Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Encapsulated bacteria such as Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae serogroup B (Hib) are a major cause of disease worldwide. Vaccine development against these organisms has targeted their capsular polysaccharides (CPS), as anti-capsular antibodies often protect against disease. The capsular polysaccharide vaccines that have been available against these organisms are neither immunogenic nor protective in young children and certain immunocompromised individuals. In general, polysaccharide (PS) antigens elicit a T-independent immune response, characterized by lack of memory, and poor immunogenicity at the extremes of life. Efforts to overcome the poor immunogenicity of CPS vaccines have led to development of conjugate vaccines. By conjugating CPS to carrier proteins it is possible to induce a T-dependent immune response against these antigens. Although conjugate vaccines have been successful against Hib disease, their applicability to multi-serotype/serogroup pathogens like the pneumococcus or the meningococcus is questioned. As a result, alternative vaccines including (1) surface proteins conserved across serotypes/serogroups, (2) peptides that mimic PS antigens and (3) DNA vaccines are presently under investigation. This review will highlight the potential and limitations of both CPS and CPS-conjugate vaccines against encapsulated bacteria as well as alternative strategies against PS antigens.
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PMID:Vaccines against polysaccharide antigens. 1245 5

Splenectomy, while often necessary in otherwise healthy patients after major trauma, finds its primary indication for patients with underlying malignant or nonmalignant hematologic diseases. Indications of splenectomy for hematologic diseases have been reducing in the last few years, due to improved diagnostic and therapeutic tools. In high-income countries, there is a clear decrease over calendar time in the incidence of all indication splenectomy except nonmalignant hematologic diseases. However, splenectomy, even if with different modalities including laparoscopic splenectomy and partial splenectomy, continue to be a current surgical practice both in nonmalignant hematologic diseases, such as Immune Thrombocytopenic Purpura (ITP), Autoimmune Hemolytic Anemia (AIHA), Congenital Hemolytic Anemia such as Spherocytosis, Sickle Cell Anemia and Thalassemia and Malignant Hematological Disease, such as lymphoma. Today millions of people in the world are splenectomized. Splenectomy, independently of its cause, induces an early and late increase in the incidence of venous thromboembolism and infections. Infections remain the most dangerous complication of splenectomy. After splenectomy, the levels of antibody are preserved but there is a loss of memory B cells against pneumococcus and tetanus, and the loss of marginal zone monocytes deputed to immunological defense from capsulated bacteria. Commonly, the infections strictly correlated to the absence of the spleen or a decreased or absent splenic function are due to encapsulated bacteria that are the most virulent pathogens in this set of patients. Vaccination with polysaccharide and conjugate vaccines again Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis should be performed before the splenectomy. This practice reduces but does not eliminate the occurrence of overwhelming infections due to capsulated bacteria. At present, most of infections found in splenectomized patients are due to Gram-negative (G-) bacteria. The underlying disease is the most important factor in determining the frequency and severity of infections. So, splenectomy for malignant diseases has the major risk of infections.
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PMID:Bacterial Infections Following Splenectomy for Malignant and Nonmalignant Hematologic Diseases. 2654 26