12-06-2021-1154 - Transverse myelitis (TM)

 Transverse myelitis (TM) is a rare neurological condition in which the spinal cord is inflamed. Transverse implies that the inflammation extends horizontally across the spinal cord.^[1] Partial transverse myelitis and partial myelitis are terms sometimes used to specify inflammation that only affects part of the width of the spinal cord.^[1] TM is characterized by weakness and numbness of the limbs, deficits in sensation and motor skills, dysfunctional urethral and anal sphincter activities, and dysfunction of the autonomic nervous system that can lead to episodes of high blood pressure. Signs and symptoms vary according to the affected level of the spinal cord. The underlying cause of TM is unknown. The spinal cord inflammation seen in TM has been associated with various infections, immune system disorders, or damage to nerve fibres, by loss of myelin.^[1] As opposed to leukomyelitis which affects only the white matter, it affects the entire cross-section of the spinal cord.^[3] Decreased electrical conductivity in the nervous system can result.^{[citation needed]}

An MRI showing a transverse myelitis lesion, which is lighter, oval shape at center-right. The patient recovered 3 months later.

^{https://en.wikipedia.org/wiki/Transverse_myelitis}

12-06-2021-1153 - Bronchiolitis obliterans (BO)

 Bronchiolitis obliterans (BO), also known as obliterative bronchiolitis, constrictive bronchiolitis and popcorn lung, is a disease that results in obstruction of the smallest airways of the lungs (bronchioles) due to inflammation.^[1][6] Symptoms include a dry cough, shortness of breath, wheezing and feeling tired.^[1] These symptoms generally get worse over weeks to months.^[4] It is not related to cryptogenic organizing pneumonia, previously known as bronchiolitis obliterans organizing pneumonia.^[4]

Causes include breathing in toxic fumes, respiratory infections, connective tissue disorder or complications following a bone marrow or heart-lung transplant.^[1] Symptoms may not occur until two to eight weeks following toxic exposure or infection.^[1] The underlying mechanism involves inflammation that results in scar tissue formation.^[1] Diagnosis is by CT scan, pulmonary function tests or lung biopsy.^[1] A chest X-ray is often normal.^[4]

While the disease is not reversible, treatments can slow further worsening.^[1] This may include the use of corticosteroids or immunosuppressive medication.^[1] A lung transplant may be offered.^[4] Outcomes are often poor, with most people dying in months to years.^[4]

Bronchiolitis obliterans is rare in the general population.^[4] It, however, affects about 75% of people by ten years following a lung transplant and up to 10% of people who have received a bone marrow transplant from someone else.^[4] The condition was first clearly described in 1981.^[4] Prior descriptions occurred as early as 1956, with the term "bronchiolitis obliterans" used first by Reynaud in 1835.^[7][8]

Other names	Constrictive bronchiolitis,[2]Obliterative bronchiolitis, Popcorn lung
High resolution CT scan showing bronchiolitis obliterans with mosaic attentuation, bronchiectasis, air trapping and bronchial thickening[3]

https://en.wikipedia.org/wiki/Bronchiolitis_obliterans

12-06-2021-1153 - genetic chimerism or chimera

 A genetic chimerism or chimera (/kaɪˈmɪərə/ ky-MEER-ə or /kɪˈmɪərə/ kə-MEER-ə) is a single organism composed of cells with more than one distinct genotype. In animals, this means an individual derived from two or more zygotes, which can include possessing blood cells of different blood types, subtle variations in form (phenotype) and, if the zygotes were of differing sexes, then even the possession of both female and male sex organs^[1] (this is just one of many different phenomena that may result in intersexuality). Animal chimeras are produced by the merger of multiple fertilized eggs. In plant chimeras, however, the distinct types of tissue may originate from the same zygote, and the difference is often due to mutation during ordinary cell division. Normally, genetic chimerism is not visible on casual inspection; however, it has been detected in the course of proving parentage.^[2]

Another way that chimerism can occur in animals is by organ transplantation, giving one individual tissues that developed from a different genome. For example, transplantation of bone marrow often determines the recipient's ensuing blood type.^{[citation needed]}

