The Nobel Prize in Physiology or Medicine 2019 – Sensing oxygen levels
The AC133 antigen is a novel antigen selectively expressed on a subset of CD34+ cells in human fetal liver, bone marrow, and blood as demonstrated by flow cytometric analyses. In this study, we have further assessed the expression of AC133 on CD34+ cells in hemopoietic samples and found that there was a highly significant difference between normal bone marrow and cord blood versus aphereses (p <0.0001) but not between bone marrow and cord blood. Most of the clonogenic cells (67%) were contained in the CD34+AC133+ fraction. Compared with cultures of the CD34+AC133- cells, generation of progenitor cells in long-term culture on bone marrow stroma was consistently 10- to 100-fold higher in cultures initiated with CD34+AC133+ cells and was maintained for the 8-10 weeks of culture.
Clinical Trial – Hyperbaric Oxygen for Carbon Monoxide Induced Chronic Encephalopathy
in some patients, a few days or weeks after they recover from carbon monoxide poisoning they
develop new symptoms. These can affect mood, ability to think or remember clearly, and
movements. Some people develop movement problems that are similar to Parkinson’s disease.
This damage to brain tissue is called "encephalopathy," and this study will look at the
effect of pressurized oxygen therapy on long term, or chronic, encephalopathy.
Clinical Trial – Plethysmographic Variability Index in Post Spinal Anesthesia Hypotension in Cesarean Section
– Full term pregnant female patients presented for elective C.S for single viable fetus
will be included in this study.
– Before anesthesia, the patient will be attached to a monitor of: ECG , heart rate, non
invasive blood pressure, pulse taximeter applied on the index finger of the limb not
attached to the blood pressure cuff, pulse oximetry and plethysmographic variability
index (PVI) and perfusion index (PI) will be taken by (Massimo radical 7, Massimo corp.
USA). Measures will be recorded every 5 minutes preoperative.
– Patients with PVI <15 will be excluded from the study.
- Patients with PVI > 15 are started on intravenous infusion of warm ringer lactate
solution via suitable pore intravenous cannula to reach target of PVI <15 or a total 1
liter of ringer lactate.
- The patients in which the PVI is corrected by fluid to level below 15 will be Group (C)
or corrected group. Patients in which intravenous fluid administration did not result
any change in PVI or changed but still higher than 15 will be Group (NC) or non
corrected group.
After preoperative preparation patient is shifted to operating theater, with all monitors
applied. She will receive spinal block at lumbar 3-4 space with hyperbaric bupivacaine 8 mg
plus 25 mic fentanyl. After giving anesthesia and positioning for surgery with a left lateral
tilt of 15 degrees,
Clinical Trial – High-flow Oxygen for Vaso-occlusive Pain Crisis
Sickle cell disease (SCD) is characterized by recurrent vaso-occlusive pain crisis (VOC),
which may evolve to acute chest syndrome (ACS), the most common cause of death among adult
patients with SCD. Currently, there is no safe and effective treatment to abort VOC or
prevent secondary ACS. Management of VOC mostly involve a symptomatic approach including
hydration, analgesics, transfusion, and incentive spirometry, which was investigated in a
very limited number of patients (<30).
The polymerisation of HbS is one major feature in the pathogenesis of vaso-occlusion. Among
factors determining the rate and extent of HbS polymer formation, the hypoxic stimulus is one
of the most potent and readily alterable. Current guidelines recommend oxygen therapy in
patients with VOC in order to maintain a target oxygen saturation of 95%. Low-flow nasal
oxygen (LFNO) is routinely used to achieve this normoxia approach, particularly in patients
at risk of secondary ACS because they may experience acute desaturation. In contrast, various
case series suggest a potential beneficial role of intensified oxygen therapy targeting
hyperoxia for the management of VOC, particularly with the use of hyperbaric oxygen, but the
latter is difficult to implement in routine clinical practice.
A recent high-flow nasal oxygen (HFNO) technology allows the delivery of humidified gas at
high fraction of inspired oxygen (FiO2) through nasal cannula. The FiO2 can be adjusted up to
100% (allowing hyperoxia that may reverse sickling) and the flow can be increased up to 60
L/min (which generates positive airway pressure and dead space flushing, that may prevent
evolution of VOC towards ACS by alleviating atelectasis and opioid-induced hypercapnia). In
patients with acute respiratory failure, HFNO has been shown to improve patient's comfort,
oxygenation, and survival as compared to standard oxygen or non-invasive ventilation.
The aim of the present study is to test the efficacy and safety of HFNO for the management of
VOC and prevention of secondary ACS. The investigators will use a multi-arm multi-stage
(MAMS) design to achieve these goals. HFNO will be delivered through AIRVO 2 (Fisher and
Paykel Healthcare, New Zealand), a device that incorporates a turbine allowing its use in
hospital wards.