New approach in treating mental illness: Closed-loop enhancement and neural decoding of cognitive control in humans

 | Post date: 2021/11/26 | 
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Liver transplantation: history, outcomes and perspectives

 | Post date: 2021/11/22 | 

A liver transplant is a surgical procedure that removes a liver that no longer functions properly (liver failure) and replaces it with a healthy liver from a deceased donor or a portion of a healthy liver from a living donor. Liver transplant is usually reserved as a treatment option for people who have significant complications due to end-stage chronic liver disease. Liver transplant may also be a treatment option in rare cases of sudden failure of a previously healthy liver.
In 1963, Starzl et al. performed the first liver transplantation. In the first five liver transplantations no patient survived more than 23 days. In 1967, stimulated by Calne who used antilymphocytic serum, Starzl began a successful series of liver transplantation. Until 1977, 200 liver transplantations were performed in the world. In that period, technical problems were overcome. Roy Calne, in 1979, used the first time cyclosporine in two patients who had undergone liver transplantation. In 1989, Starzl et al. reported a series of 1,179 consecutives patients who underwent liver transplantation and reported a survival rate between one and five years of 73% and 64%, respectively.  Liver Transplantation Program was initiated at Hospital Israelita Albert Einstein in 1990 and so far according to the American Liver Foundation, around 8,000 liver transplant surgeries are performed in the United States every year.
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Bioactive scaffolds with enhanced supramolecular motion: promote recovery from spinal cord injury!

 | Post date: 2021/11/19 | 
The signaling of cells by scaffolds of synthetic molecules that mimic proteins is known to be effective in the regeneration of tissues. Álvarez et al. synthesized supramolecular peptide fibril scaffolds bearing two peptide sequences that promote nerve regeneration, one that reduces glial scarring and another that promotes blood vessel formation (see the Perspective by Wojciechowski and Stevens). In a mouse model of paralyzing human spinal cord injury, mutations in a tetrapeptide domain outside of the signaling regions improved recovery by promoting intense supramolecular motion within the fibrils. They describe peptide amphiphile supramolecular polymers containing two distinct signals and test them in a mouse model of severe spinal cord injury. One signal activates the transmembrane receptor β1-integrin and a second one activates the basic fibroblast growth factor 2 receptor. By mutating the peptide sequence of the amphiphilic monomers in nonbioactive domains, they intensified the motions of molecules within scaffold fibrils. This resulted in notable differences in vascular growth, axonal regeneration, myelination, survival of motor neurons, reduced gliosis, and functional recovery. 
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Diagnostic ultrasound: a valuable and safe procedure that uses low-power sound waves!

 | Post date: 2021/11/15 | 

The ultrasound image is produced based on the reflection of the waves off of the body structures. In an ultrasound exam, a transducer both sends the sound waves and records the echoing (returning) waves. When the transducer is pressed against the skin, it sends small pulses of inaudible, high-frequency sound waves into the body. As the sound waves bounce off internal organs, fluids and tissues, the sensitive receiver in the transducer records tiny changes in the sound's pitch and direction. A computer instantly measures these signature waves and displays them as real-time pictures on a monitor. The technologist typically captures one or more frames of the moving pictures as still images. They may also save short video loops of the images.
Ultrasound imaging is a medical tool that can help a physician evaluate, diagnose and treat medical conditions. Common ultrasound imaging procedures include:

  • Abdominal ultrasound (to visualize abdominal tissues and organs)
  • Bone sonometry (to assess bone fragility)
  • Breast ultrasound (to visualize breast tissue)
  • Doppler fetal heart rate monitors (to listen to the fetal heart beat)
  • Doppler ultrasound (to visualize blood flow through a blood vessel, organs, or other structures)
  • Echocardiogram (to view the heart)
  • Fetal ultrasound (to view the fetus in pregnancy)
  • Ultrasound-guided biopsies (to collect a sample of tissue)
  • Ophthalmic ultrasound (to visualize ocular structures
  • Ultrasound-guided needle placement (in blood vessels or other tissues of interest)

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Cord blood–derived mesenchymal stem cell: hope for recessive dystrophic epidermolysis bullosa patients!

 | Post date: 2021/11/11 | 
Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable disease that causes severe mucocutaneous fragility due to mutations in COL7A1 (encoding type VII collagen [C7]). the results of the first phase I/II clinical trial of intravenous administrations of allogeneic human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in patients with RDEB indicate that intravenous hUCB-MSC infusions were well tolerated, without serious adverse events. Improvements in the Birmingham Epidermolysis Bullosa Severity Score, body surface area involvement, blister counts, pain, pruritus, and quality of life were observed with maximal effects at 56–112 days after treatment. hUCB-MSC administration induced M2 macrophage polarization and reduced mast cell infiltration in RDEB skin. Serum levels of substance P were decreased after therapy.
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Neuro Embolization: a procedure used to treat an aneurysm!

