Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seventy five patients with large spleens were investigated in order to establish the causes of splenomegaly in Northern Nigeria, to define further the diagnostic criteria of tropical splenomegaly syndrome (TSS), and to study its pathogenesis. Investigations included examination of liver biopsy, bone marrow cytology, lymphocyte response to phytohaemagglutinin (PHA), serum immunoglobulins and complement, and the presence of immunoglobulin and complement fixed in Kupffer cells. Thirty patients had TSS, five chronic lymphatic leukaemia (CLL), four a syndrome of gross lymphoid hyperplasia (GLH) distinct from TSS, CLL and the lymphomas, and twenty three miscellaneous conventional diseases. In thirteen cases no definite diagnosis could be established. TSS was found to be predominantly a disease of female Fulani cattle herders. Its essential characteristics were splenomegaly in the presence of acquired immunity to malaria, a grossly raised serum IgM, a lowered serum complement, and the presence of IgM fixed in Kupffer cells. There was lymphoid hyperplasia in bone marrow, hepatic sinusoids and often blood which may be indistinguishable from that in CLL. Lymphocytes undergo normal blastogenesis to PHA. There was clinical and haematological response to proguanil therapy. Reticuloendothelial phagocytosis of IgM, probably as a complex, seems to be the essential feature of the condition. As it was impossible to identify early cases of TSS it is unclear whether IgM overproduction or phagocytosis of IgM complexes is the first stage of the disease. The precise nature of the association with malaria remains obscure. The diagnosis of CLL demanded the demonstration of an abnormally low immunoglobulin level and impaired lymphocyte responsiveness to PHA by blast transformation or 3H-thymidine incorporation, in addition to the usual haematological findings. The syndrome GLH occurred in multiparous Hausa women. It was characterised by intense lymphocytosis with active, PHA-responsive cells, and normal immunoglobulin levels. Patients responded to proguanil therapy. It is suggested that these patients have a depressed immune response to malaria, perhaps through repeated pregnancies, and to a leukaemogenic agent, both of which stimulate lymphocytosis. Antimalarial treatment at this stage may prevent the development of frank leukaemia or lymphoma. The usefulness of the various investigative procedures and the problem of managing the large number of undiagnosed cases are discussed.
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PMID:Splenomegaly in Northern Nigeria. 1 54

Burkitt's lymphoma occurs mainly in parts of tropical Africa and has attracted the attention of experimental workers due to its epidemiological and clinical features, which indicate a viral etiology and a host immune response to the tumor. As a result of virological studies, Epstein-Barr virus (EBV) DNA has been demonstrated in almost all tested biopsies of African BL. This contrasts to the absence of EBV in all, or almost all, of the non-African Burkitt's lymphoma-like tumors, even though the number of tested tumors in this group is small, and to the lack of EBV in all other types of lymphoma or leukemia. Immunological studies have revealed the presence of antibodies to different EBV-associated antigens in all African patients with Burkitt's lymphoma. However the antibodies are not specific for Burkitt's lymphoma but are found in most adults all over the world, although at lower levels. They cannot therefore serve diagnostic purposes, but they can give prognostic information and occasionally give clues to the mechanisms behind late tumor recurrences, and possibly guide so-called immunotherapy. Burkitt's lymphoma patients contrast to appropriate control groups where some of the persons are anti-EBV seronegative, and this, together with the presence of EBV in Burkitt's lymphoma biopsies and the absence of EBV in other lymphomas, even though the cell type involved may be infectable by EBV in vitro and the tumor may arise in an EBV-carrying person, favors an etiological role in EBV in Burkitt's lymphoma and speaks against the "passenger" hypothesis, according to which EBV is picked up by the Burkitt's lymphoma cell which happens to be particularly suitable for EBV persistence. To explain the geographical distribution, a cofactor, such as certain forms of malaria, has been implied.
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PMID:Burkitt's lymphoma - a human tumor model system for immunological studies. 17 35

In a controlled study in Ghana, the hemoglobin electrophoretic pattern in 112 patients with Burkitt's lymphoma was compared to that of their nearest neighbor controls of the same age, sex, and tribe, as well as their sibling controls. Analysis of the data obtained did not show any statistically significant protective advantage for sickle cell trait against Burkitt's lymphoma. Hemoglobin C trait appeared to offer a slight protective advantage (p less than 0.1), but this did not reach statistical significance. These results do not disprove the malaria co-factor hypothesis in the etiology of 0urkitt's lymphoma, but deprive it of an additional indirect evidence in its favor.
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PMID:Sickle cell trait, hemoglobin C trait, and Burkitt's lymphoma. 96 85

