Early human impacts and ecosystem reorganization in southern-central Africa.

Modern engage in substantial ecosystem modification, but it is difficult to detect the origins or early consequences of these behaviors. Archaeological, geochronological, geomorphological, and paleoenvironmental data from northern Malawi document a changing relationship between forager presence, ecosystem organization, and alluvial fan formation in the Late Pleistocene. Dense concentrations of Middle Stone Age artifacts and alluvial fan systems formed after ca.

PDGFR-β-Positive Perivascular Adventitial Cells Expressing Nestin Contribute to Fibrotic Scar Formation in the Striatum of 3-NP Intoxicated Rats.

Perivascular cells expressing platelet-derived growth factor receptor beta (PDGFR-β) have recently been implicated in fibrotic scar formation after acute brain injury, but their precise identity and detailed morphological characteristics remain elusive. This study sought to characterize and define the cellular phenotype of vascular-associated cells expressing PDGFR-β in the striatum of rats treated with the mitochondrial toxin 3-nitropropionic acid (3-NP). In the control striatum, PDGFR-β-positive cells were invariably localized on the abluminal side of smooth muscle cells of larger caliber vessels, and demonstrated morphological features typical of perivascular fibroblasts.

Morphological characterization of NG2 glia and their association with neuroglial cells in the 3-nitropropionic acid-lesioned striatum of rat.

Our aim was to examine the spatiotemporal profiles and phenotypic characteristics of neuron-glia antigen 2 (NG2) glia and their associations with neuroglial cells in striatal lesions due to the mitochondrial toxin 3-nitropropionic acid (3-NP). In control striatum, weak NG2 immunoreactivity was restricted to resting NG2 glia with thin processes, but prominent NG2 expression was noted on activated microglia/macrophages, and reactive NG2 glia in the lesion core after 3-NP injection. Activation of NG2 glia, including enhanced proliferation and morphological changes, had a close spatiotemporal relationship with infiltration of activated microglia into the lesion core.

Desmin expression profile in reactive astrocytes in the 3-nitropropionic acid-lesioned striatum of rat: Characterization and comparison with glial fibrillary acidic protein and nestin.

Desmin, a muscle-specific, type-III intermediate-filament protein, is reportedly expressed in astrocytes in the central nervous system. These cells become reactive astrocytes in response to brain injuries. To elucidate whether desmin is involved in this process, we examined the spatiotemporal expression profiles of desmin and their relationship with two astroglial intermediate filaments, glial fibrillary acidic protein (GFAP) and nestin, in the striatum of rats treated with the mitochondrial toxin 3-nitropropionic acid (3-NP).

Progressive accumulation of autofluorescent granules in macrophages in rat striatum after systemic 3-nitropropionic acid: a correlative light- and electron-microscopic study.

A variety of tissue biomolecules and intracellular structures are known to be autofluorescent. However, autofluorescent signals in brain tissues often confound analysis of the fluorescent markers used for immunohistochemistry. While investigating tissue and cellular pathologies induced by 3-nitropropionic acid, a mitochondrial toxin selective for striatal neurons, we encountered many autofluorescent signals confined to the lesion core.

Spatiotemporal expression of osteopontin in the striatum of rats subjected to the mitochondrial toxin 3-nitropropionic acid correlates with microcalcification.

Our aim was to elucidate whether osteopontin (OPN) is involved in the onset of mineralisation and progression of extracellular calcification in striatal lesions due to mitochondrial toxin 3-nitropropionic acid exposure. OPN expression had two different patterns when observed using light microscopy. It was either localised to the Golgi complex in brain macrophages or had a small granular pattern scattered in the affected striatum.

Increased Expression of Slit2 and its Robo Receptors During Astroglial Scar Formation After Transient Focal Cerebral Ischemia in Rats.

Slit2, a secreted glycoprotein, has recently been implicated in the post-ischemic astroglial reaction. The objective of this study was to investigate the temporal changes and cellular localization of Slit2 and its receptors, Robo1, Robo2, and Robo4, in a rat transient focal ischemia model induced by middle cerebral artery occlusion. We used double- and triple-immunolabeling to determine the cell-specific changes in Slit2 and its receptors during a 10-week post-ischemia period.

Increased expression of suppressor of cytokine signaling 2 in the subventricular zone after transient focal cerebral ischemia in adult rats.

Suppressor of cytokine signaling 2 (SOCS2) is a well-established negative regulator of growth hormone signaling that acts on adult hippocampal neurogenesis during ischemic insults. To explore whether SCOS2 is involved in poststroke neurogenesis, we studied the temporal expression of SOCS2 mRNA in the subventricular zone (SVZ) of rats after transient focal cerebral ischemia. We found that SOCS2 expression was upregulated in the SVZ of the infarcted hemisphere.

Enhanced expression of the calcium-sensing receptor in reactive astrocytes following ischemic injury in vivo and in vitro.

We recently demonstrated that the G protein-coupled calcium-sensing receptor (CaSR) is associated with the pathogenesis of ischemic stroke and may be involved in vascular remodeling and astrogliosis. To further substantiate the involvement of CaSR in the astroglial reaction common to ischemic insults, we investigated the temporal and cell type-specific expression patterns of CaSR in the hippocampus after transient forebrain ischemia. CaSR was constitutively expressed in neurons of the pyramidal and granule cell layers, whereas increased CaSR immunoreactivity was observed in reactive astrocytes, but not in activated microglia or macrophages, in the CA1 region of the post-ischemic hippocampus.

Absence of Benefit of Transcatheter Arterial Chemoembolization (TACE) in Patients with Resectable Solitary Hepatocellular Carcinoma.

Background: This study aimed to assess the prognostic impact of preoperative transcatheter arterial chemoembolization (TACE) on long-term survival outcomes in patients undergoing resection of small solitary hepatocellular carcinoma (HCC).

Methods: Enrolled patients had undergone macroscopic curative resection of solitary 2-5 cm HCC with (n = 105) or without (n = 830; control group) preoperative TACE.

Results: TACE group was divided into subgroups A (n = 68, 1-2 TACEs within 12 months), B (n = 23, ≥ 3 TACEs within 12 months), and C (n = 14, TACE prior to 12 months).

Prognostic effect of preoperative sequential transcatheter arterial chemoembolization and portal vein embolization for right hepatectomy in patients with solitary hepatocellular carcinoma.

Backgrounds/aims: Both preoperative transcatheter arterial chemoembolization (TACE) alone and portal vein embolization (PVE) alone have a detrimental prognostic effect on the post-resection outcomes in patients with hepatocellular carcinoma (HCC). The main objective of this study was to assess the prognostic impact of preoperative TACE on the long-term survival outcomes in patients undergoing preoperative PVE and right liver resection for solitary HCC.

Methods: Patients who underwent macroscopic curative right liver resection of solitary HCC that lied between 3.

A microfluidic magnetic bead impact generator for physical stimulation of osteoblast cell.

We developed a novel microfluidic cell culture device in which magnetic beads repetitively collide with osteoblast cells, MC3T3-E1, owing to attractive forces generated by pulsed electromagnetic fields and consequently the cells were physically stimulated by bead impacts. Our device consists of an on-chip microelectromagnet and a microfluidic channel which were fabricated by a microelectromechanical system technique. The impact forces and stresses acting on a cell were numerically analyzed and experimentally generated with different sizes of bead (4.