Biomedical subjects

C Acosta

Publications and source records attributed to C Acosta.

At least 19 recordsLinked to original sources

PubMed2001

[Arterialization of the distal veins of the foot for limb salvage in arteritis. Techniques and results].

STUDY AIM: The aim of this retrospective study was to report the long term results with arterialisation of the veins of the foot as the final attempt to save an ischaemic limb when classical techniques have proved ineffective or impossible. PATIENTS AND METHOD: From January 1974 to July 2000, 60 arterialisations of the distal veins of the foot were performed in 59 patients with arteritis, associated in 25 of them with diabetes mellitus. There were 41 men and 18 women, their mean age was 72 years (range from 49 to 95 years). There were 50 stage IV patients and 9 stage III patients. The arterialisation was performed by a reversed venous bypass between the femoral or popliteal artery and an internal vein of the foot, after destruction of the valvulas of the forefoot veins. The distal anastomosis was made termino lateral in order to provide tissular nutrition and to avoid blood congestion. RESULTS: The result was considered good when a major amputation was avoided during one year at least, with a bypass permeability longer than one month. Among the 60 arterialisations, 36 were successful (60%), 7 in the short term (between one month and one year), 15 in the medium term (between one and five years), 14 in the long term (more than 5 years). Among the 15 medium-term good results, the mean time of bypass permeability was one year; three patients died, six were lost of follow-up, and six were still alive, four of them with a permeable bypass, at the time of the study. Among the 14 long term results, spontaneous bypass occlusion occurred after a 26-month mean time; despite this occlusion, the favourable result persisted till the death of the patient after a mean delay of 9 years (range from 5 to 15 years). The 24 other patients had a poor result followed by a major amputation. There were no deaths in relation with the reversed circulation. CONCLUSION: These results suggest that the arterialisation of the distal veins of the foot may be considered a useful revascularization technique for limb salvage when all the classical methods have failed or are impossible.

Aged↗

PubMed2001

Clinical, surgical, and histopathologic characteristics of corneal keloid.

PURPOSE: To describe the cause, diagnosis, and management of a case of bilateral corneal keloid. METHODS: We describe a 17-year-old white boy with enlarging nontraumatic bilateral corneal scars whose growth was exacerbated by a superficial keratectomy. The patient underwent a penetrating keratoplasty (PK) in his left eye. Light and electron microscopy of the corneal button were performed. RESULTS: The histopathologic and ultrastructural features of the corneal button were haphazardly arranged collagen fascicles with activated fibroblasts but no inflammatory cells. The clinical outcome was excellent, although there has been continuous growth of the outer margin of the initial lesion not included in the PK. This growth has not affected vision. The unoperated right corneal lesion progressively enlarged during these years. CONCLUSION: A corneal keloid, although unusual, should be suspected in cases of enlarging white glistening avascular corneal scars regardless of a traumatic antecedent. Light and electron microscopy confirmed the diagnosis. Management is by PK when the visual axis is involved and carries an excellent prognosis.

Adolescent↗

PubMed2001

Prenatal risk factors of wheezing at the age of four years in Tanzania.

