DOT-ELISA for detection of anti-Cysticercus cellulosae antibodies in human cerebrospinal fluid using a new solid-phase (resin-treated polyester fabrics): preliminary report

A dot enzyme-linked immunosorbent assay (DOT-ELISA) was developed to detect specific antibodies in cerebrospinal fluid (CSF) for human neurocysticercosis immunodiagnosis, with Cysticercus cellulosae antigen dotted on a new solid-phase. This was represented by sheets of a synthetic polyester fabric impregnated with a polymerized resin (N-methylol-acrylamide). A very stable preparation was thus obtained, the antigen being covalently bound by cross-linking with free N-methylol groups on the resin. Since robust, no special care was necessary for handling the solid-phase. The test could be performed at room-temperature. From 30 CSF samples assayed, 14 were positive, from a group of 15 cases of neurocysticercosis, with titers from 1 to 128; 15 other samples, from normals or other neurological diseases, were all negative. Test characteristics seem to indicate it as adequate for epidemiological surveys. A more detailed study on sensitivity, specificity, reproducibility and the use in serum samples is being conducted.

Dot-ELISA-IgM in saliva for the diagnosis of human leptospirosis using polyester fabric-resin as support (Preliminary Report)

In order to improve the diagnosis of human leptospirosis, we standardized the dot-ELISA for the search of specific IgM antibodies in saliva. Saliva and serum samples were collected simultaneously from 20 patients with the icterohemorrhagic form of the disease, from 10 patients with other pathologies and from 5 negative controls. Leptospires of serovars icterohaemorrhagiae, canicola, hebdomadis, brasiliensis and cynopteri grown in EMJH medium and mixed together in equal volumes, were used as antigen at individual protein concentration of 0.2 µg/µl. In the solid phase of the test we used polyester fabric impregnated with N-methylolacrylamide resin. The antigen volume for each test was 1µl, the saliva volume was 8 µl, and the volume of peroxidase-labelled anti-human IgM conjugate was 30 µl. A visual reading was taken after development in freshly prepared chromogen solution. In contrast to the classic nitrocellulose membrane support, the fabric support is easy to obtain and to handle. Saliva can be collected directly onto the support, a fact that facilitates the method and reduces the expenses and risks related to blood processing.

Dot-ELISA for the detection of anti-Cysticercus cellulosae antibodies in cerebrospinal fluid using a new solid phase (resin-treated polyester fabric) and Cysticercus longicollis antigens

A dot-ELISA was developed for the detection of antibodies in CSF in the immunologic diagnosis of human neurocysticercosis, using antigen extracts of the membrane and scolex of Cysticercus cellulosae (M+S-Cc) and, alternately, membrane (M) and vesicular fluid (VF) of Cysticercus longicollis (Cl) covalently bound to a new solid phase consisting of polyester fabric treated with N-methylol-acrylamide resin (dot-RT). The test was performed at room temperature, with reduced incubation times and with no need for special care in the manipulation of the support. The sensitivity rates obtained were 95.1% for antigen Cc and 97.6% for antigen Cl. Specificity was 90.6% when Cc was used, and 96.9% and 100% when M-Cl and VF-Cl were used, respectively. No significant differences in titer were observed between tests carried out with homologous and heterologous antigens. The low cost and easy execution of the dot-RT test using antigen extracts of Cysticercus longicollis indicate the test for use in the immunodiagnosis of human neurocysticercosis.