 | Post date: 2021/11/9 | 
Embolization of brain aneurysms and arteriovenous malformations (AVM) uses imaging guidance to place small, soft metal coils into an aneurysm to block the flow of blood and prevent the aneurysm from rupturing. It also is used to fill AVMs – abnormal connections between arteries and veins – with liquid embolic agents (similar to fast-sealing glue). AVMs may prevent oxygenated blood from completely circulating throughout the brain and can cause a variety of problems, including headache, weakness, and other neurological symptoms. Embolization treats cerebral aneurysms and AVMs previously thought inoperable and is much less invasive than open surgery.
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Electroencephalography (EEG): the non-invasive brain imaging tools for assessing neurophysiological function!

 | Post date: 2021/11/5 | 
Electroencephalography (EEG) has been instrumental in making discoveries about cognition, brain function, and dysfunction. Hans Berger, a German psychiatrist, pioneered the EEG in humans in 1924. The EEG is an electrophysiological technique for the recording of electrical activity arising from the human brain.  EEG is particularly useful for evaluating patients with suspected seizures, epilepsy, and unusual spells. EEG uses the principle of differential amplification, or recording voltage differences between different points using a pair of electrodes that compares one active exploring electrode site with another neighboring or distant reference electrode.
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Hemodialysis: the most common type of dialysis!

 | Post date: 2021/11/2 | 

The renal functional capacity can be assessed by measuring serum creatinine/blood urea nitrogen (BUN) or by urea and creatinine clearance. There are two types of dialysis procedures; it may be hemodialysis (using a machine/artificial kidney-like apparatus) or peritoneal dialysis (using a peritoneal membrane as a filter). Peritoneal dialysis is recommended for younger patients because of its flexibility and can be performed at home. Hemodialysis is done for patients with no residual renal function. Dr. Willem Kolff is considered the father of dialysis. This young Dutch physician constructed the first dialyzer (artificial kidney) in 1943. 

The mechanism of hemodialysis:

In hemodialysis, the wastes and excess water are removed by using an external filter called a dialyzer, which contains a semipermeable membrane. The separation of wastes is done by creating a counter-current flow gradient, where blood flow is in one direction and the fluid of the dialyzer is in the opposite direction. Peritoneal dialysis uses the peritoneum as a natural semipermeable membrane and removes waste and water into the dialysate (the material or fluid that passes through the membrane of the dialysis).
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Gene therapy: providing hope for a way to restore visual function after ischemic injury!

 | Post date: 2021/10/28 | 
Neural circuits underlying brain functions are vulnerable to damage, including ischemic injury, leading to neuronal loss and gliosis. Neurons don't regenerate. The brain can sometimes remap its neural pathways enough to restore some visual function after a stroke, but that process is slow, it's inefficient, and for some patients, it never happens at all. A research team at Purdue University investigated the effect of NeuroD1-mediated in vivo direct reprogramming on visual cortical circuit integration and functional recovery in a mouse model of ischemic injury. After performing electrophysiological extracellular recordings and two-photon calcium imaging of reprogrammed cells in vivo and mapping the synaptic connections formed onto these cells ex vivo, they discovered that NeuroD1 reprogrammed neurons were integrated into the cortical microcircuit and acquired direct visual responses. Furthermore, following visual experience, the reprogrammed neurons demonstrated maturation of orientation selectivity and functional connectivity. their results show that NeuroD1-reprogrammed neurons can successfully develop and integrate into the visual cortical circuit leading to vision recovery after ischemic injury.
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Karyotyping: a crucial test for identifying genetic problems!

 | Post date: 2021/10/25 | 
A genetic screen can potentially diagnose more than 1,200 genetic disorders and chromosomal abnormalities. Karyotyping uses g-band analysis of metaphase chromosomal spreads, usually in 20 cells to identify chromosomal abnormalities such as trisomies, monosomies, translocations, and very large deletions and duplications. 

Karyotyping involves analysis of the entire chromosome complement through the microscope. Dividing cells are harvested during metaphase, the time of greatest chromosome condensation, by disruption of the spindle using drugs such as colchicine. Chromosomes are visualized by staining, including the use of special stains to elicit banding patterns. In general GC-rich regions tend to be gene rich and stain darkly with G-banding, bright with R-banding, and dark with Q-banding.