BACKGROUND: A study was undertaken to assess the interactions between prenatal exposures, early life infections, atopic predisposition, and allergen exposures in the development of wheezing up to the age of 4 years in a tropical region of Africa. METHODS: The study subjects comprised children born at the district hospital in Ifakara, Tanzania during a 1 year period who were participating in a trial of iron supplementation and malaria chemoprophylaxis during the first year of life and followed for up to 4 years. From this group of subjects, 658 (79%) participated in the interview at 18 months and 528 (64%) in a second interview at 4 years. Wheezing was measured with the ISAAC questionnaire. A hospital based inpatient and outpatient surveillance system was set up to document all attendance by study children for any cause, including episodes of clinical malaria and lower respiratory tract infections. Total IgE levels and malaria parasites were measured in maternal and cord blood. Total IgE was also measured at 18 months of age. Indoor environmental levels of Der p I and Fel d I were determined using an enzyme linked immunosorbent assay at the same time as the interview at the age of 18 months. RESULTS: The prevalence of wheezing at 4 years is common in Ifakara (14%, range 13-15%). The presence of malaria parasites in cord blood (odds ratio, OR = 6.84, 95% CI 1.84 to 24.0) and maternal asthma (OR = 8.47, 95% CI 2.72 to 26.2) were positively associated with wheezing at the age of 4 years, and cord blood total IgE was negatively associated (OR = 0.24, 95% CI 0.07 to 0.85) (all p<0.05). Parasitaemia at birth was not related to total IgE levels in cord blood (p=0.6). Clinical episodes of malaria during infancy were not associated with wheezing, and nor were levels of indoor aeroallergens. CONCLUSION: These findings suggest that events occurring during pregnancy may play a role in the future appearance of wheezing, although the results must be interpreted with caution because of the small numbers studied.

Allergens↗

PubMed2000

The association between atopy and asthma in a semirural area of Tanzania (East Africa).

BACKGROUND: Atopy is consistently associated with asthma, except in a study in Africa. We assessed the association between atopy and asthma in women from a semirural area of Tanzania (East Africa). METHODS: All pregnant women delivering at the district hospital during a 1-year period were recruited (n = 658, 60.6% of those selected). Asthma was investigated by a standard questionnaire and atopy by specific IgE (immunoglobulin E) antibodies to Dermatophagoides pteronyssinus (Der p 1) and cockroach. RESULTS: The prevalence of wheezing chest was 10.7%; of asthma, 3.5%. Levels of specific IgE of >0.35 kU/l (73%) and high levels of total IgE (62% higher than 1000 kU/l) were highly prevalent. Specific IgE antibody levels in sera were not associated with asthma (3.8% of women with negative specific IgE to any antigen had asthma in comparison to 4.0% of women with positive specific IgE; odds ratio [OR] = 1.06, 0.35-3.22). Total IgE was not different between women with asthma and women without asthma (P=0.36). CONCLUSIONS: In tropical regions, the association between allergy and asthma is complex, and specific IgE reactivity to environmental allergens may not be related to asthma.

Adolescent↗

PubMed2000

Monoclonal antibodies against hepatitis B s antigen: production, characterization, and use for diagnosis.

Three different hybridoma clones secreting anti-HBsAg antibody were constructed by fusing cells of mouse myeloma line Ag8-X63 with splenocytes from BALB/c mice immunized with recombinant HBsAg and natural HBV. The monoclonal antibodies obtained were characterized immunologically, and two were used to develop UMELISA for detection of HBsAg. This monoclonal assay enabled the detection of 0.1 UPE/mL with reference to the standard of the Paul Ehrlich Institute (Frankfurt, Germany). The assay compared well with a commercially available kit (UMELISA HBsAg) and was used for detection of HBsAg in blood donors.

Animals↗

PubMed2000

Use of nonpreserved human amniotic membrane for the reconstruction of the ocular surface.

PURPOSE: To describe the use of nonpreserved human amniotic membrane (NP-AMT) as an alternative to preserved human amniotic membrane (AMT) for the reconstruction of the ocular surface in several diseases. METHODS: NP-AMT was used in the treatment of five patients with the following diseases: noninvasive conjunctival squamous cell carcinoma, corneal persistent epithelial defect, severe alkali burn, near total limbal deficiency secondary to multiple surgeries, and ocular cicatricial pemphigoid. In some cases, a limbal autograft or allograft was employed simultaneously, sutured on top of the NP-AMT. All sutures were made with 10-0 Nylon and were removed at two weeks. RESULTS: Ocular surface was satisfactorily reconstructed, eyes were quiet, and patients were comfortable despite prolonged deepithelialization in some cases. There was a case of a limbal autograft ischemia--in the burned patient--that caused partial corneal conjunctivalization. Initially, the NP-AMT looks thickened but thins around the fifth day and looks similar to AMT. CONCLUSION: Results using NP-AMT are similar to those of AMT. It is a good alternative and it is easily obtained in places were AMT is not available or is too expensive to procure.