Percutaneous closure of ductus arteriosus with the amplatzer prosthesis. The Brazilian experience

OBJECTIVE - To report the results of percutaneous occlusion of persistent ductus arteriosus with the Amplatzer prosthesis in 2 Brazilian cardiological centers. METHODS - From May 1998 to July 2000, 33 patients with clinical and laboratory diagnosis of persistent ductus arteriosus underwent attempts at percutaneous implantation of the Amplatzer prosthesis. The median age was 36 months (from 6 months to 38 years), and the median weight was 14kg (from 6 to 92kg). Sixteen patients (48.5%) were under 2 years of age at the time of the procedure. All patients were followed up with periodical clinical and echocardiographic evaluations to assess the presence and degree of residual shunt and possible complications, such as pseudocoarctation of the aorta and left pulmonary artery stenosis. RESULTS - The minimum diameter of the arterial ducts ranged from 2.5 to 7.0mm (mean of 4.0±1.0, median of 3.9). The rate of success for implantation of the prosthesis was 100%. Femoral pulse was lost in 1 patient. The echocardiogram revealed total closure prior to hospital discharge in 30 patients, and in the follow-up visit 3 months later in the 3 remaining patients. The mean follow-up duration was 6.4±3.4 months. All patients were clinically well, asymptomatic, and did not need medication. No patient had narrowing of the left pulmonary artery or of the aorta. No early or late embolic events occurred, nor did infectious endarteritis. A new hospital admission was not required for any patient. CONCLUSION - The Amplatzer prosthesis for persistent ductus arteriosus is safe and highly effective for occlusion of ductus arteriosus of varied diameters, including large ones in small symptomatic infants.

Fibrinolytic therapy for thrombosis in cardiac valvular prosthesis short and long term results

OBJECTIVE: To assess the short- and long-term results of the use of streptokinase (SK) for the treatment of thromboses in cardiac valvular prostheses. METHODS: Seventeen patients with cardiac prosthetic thrombosis diagnosed by clinical, echocardiographic, and radioscopic findings underwent fibrinolytic treatment with a streptokinase bolus of 250,000 U followed by 100.000 U/hour. Short- and long-term results were assessed by radioscopy and echocardiography. RESULTS: Of the 17 patients, 12 had mechanical double-disk prostheses (4 aortic, 6 mitral, 2 tricuspid), 4 had single-disk prostheses (2 aortic, 1 mitral, and 1 tricuspid), and 1 had a tricuspid bioprosthesis. The success rate was 64.8%, the partial success rate was 17.6%, and the nonsuccess rate was 17.6%. All patients with a double-disk prosthesis responded, completely or partially, to the treatment. None of the patients with a single-disk prosthesis had complete resolution of the thrombosis. The time of streptokinase infusion ranged from 6 to 80 hours (mean of 56 h). The mortality rate due to the use of streptokinase was 5.8% and was secondary to cerebral bleeding. During streptokinase infusion, 3 (17.6%) embolic episodes occurred as follows: 1 cerebral, 1 peripheral, and 1 coronary. The rethrombosis index was 33% in a mean follow-up of 42 months. CONCLUSION: The use of fibrinolytic agents was effective and relatively safe in patients with primary thrombosis of a double-disk prosthesis. A fatal hemorrhagic complication occurred in 1 (5.8%) patient, and embolic complications occurred in 3 (17.6%) patients. In a mean 42-month follow-up, 67% of the patients were free from rethrombosis.

Immunization by subcutaneous implants of polyester-polyurethane sponges coupled with antigen

A new protocol is described for immunization of outbred Swiss mice. The procedure is based on subcutaneous implantation of antigen-coupled polyester-polyurethane sponges cut into disks of 10 mm in diameter vs 2 mm in thickness. Antigen coupling was performed by overnight incubation of the sponge with a solution of ovalbumin (Ova) (2 mg/ml) diluted in sodium carbonate buffer, pH 9.6. The amount of ovalbumin that was taken up by the sponge was between 71.4 to 82.5 µg. This was estimated by comparing the Ova absorbance at 280 nm in coating buffer solutions before and after incubation. To compare the efficiency of the proposed method, experimental groups immunized with the antigen in the presence of adjuvants (10 µg in Al(OH)3 or 100 µg in complete Freund's adjuvant (CFA)) were run in parallel. The data obtained after the 3rd week of immunization indicate that both cellular and humoral immune responses were achieved. These were assayed by antigen-induced footpad swelling and ELISA (specific antibodies), respectively. The levels of both immune responses elicited were similar to the responses observed in mice immunized with ovalbumin in the presence of Al(OH)3. The method might represent an advantage when immunizing with pathogenic antigens. Preliminary experiments have suggested that the antigen remains immobilized or bound to the sponge for a long period of time, since there is an increment on the cell population inside the sponges after boosting the animals. If so, the undesirable effects of immunization would be reduced.

