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Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:06.54,0:00:09.45,Default,,0000,0000,0000,,While regaling you with daring \Nstories from her youth,
Dialogue: 0,0:00:09.45,0:00:13.36,Default,,0000,0000,0000,,it might be hard to believe your \Ngrandmother used to be a trapeze artist.
Dialogue: 0,0:00:13.36,0:00:18.34,Default,,0000,0000,0000,,However, the bad backs, elbow pain, \Nand creaky knees so common in older people
Dialogue: 0,0:00:18.34,0:00:20.50,Default,,0000,0000,0000,,is more than just “old age."
Dialogue: 0,0:00:20.50,0:00:25.16,Default,,0000,0000,0000,,In fact, the source of this stiffness \Nplagues many young people as well.
Dialogue: 0,0:00:25.16,0:00:26.84,Default,,0000,0000,0000,,The culprit is arthritis:
Dialogue: 0,0:00:26.84,0:00:29.97,Default,,0000,0000,0000,,a condition that causes inflammation \Nand pain in the joints
Dialogue: 0,0:00:29.97,0:00:33.69,Default,,0000,0000,0000,,of over 90 million people \Nin the U.S. alone.
Dialogue: 0,0:00:33.69,0:00:36.57,Default,,0000,0000,0000,,But are stiff, creaky joints \Nreally inevitable?
Dialogue: 0,0:00:36.57,0:00:38.78,Default,,0000,0000,0000,,What makes arthritis so pervasive,
Dialogue: 0,0:00:38.78,0:00:42.62,Default,,0000,0000,0000,,and why haven’t we found a cure for \Nthis widespread condition?
Dialogue: 0,0:00:42.62,0:00:45.54,Default,,0000,0000,0000,,The first hurdle is that arthritis \Nis actually a spectrum
Dialogue: 0,0:00:45.54,0:00:48.95,Default,,0000,0000,0000,,of over 100 different arthritic \Nconditions.
Dialogue: 0,0:00:48.95,0:00:53.10,Default,,0000,0000,0000,,All these conditions share symptoms \Nof joint pain and inflammation,
Dialogue: 0,0:00:53.10,0:00:57.12,Default,,0000,0000,0000,,but the origin and severity of those \Nsymptoms vary widely.
Dialogue: 0,0:00:57.12,0:00:59.81,Default,,0000,0000,0000,,Even the most common type, \Nosteoarthritis,
Dialogue: 0,0:00:59.81,0:01:02.22,Default,,0000,0000,0000,,is trickier to prevent than \None might think.
Dialogue: 0,0:01:02.22,0:01:06.24,Default,,0000,0000,0000,,It’s a general misconception that \Narthritis is confined to old age.
Dialogue: 0,0:01:06.24,0:01:10.64,Default,,0000,0000,0000,,The origins of osteoarthritis can often \Nbe traced to a patient’s early life,
Dialogue: 0,0:01:10.64,0:01:13.68,Default,,0000,0000,0000,,from any seemingly ordinary joint injury.
Dialogue: 0,0:01:13.68,0:01:18.21,Default,,0000,0000,0000,,Following impact, immune cells rush in \Nto help clean and repair the damaged site
Dialogue: 0,0:01:18.21,0:01:20.00,Default,,0000,0000,0000,,and begin pumping out enzymes,
Dialogue: 0,0:01:20.00,0:01:24.06,Default,,0000,0000,0000,,including matrix metalloproteinases \Nand aggrecanases.
Dialogue: 0,0:01:24.06,0:01:28.22,Default,,0000,0000,0000,,These enzymes clear out the damaged \Ntissue and contribute to inflammation.
Dialogue: 0,0:01:28.22,0:01:31.54,Default,,0000,0000,0000,,But while this rapid swelling helps \Nprotect the joint during recovery,
Dialogue: 0,0:01:31.54,0:01:36.22,Default,,0000,0000,0000,,inadequately healed tissue can cause these\Nimmune cells to overstay their welcome.
Dialogue: 0,0:01:36.22,0:01:39.74,Default,,0000,0000,0000,,The continuing flood of enzymes starts \Nto degrade the cartilage,
Dialogue: 0,0:01:39.74,0:01:43.13,Default,,0000,0000,0000,,weakening the joint and leading \Nto arthritis later on.
Dialogue: 0,0:01:43.13,0:01:47.81,Default,,0000,0000,0000,,Not all forms of arthritis can simply \Nbe traced to an old sports injury.
Dialogue: 0,0:01:47.81,0:01:52.58,Default,,0000,0000,0000,,Take rheumatoid arthritis, which \Naffects 1.3 million U.S. adults.
Dialogue: 0,0:01:52.58,0:01:55.25,Default,,0000,0000,0000,,This condition is actually an \Nautoimmune disease
Dialogue: 0,0:01:55.25,0:01:58.86,Default,,0000,0000,0000,,in which autoantibodies target \Nnatively produced proteins,
Dialogue: 0,0:01:58.86,0:02:01.87,Default,,0000,0000,0000,,some of which are secreted \Nby cartilage cells.
Dialogue: 0,0:02:01.87,0:02:04.11,Default,,0000,0000,0000,,We still don’t know what \Ncauses this behavior,
Dialogue: 0,0:02:04.11,0:02:08.20,Default,,0000,0000,0000,,but the result is that the body treats \Njoint tissue like a foreign invader.
