Palladin Expression in Primary Cultures of Pancreatic Ductal Cells Derived from Increasingly Neoplastic Samples. Expression of Palladin RNA increases relative to the degree of precancer to cancer: normal to PanIN 1 (hyperplasia) to PanIN 3 (carcinoma in situ) to cancer. Each bar represents epithelial cell cultures from one person. The PanIN 1 and PanIN 3 lesions (lower left photomicrograph) were purified from two affected members of Family X. The pancreatic cancer epithelial cells (lower right photomicrograph) were purified from a sample of sporadic adenocarcinoma.
White matter is one of the two components of the central nervous system and consists mostly of glial cells and myelinated axons that transmit signals from one region of the cerebrum to another and between the cerebrum and lower brain centers. White matter tissue of the freshly cut brain appears pinkish white to the naked eye because myelin is composed largely of lipid tissue veined with capillaries. Its white color is due to its usual preservation in formaldehyde.
White matter is composed of bundles of myelinated nerve cell processes (or axons), which connect various grey matter areas (the locations of nerve cell bodies) of the brain to each other, and carry nerve impulses between neurons. Myelin acts as an insulator, increasing the speed of transmission of all nerve signals.
Image: White matter structure of human brain (taken by MRI).
In the past few years, next-generation cancer drugs have started trickling into the clinics, including a smart inhibitor that block a specific mutant kinase (V600E-B-RAF) and antibodies that can induce T cell-mediated rejection of certain tumors (anti-CTL4 antibodies). Another promising approach is to genetically modify T cells to attack tumors and then infuse the cells into cancer patients. Indeed, this strategy is currently entering clinical trials, specifically with T cells engineered to express the chimeric antigen receptors (CARs).
Movie: Here T cells (gray) are engineered to express chimeric antigen receptors (CARs) to redirect T-cell specificity to target CD19-positive tumor cells, expressing EGFP (green). Tumor cells turn red after the T-cell attacks and kills them (propidium iodide staining). The time-lapse imaging was performed using Nikon’s BioStation. Video presented by Alex’s Lemonade Stand Foundation.
All bleeding eventually stops.
ATP production in mitochondria (purple) can lead to the formation of reactive oxygen species (ROS) that damage mitochondria. When an organelle is beyond repair, the cellular recycling system (green) kicks-in and targets them for mitophagy, a specialized form of mitochondrial degradation.
Image: A primary retinal ganglion cell expresses a red fluorescent protein targeted to mitochondria, a green fluorescent protein fused to the autophagosomal marker LC3, and a cyan fluorescent protein in the cytosol. This image reveals how autophagosomes (green) can contact individual mitochondria (purple), before their ingestion by mitophagy.
It is currently difficult for physicians to detect small tumors and the precise boundaries of tumors during surgery. Fluorescent probes have improved tumor visualization, but these probes typically have high background signal or requires hours to illuminate. Recently, Kobayashi and colleagues developed a fluorescence probe- γ-glutamyl hydroxymethyl rhodamine green- that rapidly turns fluorescent green when it interacts with cancer cells, but not normal tissue (specifically when γ-glutamyltranspeptidase on the surface of cancer cells cleaves glutamate off the probe). When the probe is sprayed onto an in vivo mouse model of ovarian cancer, the probe activates within 1 minute, illuminating tumors <1 mm in diameter.
Movie: The hydroxymethyl rhodamine green probe is sprayed on a peritoneally disseminated SHIN3 ovarian cancer in a mouse. The movie was obtained with a regular camcorder.
The Neural Tube
- the neural tube forms the brain and spinal cord
- fusion of neural groove extends rostrally and caudally
- begins at the level of 4th somite
- closes neural groove “zips up” in some species.
- humans appear to close at multiple points along the tube.
- leaves 2 openings at either end - Neuropores
- cranial neuropore closes before caudal
Failure for the neural tube to close correctly or completely results in a neural tube defect.
Pterional Craniotomy from the Columbia Neurosurgery Online Curriculum