Construction of 2D transparent micromodels in polyester resin with porosity similar to carrots

Microscopic visualization, especially in transparent micromodels, can provide valuable information to understand the transport phenomena at pore scale in different process occurring in porous materials (food, timber, soils, etc.). Micromodels studies focus mainly on the observation of multi-phase flow, which presents a greater proximity to reality. The aim of this study was to study the process of flexography and its application in the manufacture of polyester resin transparent micromodels and its application to carrots. Materials used to implement a flexo station for micromodels construction were thermoregulated water bath, exposure chamber to UV light, photosensitive substance (photopolymer), RTV silicone polyester resin, and glass plates. In this paper, data on size distribution of a particular kind of carrot we used, and a transparent micromodel with square cross-section as well as a Log-normal pore size distribution with pore radii ranging from 10 to 110 µm (average of 22 µm and micromodel size of 10 × 10 cm) were built. Finally, it stresses that it has successfully implemented the protocol processing 2D polyester resin transparent micromodels.

Evaluation of polymethylmethacrylate as ocular implant in rabbits subjected to evisceration

Spheres of different types of material are used for the replacement of lost volume after removal of the eye bulb or its content to prevent contraction of the orbital cavity. The aim of this study was to evaluate the scope of polymethylmethacrylate (PMMA) used as intraocular implant in eviscerated rabbit eye. Twelve New Zealand rabbits underwent unilateral evisceration of the left eye, with subsequent implantation of PMMA sphere 12 mm in diameter. Clinical evaluation was performed daily during the first 15 days after surgery and every 15 days until the end of the study period (180 days). For the histopathological analysis, three animals per trial underwent enucleation at 15, 45, 90 and 180 days after evisceration. There was no wound dehiscence, signs of infection or implant extrusion in any animal throughout the study period. Histological examination revealed the formation of fibrovascular tissue around the implants. The PMMA behaved as inert and non-integrable.

Oral health, hygiene practices and oral cancer

OBJECTIVE: To assess the association between oral health and hygiene practices and oral cancer. METHODS: Hospital-based case-control study in the metropolitan area of São Paulo, southeastern Brazil, from 1998 to 2002. A total 309 patients with squamous cell carcinoma of the mouth and the pharynx and 468 controls matched by sex and age were included in the study. Cases were recruited in seven reference hospitals and controls were selected in five out of the seven participating hospitals. Detailed information on smoking, alcohol consumption, schooling, oral health status and hygiene practices were obtained through interviews. Odds ratios (OR) and 95% confidence intervals (95% CI), adjusted by sex, age, schooling, smoking, alcohol consumption as well as the variables oral health status and hygiene practices were estimated using unconditional logistic regression analyses. RESULTS: The use of complete dental prosthesis was not associated with oral cancer but regular gum bleeding showed a strong association (OR 3.1; 95% CI 1.2-7.9). Those who never attended a dental visit were more likely to have oral cancer (OR 2.5; 95% CI 1.3-4.8). Daily mouthwash use showed a stronger association to pharynx (OR 4.7; 95% CI 1.8-12.5) than mouth cancer (OR 3.2; 95% CI 1.6-6.3). CONCLUSIONS: Gum bleeding, no dental care, and daily mouthwash use were factors associated with oral cancer regardless of tobacco and alcohol consumption.