Membranous nephropathy (MN) accounts for about 20 percent of cases of the nephrotic syndrome. The importance of renal biopsy in establishing the diagnosis is emphasized. In the great majority of MN patients, no etiologic factor can be discerned. In a significant minority, MN appears to be a manifestation of sarcoidosis, diabetes, lupus, syphilis, malaria, or toxicity from heavy metals or drugs. In some cases the "cause" is neoplasia (including lymphoma) or a viral infection. Massive proteinuria, hypoproteinemia and edema are the principal manifestations of MN, finally resulting in renal failure. Treatment consists chiefly of diet and diuretic drugs. In the more pronounced cases, corticosteroids may have a favorable effect and in very resistant cases, cyclophosphamide is indicated. Judicious use of these modalities if often associated with the diminution or disappearance of the clinical signs of MN.
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PMID:Membranous nephropathy: an overview. 120 87

A hypothesis which explains disease prevalence among different socio-economic groups following early infantile modulation of cell-mediated immunity by infection and nutrition related stress is presented. Wealthy populations living under highly hygienic circumstances can develop their cell-mediated immunity to genetic expectation while their humoral systems remains unstimulated. Primitive populations protect the infant's immune development by breast feeding and suffer from temporary cell-mediated immune deficiencies due to intercurrent infectious disease and famine later on. Intermediary populations harbour a small percentage of people, whose cell-mediated immune system has been permanently damaged by infection in early childhood, leading to a high incidence of diseases linked to cell-mediated immune deficiency. The possible cocarcinogenesis of the cell-mediated immune deficiency following repeated gastroenteritis and persistent stimulation of B cells, leading to alpha heavy chain disease and primary intestinal lymphoma, or due to falciparum malaria in newborns and its impact on the EB virus genome in development of Burkitt's lymphoma, are discussed.
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PMID:Immune modulation and disease patterns in population groups. 122 70

Discovery of an enlarged spleen in a child requires steps to identify the etiology. One hundred and seventy-eight patients seen over a four-year period (1985-1988) at the Cocody Teaching Hospital were reviewed. The incidence of splenic enlargement among pediatric inpatients was 1.6%. Males (n = 106) were more often affected than females (n = 72). Slightly over half the children (54.49%) were 0 to 5 years of age. The main clinical presenting features were fever (90%), anemia (72%), a decline in general health (36.50%), enlargement of the liver (33.50%), jaundice (26.50%), and enlarged lymph nodes (7%). Type II of Hackett's classification accounted for most cases (61.80%), followed by Type III (14%). Main etiologies included malaria (53%), salmonella infections (15%), sickle cell anemia (14%), schistosomiasis (9%), AIDS (3%), and thalassemia (2%). Malignancies (leukemia, lymphoma) were relatively infrequent. More than one etiology was found in 13 cases. The distribution of etiologies by age group was determined and a strategy for investigating children with splenic enlargement in tropical countries was developed.
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PMID:[Etiology of splenomegaly in children in the tropics. 178 cases reviewed at the university hospital center of Abidjan-Cocody (Ivory Coast)]. 131 90

The function of c-myc in physiology is only partially known. Its product has DNA binding properties and plays a role in the control of proliferation and differentiation. In general, increased c-myc expression leads to proliferation and abolishment of differentiation. The involvement of c-myc in mouse plasmacytomas and human Burkitt's lymphoma is well known: due to chromosomal translocation c-myc comes under the influence of regulatory elements of immunoglobulin genes, leading to increased expression of the gene and proliferation of the cells. In man, the chromosomal translocations may occur within the increased pool of (pre) B-cells due to Epstein Barr virus (EBV) and malaria infection with subsequent immunosuppression. Apart from these early (primary?) events in lymphomagenesis, c-myc is also often involved in tumour progression, probably by a similar mechanism. Different types of c-myc involvement are associated with specific types of lymphoma: there are differences between endemic, sporadic and ileocecal Burkitt's lymphoma as well as between those and primary extranodal large cell lymphoma and large cell lymphoma which has progressed. These differences are associated with the differentiation of the involved lymphoid cells and may point to the stage of differentiation in which the oncogenic event occurred.
Leuk Lymphoma 1992 Aug
PMID:The association of c-myc rearrangements with specific types of human non-Hodgkin's lymphomas. 149 39