Karyotyping is able to detect polyploidy, aneuploidy, translocations, inversions, rings, and copy number changes in the size range of 4–6 Mb; smaller copy number changes require the use of molecular cytogenetic techniques.
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Pap smear: a screening procedure for cervical cancer!

 | Post date: 2021/10/21 | 
Cervical intraepithelial neoplasia (CIN) and cervical cancer are major health problems faced by women worldwide. The conventional Papanicolaou (Pap) smear analysis is an effective method to diagnose cervical pre-malignant and malignant conditions by analyzing swab images. Pap smear tests for the presence of precancerous or cancerous cells on your cervix. The cervix is the opening of the uterus. During the routine procedure, cells from your cervix are gently scraped away and examined for abnormal growth. It involves examining cells taken from the cervix under a microscope. The test doesn't diagnose cancer, but rather looks for abnormal cervical changes (cervical dysplasia)—precancerous or cancerous cells that could indicate cancer. If any are found, further testing, such as a colposcopy or biopsy, will be done in order to diagnose cancer. The test is named after George Papanicolaou, the Greek doctor who invented the procedure in the early 1940s.
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An alternative to using donated embryos resulting from IVF

 | Post date: 2021/10/15 | 
Researchers at the California Institute of Technology modeled human early embryo development with expanded pluripotent stem cells (EPSCs) in 3-dimensions!
They defined a protocol that allows them to generate self-organizing cystic structures from human EPSCs that display some hallmarks of human early embryogenesis. These structures mimic polarization and cavitation characteristic of pre-implantation development leading to blastocyst morphology formation and the transition to post-implantation-like organization upon extended culture. Single-cell RNA sequencing of these structures reveals subsets of cells bearing some resemblance to epiblast, hypoblast and trophectoderm lineages. Nevertheless, significant divergences from natural blastocysts persist in some key markers, and signalling pathways point towards ways in which morphology and transcriptional-level cell identities may diverge in stem cell models of the embryo. Thus, this stem cell platform provides insights into the design of stem cell models of embryogenesis.
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Impact of DaTscan Imaging on Clinical Decision in Parkinson’s Disease!

 | Post date: 2021/10/12 | 
In 2011, the U.S. Food and Drug Administration (FDA) approved a brain imaging test called DaTscan to help diagnose Parkinson's disease (PD). DaTscan is a specific type of single-photon emission computed tomography (SPECT) imaging technique that helps the diagnosis of PD. In Parkinson's, dopamine cells in the brain break down and die. DaTscan uses small amounts of a radioactive drug to light up dopamine transporters, which move the chemical dopamine into cells when it's done working. In people with Parkinson's, DaTscan appears different because there are fewer dopamine cells and therefore less dopamine transporter activity. The active substance in DaTSCAN, ioflupane (123I), is a radiopharmaceutical. It contains a substance called ioflupane, which is labeled with 123I (iodine-123), a radioactive form of the chemical element iodine. Ioflupane attaches specifically to structures on the surface of nerve cell endings in the striatum that are responsible for the transport of dopamine. When DaTSCAN is injected, ioflupane (123I) is distributed through the body in the blood and accumulates in the striatum, where it attaches to the structures that transport dopamine. 

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2021 Nobel Prize in Chemistry

 | Post date: 2021/10/7 | 
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The Nobel Prize in Physiology or Medicine 2021

 | Post date: 2021/10/4 | 
In a year when many may have expected the prize to go to at least one of the makers of a COVID-19 vaccine, molecular biologists have won the 2021 Nobel Prize in Physiology or Medicine for their discoveries of receptors for temperature and touch, the Nobel Committee has announced in Stockholm.
The 2021 Nobel Prize in Physiology or Medicine is awarded to David Julius and Ardem Patapoutian for their discoveries of receptors for temperature and touch.
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EOS: an appropriate imaging alternative that reduces radiation exposure!

