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151.
Virus-induced cytokines regulate circulating lymphocyte levels during primary SIV infections 总被引:1,自引:0,他引:1
Rosenberg YJ; Cafaro A; Brennan T; Greenhouse JG; Villinger F; Ansari AA; Brown C; McKinnon K; Bellah S; Yalley-Ogunro J; Elkins WR; Gartner S; Lewis MG 《International immunology》1997,9(5):703-712
Decline in blood CD4+ lymphocytes during primary symptomatic infections
with HIV is usually attributed to viral killing, and has not been
considered in terms of altered lymphocyte migration and sequestration. We
therefore sought to examine whether CD4+ cell loss from blood of macaques
undergoing an acute primary SIV infection might be due to increased
synthesis of cytokines, known to profoundly affect lymphocyte trafficking,
rather than to direct lymphocyte destruction by virus. The findings
indicate that rapid lymphocyte depletion following acute infection is not
selective for CD4+ cells, correlates precisely with increased plasma
IFN-gamma and tumor necrosis factor-alpha levels, and is reversible.
CD4/CD8 ratios in lymph nodes with high viral burdens remain relatively
unchanged despite lymphocyte loss from blood. Levels of cytokine mRNA
measured in lymphoid organs reflect neither cytokine plasma levels nor
their potential to induce sequestration. These results support a model of
cytokine-induced lymphocyte extravasation to account for the acute
HIV/SIV-induced CD4+ cell lymphopenia and raise questions regarding the
extent to which altered lymphocyte migration plays a role in the gradual
CD4+ cell depletion throughout infection.
相似文献
152.
Queenie Fernandes Varghese Philipose Inchakalody Maysaloun Merhi Sarra Mestiri Nassiba Taib Dina Moustafa Abo El-Ella Takwa Bedhiafi Afsheen Raza Lobna Al-Zaidan Mona O. Mohsen Mariam Ali Yousuf Al-Nesf Ali Ait Hssain Hadi Mohamad Yassine Martin F. Bachmann Shahab Uddin Said Dermime 《Annals of medicine》2022,54(1):524
The emergence of novel and evolving variants of SARS-CoV-2 has fostered the need for change in the form of newer and more adaptive diagnostic methods for the detection of SARS-CoV-2 infections. On the other hand, developing rapid and sensitive diagnostic technologies is now more challenging due to emerging variants and varying symptoms exhibited among the infected individuals. In addition to this, vaccines remain the major mainstay of prevention and protection against infection. Novel vaccines and drugs are constantly being developed to unleash an immune response for the robust targeting of SARS-CoV-2 and its associated variants. In this review, we provide an updated perspective on the current challenges posed by the emergence of novel SARS-CoV-2 mutants/variants and the evolution of diagnostic techniques to enable their detection. In addition, we also discuss the development, formulation, working mechanisms, advantages, and drawbacks of some of the most used vaccines/therapeutic drugs and their subsequent immunological impact.
Key message
- The emergence of novel variants of the SARS-CoV-2 in the past couple of months, highlights one of the primary challenges in the diagnostics, treatment, as well as vaccine development against the virus.
- Advancements in SARS-CoV-2 detection include nucleic acid based, antigen and immuno- assay-based and antibody-based detection methodologies for efficient, robust, and quick testing; while advancements in COVID-19 preventive and therapeutic strategies include novel antiviral and immunomodulatory drugs and SARS-CoV-2 targeted vaccines.
- The varied COVID-19 vaccine platforms and the immune responses induced by each one of them as well as their ability to battle post-vaccination infections have all been discussed in this review.
153.
Trinucleotide expansion mutations in the cartilage oligomeric matrix protein (COMP) gene 总被引:6,自引:1,他引:5
Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are
two human autosomal dominant skeletal dysplasias characterized by variable
short stature, joint laxity and early-onset degenerative joint disease.
Both disorders can result from mut-ations in the gene for cartilage
oligomeric matrix protein (COMP), an extracellular matrix glycoprotein.
About one-third of PSACH cases result from heterozygosity for deletion of
one codon within a very short triplet repeat, (GAC)5, which encodes five
consecutive aspartic acid residues within the calmodulin-like region of the
COMP protein. We have identified two expansion mut-ations in this repeat:
an MED patient carrying a (GAC)6allele and a PSACH patient carrying a
(GAC)7allele. These are among the shortest disease-causing triplet repeat
expansion mutations described thus far, and are the first identified in a
GAC repeat. A unique feature of this sequence is that expansion as well as
shortening of the repeat can cause the same disease. In cartilage, both
patients have rough endoplasmic reticulum inclusions in chondrocytes. The
inclusions are also present in tendon tissue and can be reproduced in
cultured tendon cells, suggesting that the pathophysiology of disease is
similar in both cartilage and tendon.
相似文献
154.
The potential of magnetic resonance (MR) imaging to demonstrate the mediastinal veins was evaluated retrospectively in 25 patients with no evidence of a venous abnormality, 28 patients who had narrowing or occlusion of a mediastinal vein, and two patients who had a venous anomaly. In patients with venous occlusion, the MR images graphically demonstrated the sites and extent. MR images also demonstrated slow flow within venous structures proximal to the obstruction. Generally, venous collaterals in the mediastinum and chest wall were better seen with contrast material-enhanced computed tomography scans. The marked contrast on MR images between the signal void of normal vascular structures, the moderate signal intensity of tumor, and the high signal intensity of a thrombus or slowly flowing blood allows ready detection of venous occlusion and may suggest the nature of the occlusion. 相似文献
155.
Detection of pulmonary nodules using spin-echo magnetic resonance (MR) imaging was compared with detection using computed tomography (CT). Of the 25 patients studied independently by two radiologists, no lung nodules were detected in 11 (CT or MR), ten had a single nodule, and four had multiple nodules. The lesions not seen using CT or MR were less than 1.3 cm in diameter. The greater spatial resolution of CT enabled better detection of nodules close to the diaphragm, the pleura, or to each other, whereas the better contrast resolution of MR enabled the detection of several nodules close to blood vessels. With MR, nodules were best seen on images with long repetition times (2.0 sec). Most pulmonary nodules are seen using both CT and MR. CT generally enables the detection of more small nodules than MR does, and some low-density nodules near blood vessels are better displayed using MR. 相似文献
156.
157.
We describe a new pyeloureteral drainage catheter that can be used for both genitourinary tract stenting and drainage, as well as tamponade of bleeding from the renal parenchyma or subcutaneous tissue. Primary indications for the use of this catheter and recommendations on insertion techniques are presented. With the exception of one case of minor kinking of the catheter, we have had no complications or failures with this catheter. While insertion through an unprotected tissue track is somewhat difficult, we have had good success introducing the catheter through a 24-F or larger Teflon working sheath. The catheter has excellent patient retention properties. It can be converted from external to internal drainage or vice versa simply and quickly on the ward. 相似文献
158.
159.
160.
Anemone?van den BergEmail author Ruurd?M?van Elburg Jos?WR?Twisk Willem?PF?Fetter 《BMC pediatrics》2004,4(1):17