Exponential Spread of Hepatitis C Virus Genotype 4a in Egypt

Hepatitis C virus (HCV) infects >10% of the general population in Egypt, in which intravenous injection with an antimony compound for endemic schistosomiasis in the past has been implicated. To simulate the epidemic history of HCV in Egypt, sera were obtained from 3608 blood donors at 13 governorates in or surrounding the Nile valley during 1999. The prevalence of antibody to HCV (anti-HCV) and genotypes was determined in them, and the molecular evolutionary analysis based on the neutral theory was applied to HCV isolates of genotype 4a, which is outstandingly prevalent in Egypt and indigenous there. Of 3608 sera, 317 (8.8%) were positive for anti-HCV. The molecular evolutionary analysis on 47 HCV genotype 4a isolates of carriers from various districts in Egypt indicated that the spread of HCV-4a would have increased exponentially during the 1940s through 1980 when oral medications became available. In conclusion, the estimated spread time is consistent with the duration of intravenous antimony campaigns in Egypt.     

Acrosome reaction in spermatozoa from the amphioxus Branchiostoma belcheri (Cephalochordata, Chordata)

The formation of an acrosomal process at acrosomal exocytosis in spermatozoa of the amphioxus was described in the present report for the first time. A non-reacted acrosome was located in front of the nucleus, where a cup-shaped acrosomal vesicle covered a conical accumulation of subacrosomal material. When naturally spawned spermatozoa were treated with a calcium ionophore, ionomycin, the acrosomal vesicle opened at the apex and an acrosomal process was projected. The process exhibited a filamentous structure. The reaction followed the mode typically seen in marine invertebrates. These observations suggest that the features and function of the acrosome of amphioxus, whose position is on the border between invertebrates and vertebrates, reflect their ecological adaptation and phylogenic position.     

Knockdown of the mitochondria‐localized protein p13 protects against experimental parkinsonism

Mitochondrial dysfunction in the nigrostriatal dopaminergic system is a critical hallmark of Parkinson's disease (PD). Mitochondrial toxins produce cellular and behavioural dysfunctions resembling those in patients with PD. Causative gene products for familial PD play important roles in mitochondrial function. Therefore, targeting proteins that regulate mitochondrial integrity could provide convincing strategies for PD therapeutics. We have recently identified a novel 13‐kDa protein (p13) that may be involved in mitochondrial oxidative phosphorylation. In the current study, we examine the mitochondrial function of p13 and its involvement in PD pathogenesis using mitochondrial toxin‐induced PD models. We show that p13 overexpression induces mitochondrial dysfunction and apoptosis. p13 knockdown attenuates toxin‐induced mitochondrial dysfunction and apoptosis in dopaminergic SH‐SY5Y cells via the regulation of complex I. Importantly, we generate p13‐deficient mice using the CRISPR/Cas9 system and observe that heterozygous p13 knockout prevents toxin‐induced motor deficits and the loss of dopaminergic neurons in the substantia nigra. Taken together, our results suggest that manipulating p13 expression may be a promising avenue for therapeutic intervention in PD.     

Occurrence of unusual tubular invaginations of the plasma membrane in smooth muscle cells of the lamprey,Lampetra japonica

Numerous tubular structures were observed in the surface region of smooth muscle cells making up the vascular walls in the lamprey, Lampetra japonica; they were designated as surface tubules. The limiting membrane of the surface tubules was connected to the plasma membrane, allowing communication of the lumen of the tubule with the extracellular space. Tannic acid reacted with osmium, serving as an extracellular marker, penetrated into the tubules but not into the intracellular organelles, such as the endoplasmic reticulum and the Golgi complex. The surface tubules were grouped in longitudinal parallel rows, separated from each other by tubule-free areas where dense plaques were present. Each tubule was fairly cylindrical (approximately 60 nm in diameter) and often ramified into two or three branches with a blind end. Occasionally, these tubules were encircled by the sarcoplasmic reticulum which was located immediately beneath the plasma membrane. Similar tubules were also observed in the surface region of vascular endothelial cells and fibroblasts in the adventitial connective tissue. The possibility that the surface tubules in the present observations are analogous to the smooth muscle caveolae or the striated muscle T-tubule is discussed.     

Two phenological variants of Terminalia alata coexist in a dry dipterocarp forest

Two morphological variants of Terminalia alata (Combretaceae) differed in leaf flushing phenology and spatial distribution in a Cambodian deciduous forest. The hairy‐type trees displayed leaf exchange behavior in the middle of the dry season. The glabrous type flushed new leaves 3 months after the wet season started. The leafless period of the hairy type was estimated to be <1 month, whereas that of the glabrous type lasted more than 5 months. The landscape‐scale leaf exchange behavior was similar to that of the hairy type. The two types showed clear spatial separation. The hairy type was limited to flat areas with deep soils. The dominance of the glabrous type in hilly areas with shallow soils suggests that it is adapted to water‐limited environments. The abundance of the glabrous type in hilly areas and its unique leaf phenology probably influence the carbon, energy and water balance at the landscape level.     