Burkitt's lymphoma is the most common childhood cancer in Africa. Most prevalent in areas endemic for malaria, the disease, a malignant growth of lymphoid tissue, usually presents itself as a large tumour of the jaw. When first characterized in the 1950s, the lymphoma was thought to spread by some infectious agent. Subsequent research indicates that the frequent involvement of an infectious agent is but one factor in a more complex aetiology. Today, Burkitt's lymphoma is considered an example of multistep carcinogenesis. Each step in the process results from a different agent. The agent in the first step is the Epstein-Barr virus, which infects B cells of the immune system causing a proliferation of these cells. The second step, malarial infection, furthers the proliferation of B cells providing a large population of cells available for a chromosomal translocation which represents the third step in the formation of the lymphoma. The chromosomal translocation places a cancer causing gene, c-myc, in close proximity to an active antibody-encoding its proliferation resulting in a cell capable of unlimited growth which serves as the nucleus of a B cell lymphoma.
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PMID:Burkitt's lymphoma and the role of Epstein-Barr virus. 216 60

Epstein-Barr virus and HTLV-1 are both lymphotropic viruses, capable of immortalizing lymphocytes in vitro (Fig. 1). Both viruses have been sequenced and subjected to intense molecular biologic scrutiny, and in both cases genes believed to be important in lymphocyte immortalization have been identified. These viral genes are not homologues of cellular oncogenes, nor is there any evidence to suggest insertional mutagenesis. Rather, these genes alter the expression of a variety of cellular genes and, in so doing, alter the growth characteristics of the host cell. Infection with either virus is most likely to be asymptomatic, associated with a benign self-limited lymphoproliferation, or both, but in a small fraction of instances these benign lymphoproliferations give rise to a lymphoma or leukemia. In the case of the Epstein-Barr virus, a variety of cofactors have been identified that are important to the evolution of malignancy. These cofactors include immunosuppression in transplant recipients, cogenital immunodeficiency in the X-linked lymphoproliferative syndrome, human immunodeficiency virus infection in AIDS patients, and malaria in patients with endemic Burkitt's lymphoma. In the case of HTLV-1, cofactors have not been identified. Nonetheless, the importance of cofactors is suggested by the small fraction of the population infected by the virus who actually develop lymphoproliferative disease, and the long latency period between infection and the development of frank lymphoproliferative disease. In organ transplant recipients with lymphomas associated with Epstein-Barr virus infection, the EBV immortalizing/transforming genes are expressed in the malignant tissue. But in Burkitt's lymphoma and in adult T-cell leukemia/lymphoma, the EBV and HTLV-1 immortalizing/transforming genes are not detectably expressed. In Burkitt's lymphoma, it is suggested that the dysregulated myc gene renders the growth effects of Epstein-Barr virus latency genes superfluous. No comparable proto-oncogene translocation or activation has yet been identified in HTLV-1 lymphoma/leukemia.
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PMID:Human lymphotropic viruses associated with lymphoid malignancy: Epstein-Barr and HTLV-1. 217 3

This review describes the transmission, clinical picture and immunological abnormalities of HIV infection in children in general, and the special problems of AIDS in African children. The review begins with a thorough introduction to the epidemiology of AIDS. Transmission to children generally involves vertical transmission by placental transfer or transmission of HIV via transfusion of blood and blood products, or by contaminated needles. Casual transfer is unknown, and only a few cases of transmission via breast milk are known. The clinical picture of HIV infection in infants and children differs from that in adults in 3 important aspects: earlier onset, different clinical presentation and existence of AIDS embryopathy. The average onset was 5 months of age. The most common symptoms in young children are chronic interstitial pneumonitis without demonstrable etiology, hepatomegaly, failure to thrive, adenopathy, diarrhea, oral or perineal thrush, eczema and thrombocytopenia. The common opportunistic infections are pneumocystis carinii pneumonia, cytomegalovirus, Epstein-Barr virus, Cryptosporidium diarrhea, pyogenic infections of the middle ear and gram-negative septicemia. Several infections seen in adult AIDS cases are rare in children: mycobacterium avium-intracellulare, toxoplasma gondii, hepatitis B, as well as Kaposi's sarcoma, malignant lymphoma and cardiac abnormalities. The AIDS embryopathy or HIV dysmorphic syndrome is characterized by immunological abnormalities, growth failure, and craniofacial dysmorphism, particularly microcephaly, prominent box-like forehead, hypertelorism, flattened nasal bridge, obliquity of the eyes, blue sclerae and patulous lips. AIDS in African children is extremely difficult to diagnose because of similarities between the presenting symptoms and those commonly seen in sick children there, many of whom are also immune compromised. Where serotesting is available, the picture is complicated by cross reaction between the test agents and some factor found in sera from malaria patients. Seropositivity in some areas is high, increased by the prevalence of transfusion and injection treatments. Diagnosis is made more difficult by lack of laboratory facilities and difficulties in follow-up for pediatric patients. The CDC definitions of AIDS and ARC, and the WHO/CDC definitions of AIDS are appended.
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PMID:Human immunodeficiency virus infection in childhood. 245 15


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