^{https://en.wikipedia.org/wiki/Chimera_(genetics)}

12-06-2021-1150 - 4963/4-5,6

12-06-2021-1150 - 4963/4-5,6

12-06-2021-1149 - viral vectors

 Viral vectors are tools commonly used by molecular biologists to deliver genetic material into cells. This process can be performed inside a living organism (in vivo) or in cell culture (in vitro). Viruses have evolved specialized molecular mechanisms to efficiently transport their genomes inside the cells they infect. Delivery of genes or other genetic material by a vector is termed transduction and the infected cells are described as transduced. Molecular biologists first harnessed this machinery in the 1970s. Paul Berg used a modified SV40 virus containing DNA from the bacteriophage λ to infect monkey kidney cells maintained in culture.^[1]

In addition to their use in molecular biology research, viral vectors are used for gene therapy and the development of vaccines.

https://en.wikipedia.org/wiki/Viral_vector

12-06-2021-1148 - gene transplantation vector

Gene therapy utilizes the delivery of DNA into cells, which can be accomplished by several methods, summarized below. The two major classes of methods are those that use recombinant viruses (sometimes called biological nanoparticles or viral vectors) and those that use naked DNA or DNA complexes (non-viral methods).

https://en.wikipedia.org/wiki/Vectors_in_gene_therapy

Monday, September 6, 2021

09-06-2021-0927 - Mobile genetic elements (MGEs) sometimes called selfish genetic elements transposable element (TE, transposon, or jumping gene

 

12-06-2021-1145 - modification of genetic information

Subcategories

This category has the following 5 subcategories, out of 5 total.

G

•  Gene delivery‎ (1 C, 27 P)
•  Genetic engineering‎ (12 C, 115 P)

M

•  Mobile genetic elements‎ (2 C, 47 P)
•  Mutagenesis‎ (15 P)
•  Mutation‎ (8 C, 106 P)

Pages in category "Modification of genetic information"

The following 29 pages are in this category, out of 29 total. This list may not reflect recent changes (learn more).

A

• Alternative Lengthening of Telomeres

B

• Bacterial conjugation
• Bacterial recombination

C

• Chromosomal crossover
• Chromosomal inversion
• Chromosomal translocation

D

• De novo gene birth
• Deletion (genetics)

E

• Ectopic recombination

G

• Gene conversion
• Gene duplication
• Genetic recombination

H

• Homologous recombination

L

• Loss of heterozygosity

M

• Missense mutation
• Mitotic recombination

N

• Nonsense mutation

P

• Paramutation
• Point mutation
• Postzygotic mutation

R

• Chromosomal rearrangement
• Recombinase
• Retrovirus

S

• Silent mutation
• Sister chromatid exchange

T

• Tissue nanotransfection
• Transduction (genetics)
• Transformation (genetics)
• Transposable element

 https://en.wikipedia.org/wiki/Category:Modification_of_genetic_information

12-06-2021-1144 - inversion

 An inversion is a chromosome rearrangement in which a segment of a chromosome is reversed end-to-end. An inversion occurs when a single chromosome undergoes breakage and rearrangement within itself. Inversions are of two types: paracentric and pericentric.

Paracentric inversions do not include the centromere, and both breaks occur in one arm of the chromosome. Pericentric inversions include the centromere, and there is a break point in each arm.

Cytogenetic techniques may be able to detect inversions, or inversions may be inferred from genetic analysis. Nevertheless, in most species, small inversions go undetected. In insects with polytene chromosomes (for example, Drosophila), preparations of larval salivary gland chromosomes allow inversions to be seen when they are heterozygous. This useful characteristic of polytene chromosomes was first advertised by Theophilus Shickel Painter in 1933.^[1]

Inversions usually do not cause any abnormalities in carriers, as long as the rearrangement is balanced, with no extra or missing DNA. However, in individuals which are heterozygous for an inversion, there is an increased production of abnormal chromatids (this occurs when crossing-over occurs within the span of the inversion). This leads to lowered fertility, due to production of unbalanced gametes. An inversion does not involve a loss of genetic information, but simply rearranges the linear gene sequence.

