Effect of Central Antileptin Antibody on the Onset of Female Rat Puberty

The effect of intracerebroventricular (ICV) antileptin antibody on the onset of puberty in the female rat and the relationship between serum leptin, luteinizing hormone (LH), and body weight were investigated. Antileptin antibody (group A) was infused ICV from days 23–36 in prepubertal female rats whereas the control (group B) received ICV goat immunoglobulin G (IgG). In the antileptin group, mean day of vaginal opening (VO) was postponed (day 34 versus day 30, P < .01 ). Body weight trended higher after 30 days in the antileptin group but not significantly. However, there was no difference in serum leptin and LH between the two groups on the day of VO. Serum leptin was relatively constant from day 23 through day 31 and did not correlate with LH (r = 0.14, P = .10). These studies demonstrate that central leptin promotes the onset of female rat puberty as evidenced by VO. Finally, central leptin impacts female rat pubertal onset in distinction from serum leptin and body weight

Local and Nonlocal Optically Induced Transparency Effects in Graphene–Silicon Hybrid Nanophotonic Integrated Circuits

Graphene is well-known as a two-dimensional sheet of carbon atoms arrayed in a honeycomb structure. It has some unique and fascinating properties, which are useful for realizing many optoelectronic devices and applications, including transistors, photodetectors, solar cells, and modulators. To enhance light–graphene interactions and take advantage of its properties, a promising approach is to combine a graphene sheet with optical waveguides, such as silicon nanophotonic wires considered in this paper. Here we report <i>local</i> and <i>nonlocal</i> optically induced transparency (OIT) effects in graphene–silicon hybrid nanophotonic integrated circuits. A low-power, continuous-wave laser is used as the pump light, and the power required for producing the OIT effect is as low as ∼0.1 mW. The corresponding power density is several orders lower than that needed for the previously reported saturated absorption effect in graphene, which implies a mechanism involving light absorption by the silicon and photocarrier transport through the silicon–graphene junction. The present OIT effect enables low power, all-optical, broadband control and sensing, modulation and switching <i>locally</i> and <i>nonlocally</i>

Syntaxin-11 is expressed in primary human monocytes/macrophages and acts as a negative regulator of macrophage engulfment of apoptotic cells and IgG-opsonized target cells

Syntaxin-11 is a member of a family of membrane-trafficking proteins referred to as soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). Recent studies have shown that syntaxin-11 is expressed in natural killer cells and cytotoxic T cells and is likely to play a role in the granule exocytosis pathway. However, the biological role of syntaxin-11 in other immune cells has remained elusive. This study found that stimulation with interferon-gamma upregulated syntaxin-11 expression in primary monocytes. Experiments using monocytes from patients with familial haemophagocytic lymphohistiocytosis harbouring mutations in the gene encoding syntaxin-11 (STX11), or monocytes from healthy individuals in which syntaxin-11 was downregulated using specific short-interfering RNA, demonstrated that syntaxin-11 was not required for antibody-dependent cellular cytotoxicity. On the other hand, silencing of syntaxin-11 expression in primary macrophages enhanced the phagocytosis of apoptotic target cells with a concomitant increase in macrophage secretion of tumour necrosis factor-alpha. Moreover, Fc gamma-receptor-mediated uptake of target cells was also enhanced following silencing of syntaxin-11 expression in macrophages. In addition, syntaxin-11 localized to the plasma membrane in macrophages ingesting apoptotic cell corpses. Syntaxin-11 thus appears to act as a negative regulator of human macrophage engulfment of apoptotic cells and IgG-opsonized red blood cells

A sandwich-type DNA electrochemical biosensor for hairpin-stem-loop structure based on multistep temperature-controlling method

National High Technology and Development of China (863 Project) [2012AA022604]; National Natural Science Foundation of China [20975021, 21175023, 81171668, 21275028]; Fujian Provincial University-Industry Cooperation Science and Technology Major Program [2010Y4003]; Foundation of Fujian Key Laboratory of Hematology [2009J1004]; Scientific Research Major Program of Fujian Medical University [09ZD013]; Natural Science Foundation of Fujian Province of China [2010J06011, 2012J01428]; Medical innovation subject of Fujian Province of China [2012-CX-30]; Science and Technology Project of Fuzhou City of China [2011-S-67-3]A highly sensitive and selective method for amplified electrochemical detection for hairpin-stem-loop structured target sequences was developed based on the temperature regulation of DNA hybrids on a sandwich-type electrochemical DNA sensor. Multistep hybridization was applied to promote the hybridization efficiency of each section of sandwich structure. The results showed that both multistep and temperature-controlling hybridization techniques were both especially made to fabricate the sensor for the tendency of internal hybridization of target gene sequences. This strategy provides significantly enhanced hybridization efficiency and sequence specificity of electrochemical detection

Defective cytotoxic lymphocyte degranulation in syntaxin-11-deficient familial hemophagocytic lymphohistiocytosis 4 (FHL4) patients

Familial hemophagocytic lymphohistiocytosis (FHL) is typically an early onset, fatal disease characterized by a sepsislike illness with cytopenia, hepatosplenomegaly, and deficient lymphocyte cytotoxicity. Disease-causing mutations have been identified in genes encoding perforin (PRF1/FHL2), Munc13-4 (UNC13D/FHL3), and syntaxin-11 (STX11/FHL4). In contrast to mutations leading to loss of perforin and Munc13-4 function, it is unclear how syntaxin-11 loss-of-function mutations contribute to disease. We shove here that freshly isolated, resting natural killer (NK) cells and CD8(+) T cells express syntaxin-11. In infants, NK cells are the predominant perforin-containing cell type. NK cells from FHL4 patients fail to degranulate when encountering susceptible target cells. Unexpectedly, IL-2 stimulation partially restores degranulation and cytotoxicity by NK cells, which could explain the less severe disease progression observed in FHL4 patients, compared with FHL2 and FHL3 patients. Since the effector T-cell compartment is still immature in infants, our data suggest that the observed defect in NK-cell degranulation may contribute to the pathophysiology of FHL, that evaluation of NK-cell degranulation in suspected FHL patients may facilitate diagnosis, and that these new insights may offer novel therapeutic possibilities