding region of the Gys2 gene in a number of bat species, including three Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our results showed that the Gys2 coding sequences are highly conserved across all bat species we examined, and no evidence of positive selection was detected in the ancestral branches leading to OWFBs and NWFBs. Our explicit convergence test showed that posterior probabilities of convergence between several branches of OWFBs, and the NWFBs were markedly higher than that of divergence. Three parallel amino acid substitutions (Q72H, K371Q, and E666D) were detected among branches of OWFBs and NWFBs. Tests for parallel evolution showed that two parallel substitutions (Q72H and E666D) were driven by natural selection, while the K371Q was more likely to be fixed randomly. Thus, our results suggested that the Gys2 gene has undergone parallel evolution on amino acid level between OWFBs and NWFBs in relation to their carbohydrate metabolism.  相似文献   
2.
Glioma is a huge threat for human being because it was hard to be completely removed owing to both the infiltrating growth of glioma cells and integrity of blood brain barrier. Thus effectively imaging the glioma cells may pave a way for surgical removing of glioma. In this study, a fluorescent probe, Cy3, was anchored onto the terminal of AS1411, a glioma cell targeting aptamer, and then TGN, a BBB targeting peptide, was conjugated with Cy3-AS1411 through a PEG linker. The production, named AsT, was characterized by gel electrophoresis, 1H NMR and FTIR. In vitro cellular uptake and glioma spheroid uptake demonstrated the AsT could not only be uptaken by both glioma and endothelial cells, but also penetrate through endothelial cell monolayer and uptake by glioma spheroids. In vivo, AsT could effectively target to glioma with high intensity. In conclusion, AsT could be used as an effective glioma imaging probe.  相似文献   
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In the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery, their effectiveness and safety have since been demonstrated to extend to a wide array of procedures. Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site in order to achieve hemostasis. However, many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. This subanalysis compares the safety and effectiveness of a fibrin sealant versus an absorbable hemostat for achieving hemostasis during urologic procedures with mild to moderate bleeding.Key words: Hemostasis, Hemostatics, Fibrin tissue adhesive, Urologic surgical procedures, Surgical techniqueIn the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery,1 their effectiveness and safety have since been demonstrated to extend to a wide array of procedures, including cardiovascular, gastrointestinal, pneumothoracic, neurologic, urologic, otolaryngologic, dental, and reconstructive surgeries.2,3 Within the field of urology, fibrin sealants have been used to manage bleeding from renal trauma,4 as well as to facilitate hemostasis during renal surgeries, including partial nephrectomies.57Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site (TBS) in order to achieve hemostasis.3 Many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. For example, in an observational study (N = 4374), the antifibrinolytic aprotinin was associated with an increased risk of long-term mortality within 5 years following coronary artery bypass graft surgery.8 Furthermore, repeated exposure to aprotinin may lead to allergic or potentially fatal anaphylactic reactions.911 For this reason, the US Food and Drug Administration (FDA) issued an alert in 2006 indicating that caution should be used when using aprotinin in patients with a history of previous exposure to the product.12 Tranexamic acid, another antifibrinolytic present in some commercial fibrin sealants, has been associated with alterations in neural tissue growth and adherence.13 Because of the risk of cerebral neurologic toxicity, fibrin sealants containing tranexamic acid are contraindicated for use in neurosurgery or in surgical procedures during which contact with cerebrospinal fluid or dura mater may occur.14In a phase III, randomized, single-blind, parallel-group, multicenter study,15 the fibrin sealant CROSSEAL™ (Ethicon, Inc., Somerville, NJ) significantly reduced the time to hemostasis during liver resection surgery compared with conventional hemostatic techniques. EVICEL® Fibrin Sealant (Human) (Ethicon, Inc.), the successor of CROSSEAL, requires no antifibrinolytic additive and is therefore both aprotinin and tranexamic acid free, and achieves hemostasis using exclusively human components.16 The effectiveness and safety of this fibrin sealant for hemostasis in soft tissue during elective retroperitoneal or intra-abdominal surgery were compared with an absorbable hemostat (SURGICEL® Absorbable Hemostat; Ethicon, Inc.) in a randomized, active-controlled, multicenter study.17 This article describes a subanalysis of data from the largest patient subgroup from that study, and evaluates the effectiveness and safety of a fibrin sealant versus an absorbable hemostat for patients who underwent urologic surgical procedures.  相似文献   
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Background

Herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) are common human pathogens and might cause severe illness. Following primary infection, the viruses establish lifelong latent infection and are transmitted by close contact, both sexual and nonsexual. However, the information about the seroprevalence of HSV-1 and HSV-2 across all age groups is limited.