Families that may be carriers of inversions may be offered genetic counseling and genetic testing.^[2]

In the species Drosophila subobscura, researchers have been able to track global climate change by measuring the magnitude and directional shift in chromosome inversion frequencies, relative to temperatures at specific global sites.^[3]

An example of chromosomal Inversion in organisms is demonstrated in the insect, Coelopa frigida. This particular species of Coelopa have a variation of chromosomal inversions that allow the species to create a series of physical differences. Individual C. frigida that are larger do not undergo a chromosomal inversion, whereas individuals that are smaller do undergo a chromosomal inversion.

A clay model showing why heterozygous inversion loops are visible in polytene chromosome preparations

An inversion loop in the A arm of a chromosome from an Axarus species midge

https://en.wikipedia.org/wiki/Chromosomal_inversion

12-06-2021-1143 - Hypodiploid acute lymphoblastic leukemia

 Hypodiploid acute lymphoblastic leukemia is the chromosome mutation of leukemic cells with 45 chromosomes or less. It has been determined that the prognosis of hypodiploid is much less than standard acute lymphoblastic leukemia.^[1] The lower the chromosome count, the lower the survival rate. In a study documented by the American Society of Hematology 17 of 27 patients relapsed, which indicates poor treatment responsiveness of hypodiploid ALL.^[2] Hypodiploid is an unfavorable karyotypic feature in childhood ALL.^[3]

https://en.wikipedia.org/wiki/Hypodiploid_acute_lymphoblastic_leukemia

12-06-2021-1142 - Acute lymphoblastic leukemia (ALL)

 Acute lymphoblastic leukemia (ALL) is a cancer of the lymphoid line of blood cells characterized by the development of large numbers of immature lymphocytes.^[1] Symptoms may include feeling tired, pale skin color, fever, easy bleeding or bruising, enlarged lymph nodes, or bone pain.^[1] As an acute leukemia, ALL progresses rapidly and is typically fatal within weeks or months if left untreated.^[11]

In most cases, the cause is unknown.^[2] Genetic risk factors may include Down syndrome, Li-Fraumeni syndrome, or neurofibromatosis type 1.^[1]Environmental risk factors may include significant radiation exposure or prior chemotherapy.^[1] Evidence regarding electromagnetic fields or pesticides is unclear.^[4][6] Some hypothesize that an abnormal immune response to a common infection may be a trigger.^[4] The underlying mechanism involves multiple genetic mutations that results in rapid cell division.^[2] The excessive immature lymphocytes in the bone marrow interfere with the production of new red blood cells, white blood cells, and platelets.^[1] Diagnosis is typically based on blood tests and bone marrow examination.^[3]

ALL is typically treated initially with chemotherapy aimed at bringing about remission.^[2] This is then followed by further chemotherapy typically over a number of years.^[2] Treatment usually also include intrathecal chemotherapy since systemic chemotherapy can have limited penetration into the central nervous system and the central nervous system is a common site for relapse of acute lymphoblastic leukemia.^[12][13]

Treatment can also include radiation therapy if spread to the brain has occurred.^[2] Stem cell transplantation may be used if the disease recurs following standard treatment.^[2] Additional treatments such as Chimeric antigen receptor T cell immunotherapy are being used and further studied.^[2]

ALL affected about 876,000 people globally in 2015 and resulted in about 111,000 deaths.^[14][10] It occurs most commonly in children, particularly those between the ages of two and five.^[15][4] In the United States it is the most common cause of cancer and death from cancer among children.^[2] ALL is notable for being the first disseminated cancer to be cured.^[16] Survival for children increased from under 10% in the 1960s to 90% in 2015.^[2] Survival rates remain lower for babies (50%)^[17] and adults (35%).^[8] According to the National Cancer Intelligence Network (NCIN), generally for people with ALL: around 70 out of 100 people (70%) will survive their leukemia for 5 years or more after they are diagnosed.

Other names	Acute lymphocytic leukemia, acute lymphoid leukemia
Bone marrow aspirate smear from a person with precursor B-cell ALL. The large purple cells are lymphoblasts.

https://en.wikipedia.org/wiki/Acute_lymphoblastic_leukemia