 | Post date: 2021/09/27 | 
The EOS™ X-ray machine, based on a Nobel prize-winning invention in physics in the field of particle detection, is capable of a simultaneous capture of biplanar X-ray images by slot scanning of the whole body in an upright, physiological load-bearing position, using ultra-low radiation doses. The simultaneous capture of spatially calibrated anterioposterior and lateral images provides a three-dimensional (3D) surface reconstruction of the skeletal system using a special software. Parts of the skeletal system in X-ray images and 3D-reconstructed models appear in true 1:1 scale for size and volume, thus spinal and vertebral parameters, lower limb axis lengths and angles, as well as any relevant clinical parameters in orthopaedic practice can be very precisely measured and calculated. Visualisation of 3D reconstructed models in various views by sterEOS 3D software enables presentation of top view images to help analyse rotational conditions of lower limbs, joints and spine deformities in the horizontal plane, providing revolutionary novel possibilities in orthopaedic surgery, especially in spine surgery.
During an EOS exam, the patient stands or sits in an upright position inside a special scanning cabin. Two very narrow X-ray beams – one vertical, one horizontal – scan entire body to create 2D and 3D images of the spine and joints.
Unlike traditional X-ray imaging, where the patient may have to be repositioned to get views from different angles, these two simultaneous scans provide all the imaging necessary. Capturing frontal and lateral (side-view), full-body images takes less than twenty seconds. If a full-body image is not necessary (such as for a knee condition), the EOS system can be set to scan a particular region of the patient’s anatomy.
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The uncertain future of Covid 19: Multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019!

 | Post date: 2021/09/23 | 
The current knowledge about the COVID-19 (Coronavirus Disease-2019) pandemic is still limited and is unravelling with the passing days, especially clinical data, and research in pediatric age group. Recently, there is a new and crucial development reported recently among the COVID-19 asymptomatic children, a novel syndrome affecting asymptomatic COVID-19 children, presenting as a hyperinflammatory syndrome which is like Kawasaki disease shock syndrome. 
Multisystem inflammatory syndrome (MIS-C) is a pediatric hyperinflammation disorder caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It has now been reported from several countries the world over. Some of the clinical manifestations of MIS-C mimic Kawasaki disease (KD) shock syndrome. MIS-C develops 4–6 weeks following SARS-CoV-2 infection, and is presumably initiated by adaptive immune response. Though it has multisystem involvement, it is the cardiovascular manifestations that are most prominent. High titres of anti-SARS-CoV-2 antibodies are seen in these patients. As this is a new disease entity, its immunopathogenesis is not fully elucidated. Whether it has some overlap with KD is still unclear.
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Gamma scintigraphy: a non-invasive imaging technique!

 | Post date: 2021/09/20 | 
Scintigraphy is highly sensitive for lesion detection in various diseases. This non-invasive imaging technique provides a functional display of skeletal metabolism.
Furthermore, Scintigraphy is an option to assess the mobility of the entire gastrointestinal system. Although not as widely available, it is useful in the assessment of transit in the colon and proximal gut. Transit times obtained through scintigraphy are generated following consumption of a radiolabeled egg sandwich, and individual times are generated for the stomach, small bowel, and colon. These tests add value in surgical planning for slow transit constipation to ensure that the dysfunction is limited to the colon and does not affect the proximal gastrointestinal tract. 
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Positron emission tomography (PET) scan: an effective way to help identify cancer, heart disease and brain disorders!

 | Post date: 2021/09/16 | 
A positron emission tomography (PET) scan is an imaging test that can help reveal the metabolic or biochemical function of your tissues and organs. The PET scan uses a radioactive drug (tracer) to show both normal and abnormal metabolic activity. A PET scan can often detect the abnormal metabolism of the tracer in diseases before the disease shows up on other imaging tests, such as computerized tomography (CT) and magnetic resonance imaging (MRI).
The tracer is most often injected into a vein within your hand or arm. The tracer will then collect into areas of your body that have higher levels of metabolic or biochemical activity, which often pinpoints the location of the disease. The PET images are typically combined with CT or MRI and are called PET-CT or PET-MRI scans.

PET scan is an effective way to help identify a variety of conditions, including cancer, heart disease and brain disorders. Your doctor can use this information to help diagnose, monitor or treat your condition.
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X-Ray Fluorescence Spectroscopy

 | Post date: 2021/09/9 | 
X-ray fluorescence (XRF), which has been applied during the 1970s to 1990s, is based on the observation of (X-ray) photon emissions of atoms, which are induced into an excited state by irradiation with X-rays causing the removal of a core electron from the atom. The resulting inner shell vacancies are filled by electrons from outer shells of the same atom. The difference in energy between the two electron orbitals appears as an emitted X-ray photon, which can be measured with an X-ray spectrometer.
The technology used for the separation (dispersion), identification and intensity measurement of a sample's X-ray fluorescence spectrum gives rise to two main types of spectrometer: wavelength dispersive (WDXRF) and energy dispersive (EDXRF) systems.
In WDXRF spectrometers, the X-ray tube acting as a source irradiates a sample directly, and the fluorescence coming from the sample is measured with a wavelength dispersive detection system. The characteristic radiation coming from each individual element can be identified using analyzing crystals which separate the X-rays based on their wavelength, or conversely their energies.
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