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J Arellano

Publications and source records attributed to J Arellano.

At least 37 records · Page 2Linked to original sources
PubMed1992

The destruction of virulent Entamoeba histolytica by activated human eosinophils.

Unlike normal (i.e., non-activated) human eosinophils that are unable to destroy virulent Entamoeba histolytica even in the presence of antibodies and complement, activated eosinophils effectively destroy the parasite in vitro without the help of opsonins, yet increase this capacity with their assistance. Many activated eosinophils succumb in the process as well, probably victims of toxic products released by dying amoebae. Human activated eosinophils thus behave more like activated macrophages than like neutrophil polymorphonuclear leucocytes that are notoriously incompetent in dealing with virulent amoebae. As a regular constituent of early inflammatory reactions, and notwithstanding the absence of blood and tissue eosinophilia in invasive amoebiasis, the activated eosinophil may play a role in the defence against E. histolytica.

Adult↗
PubMed1992

The killing of Entamoeba histolytica by activated human eosinophils.

Unlike normal, opsonin aided human eosinophils, fMLP-activated human eosinophils are capable of destroying virulent E. histolytica. Opsonins are not required for this action, although they enhance the effect. Some activated eosinophils succumb in the action as well, probably victims of toxic products released by dying amebas. Activated eosinophils thus appear to resemble activated macrophages in their dealing with this parasite.

Adult↗
PubMed1992

Increased frequency of HLA-DR3 in Mexican mestizo pediatric patients with amebic liver abscess (ALA).

Mexican mestizo pediatric patients with ALA revealed a significantly increased frequency of HLA-DR3 alone, or in its haplotype form HLA-A2, DR3, which confirms our previous observation in adult patients with ALA in the same ethnic group. However, the relative increase in these HLA specificities in pediatric ALA patients when compared to adult patients was not statistically significant, and calls for an enlargement of the population studied.

Adolescent↗
PubMed1991

The role of mannose in the receptor of the monocyte locomotion inhibitory factor produced by Entamoeba histolytica.

The effect of the monocyte locomotion inhibitory factor (MLIF) produced by Entamoeba histolytica is diminished, if not cancelled, when human monocytes are pre-exposed to concanavalin A or sodium periodate, respectively, but not when MLIF is pretreated with sodium periodate. When the MLIF-inhibited monocyte locomotion assays were performed in the presence of 12 different carbohydrates, only the runs containing D-mannose, 4-O-beta-galactosyl-mannoside or mannan revealed a significant reduction in the inhibitory effect. Finally, the MLIF activity was virtually absorbed out with mannan-coupled Sepharose 4B beads. This suggests that D-mannose constitutes an essential part of the receptor for MLIF on the human monocyte membrane.

Animals↗
PubMed1991

Increased frequency of HLA-DR3 and complotype SC01 in Mexican mestizo patients with amoebic abscess of the liver.

Our preliminary study (31 patients) of HLA frequencies and amoebic abscess of the liver (AAL) in Mexican mestizos was extended to include 110 patients with this condition. The previously found increase in HLA-B16 was not confirmed, but the frequency of HLA-DR3 was again found significantly increased in patients with AAL when compared to the normal, ethnically matched control population, both in its isolated (35.5% vs 12.7%) and in the HLA-A2, DR3 haplotypic version (20.9% vs 4.5%). Moreover, seven of the 17 HLA specificities that were found to be individually different at P (yet not at PC) level in patients with AAL when compared to the control population, were actually HLA-DR3 containing haplotypes. HLA-DR3 may thus encode a risk factor(s) for AAL, at least in the Mexican mestizo population. Furthermore a significant increase in the complotype SC01 and its haplotypic version SC01, DR4 were identified in 45 non selected patients with AAL when compared to normal controls (31.1% vs 6.7% and 17.8% vs 0% respectively). Even though a relationship between allelic forms of complement components and their function has not been fully established, this complotype could represent a risk factor as well, since complement appears to play a role in host defence against amoebic invasion. Finally, no extended haplotype preference was found in these AAL patients.