Intercellular communications within the rat anterior pituitary. XVI: Postnatal changes of distribution of S-100 protein positive cells,connexin 43 and LH-RH positive sites in the pars tuberalis of the rat pituitary gland. An immunohistochemical and electron microscopic study

The architecture of luteinizing hormone-releasing hormone (LH-RH) nerve ends and the S-100 protein containing folliculo-stellate cells forming gap junctions in the pars tuberalis is basically important in understanding the regulation of the hormone producing mechanism of anterior pituitary glands. In this study, intact male rats 5–60 days old were prepared for immunohistochemistry and electron microscopy. From immunostained sections, the S-100 containing cells in pars tuberalis were first detected on day 30 and increased in number to day 60; this was parallel to the immunohistochemical staining of gap junction protein, connexin 43. LH-RH positive sites were clearly observed on just behind the optic chiasm and on the root of pituitary stalk on day 30. On day 60, the width of layer increased, while follicles and gap junctions were frequently observed between agranular cells in 10 or more layers of pars tuberalis.     

Ca/calmodulin-dependent protein kinase phosphatase (CaMKP) is indispensable for normal embryogenesis in zebrafish, Danio rerio

Ca²⁺/calmodulin-dependent protein kinase phosphatase (CaMKP) dephosphorylates and regulates multifunctional Ca²⁺/calmodulin-dependent protein kinases (CaMKs). However, the biological functions of this enzyme have not been clarified in vivo. To investigate the biological significance of CaMKP during zebrafish embryogenesis, we cloned and characterized zebrafish CaMKP (zCaMKP). The isolated cDNA clone possessed an open reading frame of 1272 bp encoding 424 amino acids and shared 47% and 48% amino acid identity with rat and human CaMKP, respectively. Interestingly, zCaMKP lacks the Glu cluster corresponding to residues 101-109 in the rat enzyme, and was not activated by polycations such as poly-l-lysine. The recombinant zCaMKP required Mg²⁺ rather than Mn²⁺ for activity. Furthermore, zCaMKP dephosphorylated CaMKIV but not phosphorylase a, α-casein, or extracellular signal-regulating kinase (ERK), suggesting that the enzyme regulates Ca²⁺ signaling pathways in zebrafish. Cotransfection of zCaMKP with mammalian CaMKI significantly decreased phospho-CaMKI in ionomycin-stimulated 293T cells. During embryogenesis, the expression of zCaMKP increased gradually after 48 h post-fertilization, as demonstrated by Western blotting using an anti-zCaMKP antibody. The knockdown of the zCaMKP gene with morpholino-based antisense oligonucleotides resulted in an increased incidence of embryos with severe morphological and cellular abnormalities, i.e., a significant increase in the number of round-shaped embryos and apoptotic cells in the whole body. A marked decrease in zCaMKP expression was observed in the antisense- but not control oligo-injected embryos. Embryonic death was rescued by coinjection with recombinant rat CaMKP but not with phosphatase-dead mutant (D194A). These results clearly show the significance of zCaMKP during zebrafish embryogenesis.     

Radio frequency magnetic field effects on molecular dynamics and iron uptake in cage proteins

The protein ferritin has a natural ferrihydrite nanoparticle that is superparamagnetic at room temperature. For native horse spleen ferritin, we measure the low field magnetic susceptibility of the nanoparticle as 2.2 × 10^?6 m³ kg^?1 and its Néel relaxation time at about 10^?10 s. Superparamagnetic nanoparticles increase their internal energy when exposed to radio frequency magnetic fields due to the lag between magnetization and applied field. The energy is dissipated to the surrounding peptidic cage, altering the molecular dynamics and functioning of the protein. This leads to an increased population of low energy vibrational states under a magnetic field of 30 µT at 1 MHz, as measured via Raman spectroscopy. After 2 h of exposure, the proteins have a reduced iron intake rate of about 20%. Our results open a new path for the study of non‐thermal bioeffects of radio frequency magnetic fields at the molecular scale. Bioelectromagnetics 31:311–317, 2010. © 2010 Wiley‐Liss, Inc.     

AMP-activated protein kinase positively regulates FGF-2-stimulated VEGF synthesis in osteoblasts

AMP-activated protein kinase (AMPK) is recognized as a regulator of energy homeostasis. We have previously reported that basic fibroblast growth factor (FGF-2) stimulates vascular endothelial growth factor (VEGF) release through the activation of p44/p42 mitogen-activated protein (MAP) kinase and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) in osteoblast-like MC3T3-E1 cells. In the present study, we investigated the involvement of AMPK in FGF-2-stimulated VEGF release in these cells. FGF-2 time-dependently induced the phosphorylation of AMPK α-subunit (Thr-172). Compound C, an AMPK inhibitor, which suppressed the FGF-2-induced phosphorylation of AMPK, significantly inhibited the VEGF release stimulated by FGF-2. The AMPK inhibitor also reduced the mRNA expression of VEGF induced by FGF-2. The FGF-2-induced phosphorylation of both p44/p42 MAP kinase and SAPK/JNK was attenuated by compound C. These results strongly suggest that AMPK positively regulates the FGF-2-stimulated VEGF synthesis via p44/p42 MAP kinase and SAPK/JNK in osteoblasts.