Methods

Residual sera collected during the nationwide serosurvey in 2007 in Taiwan were selected for the study. The enzyme-linked immunosorbent assay was used to detect anti-HSV-1 and anti-HSV-2 type-specific glycoprotein IgG. Demographics and personal health data were used for risk analysis.

Results

A total of 1411 and 1072 serum samples were included for anti-HSV-1 and anti-HSV-2 seroprevalence analysis, respectively. The weighted overall seroprevalence was 63.2% for HSV-1, and 7.7% for HSV-2, respectively. The HSV-1 seropositive rate was 19.2% for those less than 5 years old, increased to 46.4% for those aged 5–13 years, 60.9% for those aged 14–29 years, and reached as much as 95.0% for those aged over 30 years. In contrast, the HSV-2 seropositve rate was 1.6% for those less than 30 years old, rose to 10.1% for those age 30–39 years, and was up to 31.2% for those aged over 60 years. A significantly higher HSV-2 seropositive rate was noted in females than males aged over 40 years (26.3% v.s. 16.8%), and the overall HSV-2 seropositive rate was almost twice higher in females than males. Smoking history, drinking habit, and educational level were associated with the HSV-1 seropositivity. Female gender and rural residence were independent factors for the HSV-2 seropositivity.

Conclusions

An obvious increase of primary HSV-1 infection occurred in late adolescents and young adults, joined by the rise of HSV-2 infection in middle-aged adults, especially females. The acquistion and transmission of HSV warrant further studies in the susceptible population.  相似文献   
8.

Background

Bipolar disorder types I (BD I) and II (BD II) behave differently in clinical manifestations, normal personality traits, responses to pharmacotherapies, biochemical backgrounds and neuroimaging activations. How the varied emotional states of BD I and II are related to the comorbid personality disorders remains to be settled.

Methods

We therefore administered the Plutchick – van Praag Depression Inventory (PVP), the Mood Disorder Questionnaire (MDQ), the Hypomanic Checklist-32 (HCL-32), and the Parker Personality Measure (PERM) in 37 patients with BD I, 34 BD II, and in 76 healthy volunteers.

Results

Compared to the healthy volunteers, patients with BD I and II scored higher on some PERM styles, PVP, MDQ and HCL-32 scales. In BD I, the PERM Borderline style predicted the PVP scale; and Antisocial predicted HCL-32. In BD II, Borderline, Dependant, Paranoid (-) and Schizoid (-) predicted PVP; Borderline predicted MDQ; Passive-Aggressive and Schizoid (-) predicted HCL-32. In controls, Borderline and Narcissistic (-) predicted PVP; Borderline and Dependant (-) predicted MDQ.

Conclusion

Besides confirming the different predictability of the 11 functioning styles of personality disorder to BD I and II, we found that the prediction was more common in BD II, which might underlie its higher risk of suicide and poorer treatment outcome.  相似文献   
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A susceptibility gene on chromosome 18 and a parent-of-origin effect have been suggested for bipolar affective disorder (BPAD). We have studied 28 nuclear families selected for apparent unilineal transmission of the BPAD phenotype, by using 31 polymorphic markers spanning chromosome 18. Evidence for linkage was tested with affected-sib-pair and LOD score methods under two definitions of the affected phenotype. The affected-sib-pair analyses indicated excess allele sharing for markers on 18p within the region reported previously. The greatest sharing was at D18S37: 64% in bipolar and recurrent unipolar (RUP) sib pairs (P = .0006). In addition, excess sharing of the paternally, but not maternally, transmitted alleles was observed at three markers on 18q: at D18S41, 51 bipolar and RUP sib pairs were concordant for paternally transmitted alleles, and 21 pairs were discordant (P = .0004). The evidence for linkage to loci on both 18p and 18q was strongest in the 11 paternal pedigrees, i.e., those in which the father or one of the father's sibs is affected. In these pedigrees, the greatest allele sharing (81%; P = .00002) and the highest LOD score (3.51; θ = 0.0) were observed at D18S41. Our results provide further support for linkage of BPAD to chromosome 18 and the first molecular evidence for a parent-of-origin effect operating in this disorder. The number of loci involved, and their precise location, require further study.  相似文献   
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The results of molecular genetic, biochemical and nuclear magnetic resonance studies on glutamine-binding protein of Escherichia coli suggest that the only two tryptophan residues, at positions 32 and 220, in the protein molecule are likely to be involved in (or sensitive to) interactions with the membrane-bound protein components of the glutamine transport system. It has been found that both tryptophan residues have limited motional freedom, are located away from the surface of the protein molecule and are not close to the ligand-binding site. Their presence, however, is required for the optimal transport of L-glutamine across the cytoplasmic membrane, though not essential for the ligand-binding process. The relevance of these results to the structure and function of the glutamine-binding protein in the glutamine transport system is discussed.  相似文献   
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