Adult↗
PubMed1990

[HLA antigens, complement types, and amebic liver abscess in Mexican mestizos].

The association between parasitic diseases, and antigens of the major histocompatibility complex in man (HLA) has been poorly studied. The only study of the association between the HLA system and amebic abscess of the liver was performed by our group, and revealed a significant increase in HLA-BI6 and HLA-DR3 in patients with amebic abscess of the liver. The present study covered a larger number of patients and controls (110 of each) and it confirmed the association with HLA-DR3, it failed to confirm the association with HLA-BI6.

Adult↗
PubMed1990

[Histocompatibility antigens and acute vascular purpura].

INTRODUCTION: Some kidney diseases are associated to HLA antigens. Nyulassy found an increase in HLA-B35 in patients with Henoch-Schönlein's purpura suffering nephritis (HSP-N). Our study searched for associations of HLA antigens and anaphylactoid purpura nephritis in Mexican mestizo patients. MATERIAL AND METHODS: HLA-A,B, and C antigens were detected by two-step microcytotoxicity in 22 patients with HSP-N and compared to those of 665 healthy subjects of the same ethnic background. RESULTS: A significant association was found between HSP-N and HLA-Aw19 single (pc less than 0.05) or in haplotype form (Aw19-B35) (pc less than 0.005). HLA B35 alone was associated to HSP-N but only at non corrected level (pc less than 0.05). DISCUSSION: The significant association between HLA-Aw19 and Aw19-B35 and HSP-N may indicate a risk factor in Mexican mestizo patients to develop this case.

Adolescent↗
PubMed1987

HLA antigens associated to amoebic abscess of the liver in Mexican mestizos.

Worldwide prevalence of amoebiasis is estimated at 4 x 10(8) cases/year, yet only one of about 300 individuals harbouring Entamoeba histolytica suffers tissue invasion and these cases are mostly concentrated in certain areas of Asia, Africa and Latin America. Patients with amoebic abscess of the liver (AAL) represent only a small fraction of that. These contrasting figures have been tentatively explained on the one hand through variations in sex, immunocompetence, nutritional and other socioeconomic features of the host, and on the other hand through differences in parasite virulence. In order to explore a possible association between the major histocompatibility complex (MHC) and AAL susceptibility, we studied the HLA profile in 31 Mexican mestizos with AAL and compared it to race and socioeconomically matched controls. Mexican mestizo patients with AAL revealed a significant increase in HLA-Bw16 and HLA-DR3 which could suggest an HLA-related susceptibility to liver invasion by E. histolytica.

Abscess↗
PubMed1985

Inhibition of human monocyte locomotion by products of axenically grown E. histolytica.

The supernatant fluid of axenically grown E. histolytica inhibits chemotaxis, chemokinesis and random mobility of human mononuclear phagocytes (MP) as measured in Boyden chambers. Human polymorphonuclear phagocytes (PMN) locomotion is apparently unaffected. The factor was found in comparable amounts in the supernatant fluid of axenic cultures of four E. histolytica strains that differed in their human pathogenicity and virulence, as well as in two entamoebas non-pathogenic for man. This dialysable and thermolabile MP-locomotion inhibiting entamoeba product (EP) can be absorbed out by incubation with MP, but not with lymphocytes, while partial absorption was observed using PMN. The MP-locomotion inhibitory effect of this EP was cancelled by inhibiting protein synthesis in the MP by means of cycloheximide. In vivo, this EP caused a delay in MP migration in Rebuck skin windows. The molecular weight of this EP lies between 478 and 765 by gel-sieve chromatography. Our results suggest a direct effect upon the cytoskeletal and locomotive apparatus of the MP. This MP-locomotion inhibiting EP could contribute to the paucity of the inflammatory reaction observed in the advanced stages of invasive amoebiasis and consequently also to the lack of scar tissue formation upon healing of amoebic lesions.