Dialogue: 0,0:02:08.20,0:02:13.24,Default,,0000,0000,0000,,Immune cells infiltrate the joint despite \Nthere being no tissue damage to repair.
Dialogue: 0,0:02:13.24,0:02:15.98,Default,,0000,0000,0000,,This response leads to chronic \Ninflammation,
Dialogue: 0,0:02:15.98,0:02:18.89,Default,,0000,0000,0000,,which destroys bone and cartilage.
Dialogue: 0,0:02:18.89,0:02:21.65,Default,,0000,0000,0000,,Yet another condition, \Nspondyloarthritis,
Dialogue: 0,0:02:21.65,0:02:24.71,Default,,0000,0000,0000,,has similarities to both of the \Nconditions we’ve covered.
Dialogue: 0,0:02:24.71,0:02:27.77,Default,,0000,0000,0000,,Patients experience continuous \Ninflammation in the joints
Dialogue: 0,0:02:27.77,0:02:30.91,Default,,0000,0000,0000,,and at the sites where ligaments and \Ntendons attach to bones,
Dialogue: 0,0:02:30.91,0:02:33.26,Default,,0000,0000,0000,,even without any initial injury.
Dialogue: 0,0:02:33.26,0:02:37.84,Default,,0000,0000,0000,,This leads to the flood of enzymes and \Ndegradation seen in osteoarthritis,
Dialogue: 0,0:02:37.84,0:02:42.03,Default,,0000,0000,0000,,but is driven by different inflammatory \Nproteins called cytokines.
Dialogue: 0,0:02:42.03,0:02:44.36,Default,,0000,0000,0000,,As the enzymes eat away at cartilage,
Dialogue: 0,0:02:44.36,0:02:48.41,Default,,0000,0000,0000,,the body attempts to stabilize smaller \Njoints by fusing them together.
Dialogue: 0,0:02:48.41,0:02:52.55,Default,,0000,0000,0000,,This process sometimes leads to \Noutgrowths called bone spurs,
Dialogue: 0,0:02:52.55,0:02:56.02,Default,,0000,0000,0000,,which also cause intense stiffness \Nand joint pain.
Dialogue: 0,0:02:56.02,0:02:58.30,Default,,0000,0000,0000,,With so many factors causing arthritis,
Dialogue: 0,0:02:58.30,0:03:01.40,Default,,0000,0000,0000,,our current treatments are tailored \Nto tackle specific symptoms
Dialogue: 0,0:03:01.40,0:03:03.40,Default,,0000,0000,0000,,rather than underlying causes.
Dialogue: 0,0:03:03.40,0:03:05.84,Default,,0000,0000,0000,,These range from promising \NMACI techniques,
Dialogue: 0,0:03:05.84,0:03:09.93,Default,,0000,0000,0000,,which harvest cells from small pieces \Nof cartilage to grow replacement tissue.
Dialogue: 0,0:03:09.93,0:03:12.27,Default,,0000,0000,0000,,To a technique called microfracture,
Dialogue: 0,0:03:12.27,0:03:14.77,Default,,0000,0000,0000,,where surgeons create small \Nholes in the bone,
Dialogue: 0,0:03:14.77,0:03:19.18,Default,,0000,0000,0000,,allowing bone marrow stem cells to \Nleak out and form new cartilage.
Dialogue: 0,0:03:19.18,0:03:20.33,Default,,0000,0000,0000,,As a last resort,
Dialogue: 0,0:03:20.33,0:03:24.83,Default,,0000,0000,0000,,people with withered cartilage can \Neven undergo full joint replacements.
Dialogue: 0,0:03:24.83,0:03:26.66,Default,,0000,0000,0000,,But outside these drastic measures,
Dialogue: 0,0:03:26.66,0:03:29.42,Default,,0000,0000,0000,,the underlying drivers of \Nautoimmune arthritis
Dialogue: 0,0:03:29.42,0:03:32.44,Default,,0000,0000,0000,,still present a unique \Ntreatment challenge.
Dialogue: 0,0:03:32.44,0:03:36.83,Default,,0000,0000,0000,,Scientists are making progress with \Ntherapies that block TNF-alpha,
Dialogue: 0,0:03:36.83,0:03:40.85,Default,,0000,0000,0000,,one of the primary proteins causing \Ninflammation in rheumatoid arthritis.
Dialogue: 0,0:03:40.85,0:03:46.02,Default,,0000,0000,0000,,But even this approach only treats the \Nsymptoms of the condition, not the cause.
Dialogue: 0,0:03:46.02,0:03:51.51,Default,,0000,0000,0000,,In the meantime, some of our best defenses\Nagainst arthritis are lifestyle choices:
Dialogue: 0,0:03:51.51,0:03:54.54,Default,,0000,0000,0000,,maintaining a healthy weight to \Ntake pressure off joints,
Dialogue: 0,0:03:54.54,0:03:59.26,Default,,0000,0000,0000,,low-impact exercises like yoga or cycling,\Nand avoiding smoking.
Dialogue: 0,0:03:59.26,0:04:03.19,Default,,0000,0000,0000,,These arthritis-fighting behaviors \Ncan help us lead longer lives
Dialogue: 0,0:04:03.19,0:04:06.09,Default,,0000,0000,0000,,as we continue to research \Ncures and treatments
Dialogue: 0,0:04:06.09,0:04:09.10,Default,,0000,0000,0000,,for the huge diversity of \Narthritic conditions.