Adult↗

PubMed1999

Prevalence and mother-to-infant transmission of hepatitis viruses B, C, and E in Southern Tanzania.

Hepatitis B and C markers were tested in 980 pregnant women, in the infants born to infected mothers, and in a random sample of 42 and 50, respectively, children born to uninfected mothers in Tanzania. Sixty-two women (6.3%) were positive for HBsAg and 15 (24%) were HBeAg-seropositive. Anti-HCV was detected in 49 women (5%), 15 (31%) of whom had detectable viremia. HCV RNA serum levels were low and only genotype 4 was identified. Sixty-six women (6.7%) were positive for anti-HIV, six of whom were coinfected with HBV and one with HCV. Anti-HEV was negative in the 180 women tested. At 8 months of age, HBsAg was detected in 8% and 2% of children born to HBV-infected and noninfected mothers, respectively (P = 0.2). Corresponding figures at 18 months of age were 31% and 21% (P = 0.3). When tested at 2 months of age, HCV RNA was not detected in any of the 43 children born to anti-HCV-positive mothers nor in any of 50 children born to anti-HCV-negative mothers. At 18 months, only one child, born to an anti-HCV-positive mother, had detectable HCV RNA. None of the infants born to women with HIV coinfection were infected with hepatitis viruses. This study suggests that exposure to HEV does not occur in southern Tanzania. The prevalence of current HBV infection in pregnant women from rural Tanzania is lower than in other sub-Saharan areas. In early childhood, HBV infection appears to occur by horizontal rather than maternofilial mechanisms of transmission. The prevalence of HCV infection is similar to that in other African countries. The results of this study show for the first time in Africa that mother-to-infant transmission does not play a significant role in the acquisition of HCV infection.

Adolescent↗

PubMed1999

African children with malaria in an area of intense Plasmodium falciparum transmission: features on admission to the hospital and risk factors for death.

Malaria remains the most important parasitic cause of mortality in humans. Its presentation is thought to vary according to the intensity of Plasmodium falciparum transmission. However, detailed descriptions of presenting features and risk factors for death are only available from moderate transmission settings. Such descriptions help to improve case management and identify priority research areas. Standardized systematic procedures were used to collect clinical and laboratory data on 6,624 children admitted to hospital over a 1-year period in an intensely malarious part of Tanzania. Frequencies of signs and symptoms were calculated and their association with a fatal outcome was assessed using multivariate logistic regression. There were 72 deaths among 2,432 malaria cases (case fatality rate [CFR] = 3.0%); 44% of the cases and 54% of the deaths were in individuals less than 1 year of age. There was no association between level of parasitemia and CFR. Increased risk of dying was independently found in all children with hypoglycemia (odds ratio [OR] = 6.7, 95% confidence interval [CI] = 3.9-11.7), in children 1-7 months of age with tachypnea (OR = 8.8, 95% CI = 2.6-30.5) and dehydration (OR = 5.0, 95% CI = 1.9-14.2), and in children 8 months to 4 years of age with chest indrawing (OR = 4.7, 95% CI = 2.0-11.2) and inability to localize a painful stimulus (OR = 6.9, 95% CI = 2.9-16.5). Children in the bottom quartile of weight-for-age were more likely to die (OR = 2.1, 95% CI = 1.3-3.5). Eight percent of the malaria cases had severe anemia (packed cell volume < 15%) but 24% received a blood transfusion. The epidemiology of malaria disease may be more complex than previously thought. Improved case management in a wide variety of health facilities may result from adequate identification and treatment of dehydration and hypoglycemia. Transfusion-requiring anemia is a major problem and sustainable, effective preventive measures are urgently needed.

Adolescent↗

PubMed1992