Adult↗
PubMed1984

HLA-B27 and ankylosing spondylitis in the Mexican Mestizo population.

Two previous surveys of ankylosing spondylitis (AS) in Mexican Mestizos found HLA-B27 frequencies of 68.6% and 78% and a relative risk (RR) of 37.05 and 120.88, respectively. We examined an additional group of Mexican Mestizos with AS and found an HLA-B27 frequency of 80.77% and a RR of 99.24. Our results are statistically comparable to the previous studies, and they suggest that the Mexican Mestizo is similar to the Spaniard in regards to AS and HLA-B27 association.

Female↗
PubMed1981

HLA profile of the Mexican Mestizo population.

The HLA-A, B and C profile of 665 Mexican Mestizos was studied by microcytotoxicity testing for 30 HLA specificities. Antigen, gene and haplotype frequencies were calculated, and results were compared to those of the three other series of HLA profiles in Mexican Mestizos available in the literature: one from Mexico-City, one from Los Angeles, California, USA, and a recent one from San Antonio, Texas, USA. Comparing the antigen frequencies of our series with those of the other study from Mexico-City, significant differences were only found in three antigens of the HLA-B locus. On the other hand, comparison of either series from Mexico-city with the Los Angeles or the San Antonio studies yielded discrepancies in several specificities of both HLA-A and B loci, most notably the consistent absence of A25 in Mexican Mestizos living in Mexico-City. The presence of this specificity in the Mexican Mestizo Population living in these two American cities could have resulted from input of Caucasian and Black genes over several generations. Differences in haplotype frequency were observed comparing the two series from Mexico-City and the series from San Antonio. Comparison of haplotype frequency with the Los Angeles series was not possible.

Ethnicity↗
PubMed1975

[Phagocytosis in patients with splenectomy].

Phagocytosis was evaluated in nine patients with splenctomy undergoing renal transplant, eight renal transplanted patients without splenectomy, three immunodepressed patients with terminal renal failure, four patients with splenectomy and six healthy volunteers. For phagocytosis evaluation, neutrophils adhered to glass were used. They were cover with 4% latex and albumin containing culture medium with or without phagocytosis stimulating tetrapeptide extracted from IgG in each case. Phagocytosis was decreased in all groups studied. Immunodepressed patients showed the highest diminishment of phagocytosis and patients with splenectomy and immunodepression the lesser. It was speculated that such a finding is due to a decrease of tetrapeptide in serum.

Acute Kidney Injury↗
PubMedDate not supplied

Thyrotoxic periodic paralysis in Mexican mestizo patients: a clinical, biochemical and HLA-serological study.

BACKGROUND: Thyrotoxic periodic paralysis (TPP) is characterized by episodes of neuromuscular weakness occurring in the context of hypokalemia and hyperthyroidism and has been predominantly described in Oriental populations. Whereas it is uncommon in Caucasians and Blacks, TPP does occur in individuals of Native American descent. The objective was to analyze the clinical, biochemical, and HLA characteristics of a group of Mexican mestizo patients with TPP. METHODS: The sample was comprised of 14 men with TPP diagnosed since January 1990, based on one or more episodes of flaccid paralysis, accompanied by hypokalemia and occurring in the context of clinical and biochemical hyperthyroidism. Eight were available for HLA testing. RESULTS: Hyperthyroidism was diagnosed before the development of periodic paralysis in five of the patients, whereas in six it occurred afterward. The severity of paralysis did not correlate with the degree of either hypokalemia or hyperthyroidism. An increased frequency of HLA-DR3 was found in Graves' patients without paralysis but not in those with paralysis, as compared to the general population. CONCLUSIONS: TPP is more common than previously thought in Mexicans, in whom it behaves as in other Native American groups. The lack of HLA-DR3 association in Graves' patients with TPP is interesting, but at the moment has no pathophysiological implications.

Adult↗