Activity of Tri-N-Butyl Tin maleate in carpets against Staphylococcus aureus and Aspergillus niger, verified through two methodologies: Inhibition Halo (HZ) and Inhibition Surface (Print)

The aim of the present study was to verify the activity of the Tri-N-Butyl Tin maleate compound against Staphylococcus aureus and Aspergillus niger, after its industrial application in 40 samples of carpets of different materials (polypropylene, polyester, polyamide and wool). The qualitative assays were performed through two methodologies: Inhibition Halo (HZ) and Inhibition of Surface (Print). The carpet with the product inhibited 100% of bacterial (Staphylococcus aureus) and fungi (Aspergillus niger) growth, under the conditions of this study. The microbial inhibition was higher in upper portion of carpets. The methodologies employed appear to be adequate to test the bactericide and fungicide activities of the Tri-N-Butyl Tin maleate. The print methodology confirmed the results obtained by the inhibition zone assay. Further studies using the same methodologies are needed to confirm our results.

FACTORS RELATED TO ORAL CANDIDIASIS IN ELDERLY USERS AND NON-USERS OF REMOVABLE DENTAL PROSTHESES

This study examined the association between oral candidiasis in elderly users and nonusers of prosthesis and its predisposing factors. To this end, we performed a cross-sectional study where saliva samples from 48 patients were collected they used prosthesis and 43 patients (control group) who did not use. Among the 91 patients, Candida spp were isolated in 40 (83.3%) who used prosthesis and in 23 (53.5%) in the control group. A statistically significant association was determined between the two groups, the isolation of yeasts and dental prosthesis (p < 0.05, OR = 4.3). The most common etiological agent was Candida albicans (37 isolates), with 23 (62.2%) in the denture group and 14 (37.8%) (control group). Among patients who presented clinical manifestations of oral candidiasis (n = 24), 83.3% (n = 20) belonged to the group that wore dentures, while only 16.7% (n = 4) belonged to the control group. Elderly patients with diabetes had 4.4 times higher estimated risk of developing oral candidiasis when compared with individuals without this condition. There was no statistically significant association between being user prostheses and have diabetes with the onset of candidiasis. No statistically significant association was determined between xerostomia, use of prosthesis and oral candidiasis. The use of prosthetics and poor oral hygiene in elderly patients predisposes to the development of oral candidiasis.

Invasive aspergillosis in a user of inhaled cocaine: rhinosinusitis with bone and cartilage destruction

Aspergillosis is an infection caused by saprophytic fungi of the genus Aspergillus, which typically occurs in immunosuppressed individuals, but has also been reported in immunocompetent patients. The main routes of entry are the respiratory tract, skin, cornea, and ear, and the infection may be localized or disseminated by contiguity or vascular invasion. We report a severe case of rhinosinusitis with cutaneous involvement, caused by invasive aspergillosis, in an immunocompetent user of inhaled cocaine. Invasive aspergillosis related to cocaine abuse has not yet been reported in the literature. After itraconazole treatment and surgical debridement, complete clinical remission was achieved. Nasal reconstruction with a skin graft over a silicone prosthesis resulted in a satisfactory esthetic outcome.

The use of bone bridges in transtibial amputations

We sought to describe the bone bridge technique in adults, and present a variation for use in children, as well as to present its applicability as an option in elective transtibial amputations. This paper presents a prospective study of 15 transtibial amputations performed between 1992 and 1995 in which the bone bridge technique was employed. The patients' ages ranged from 8 to 48 years, with an average of 22.5 years. This technique consisted of the preparation of a cylinder of periosteum extracted from the tibia and with cortical bone fragments attached to it to promote a tibiofibular synostosis on the distal extremity of the amputation stump. We noted that the cortical bone fragments were dispensable when the technique was employed in children, due to the increased osteogenic capacity of the periosteum. This led to a variation of the original technique, a bone bridge without the use of the cortical bone fragments. RESULTS: The average time spent with this procedure, without any significant variation between adults and children, was 171 minutes. The adaptation to the definitive prosthesis was accomplished between 20 and 576 days, with an average of 180 days. Revision of the procedure was necessary in 3 amputations. CONCLUSIONS: This technique may be employed in transtibial amputations in which the final length of the stump lies next to the musculotendinous transition of the gastrocnemius muscle, as well as in the revision of amputation stumps in children, where the procedure has been shown to be effective in the prevention of lesions due to excessive bone growth.