Synthesis and antiprotozoan properties of new 3,5-disubstituted-tetrahydro-2H-1,3,5-thiadiazine-2-thione derivatives

In a search for antiprotozoan compounds, 34 new 3,5-disubstituted-tetrahydro-2H-1,3,5-thiadiazine-2-thione derivatives were synthesized and tested in vitro against Trypanosoma cruzi and Trichomonas vaginalis. Some of them showed important antiprotozoan activity. In vivo assays of compounds which showed remarkable in vitro activity against T. vaginalis were carried out.

Broad band spectral EEG parameters correlated with different IQ measurements

The relationship of IQ (measured by WAIS and all its subscales) and EEG broad band spectral parameters were studied in 40 right-handed, male volunteers ranging in age from 20 to 25 years old. EEGs were recorded in 20 derivations during rest with eyes opened. The results obtained reveal positive and negative correlations with abundant frontal participation in all bands. Mean frequency data show a frequency shift in a very narrow range suggesting that more relations in narrow band could be achieved. These results highlight the need of psychological tests that measure more homogeneous abilities and finer measurement technique to reveal clearly explainable correlations and demonstrate that EEG recordings do reflect intellectual abilities.

[Automatic, implantible cardioverter-defibrillator in a patient with chronic Chagas cardiopathy and sustained ventricular tachycardia]

We studied a 48 years old woman, with chronic Chagasic cardiopathy, manifested with cardiomegaly, heart failure and syncope, due to a sustained ventricular tachycardia (SVT) of two different configurations (left bundle branch block and right bundle branch block). During electrophysiological testing, both types of ventricular tachycardia were reproduced. Successful ablation therapy of the right branch of His was performed due to suspicion of the bundle branch reentrant tachycardia, with a left bundle branch block. The patient continued to show SVT episodes, now with right bundle branch block pattern. Cardioverter Defibrillator was implanted. We report this case due to the rare frequency of Chagas' disease, where it could be a cause of heart disease, since the existence of the parasite (trypanosoma cruzi) and its vector (Triatoma) has been identified in some rural and suburban zones in the state of Aguascalientes, Mexico.

[Evaluation of a mouse anti-IgG-fluorescein conjugate using indirect immunofluorescence and flow cytometry techniques]

An immunoglobulin G of mouse was purified from sera by affinity chromatography in protein A. The rabbits whose sera were able to recognize the antigen injected by double immunodiffusion were immunized with this preparation. The antibodies were precipitated from the rabbit's serum and purified by ion exchange chromatography. This preparation was conjugated to fluorescin isothiocyanate according to the conventional technique. The conjugated obtained was evaluated with the reference strains of Parainfluenza virus 1, 2, 3; Adenovirus; respiratory syncytial virus; and influenza virus A and B, by an indirect immunofluorescence technique and HIV positive samples by flow citometry. Specific monoclonal antibodies were used in both cases. Clinical specimens of patients with acute respiratory infection were evaluated.

[World-wide eradication of smallpox]

A short history of the disease and its vaccination is described. The role of WHO and its country members is underlined, in this unique triumph of the history of medicine. The success of the implementation of the programme and its monitoring of the epidemiological situation of the disease to the final declaration of the WHO 1980, of smallpox eradication, are analyzed.

Thyroid abscess due to Rhodococcus equi in a patient infected with the human immunodeficiency virus

A case of thyroid abscess due to Rhodococcus equi in an HIV-positive patient with previous pulmonary abscess is reported. Rhodococcus equi is a gram-positive rod that can cause infections in both immunocompetent and immunocompromised patients, though it occurs more frequently in patients with dysfunctional cellular immune systems. Several cases of Rhodococcus equi infection in persons infected with HIV have been reported. In these patients Rhodococcus equi usually invades the lungs, producing pneumonia. These infections often relapse, accompanied by intermittent bacteremia, despite conventional treatment. Extrapulmonary abscesses can occur.

Quantitative ELISA for mouse monoclonal antibody determination in culture supernatants and in human serum

An ELISA has been set up for quantifying mouse monoclonal antibodies in culture supernatant. The assay includes rabbit anti-mouse IgG antibodies chromatographycally purified. This preparation was used as coating and as conjugated antibodies in the ELISA. The assay can detect IgG1 with sensitivity of 0.2 ng/mL, IgG2a (0.85 ng/mL), IgG2b (0.13 ng/mL), and IgG3 (3.19 ng/mL) in culture supernatants. The effective working range was from subnanogram per mL quantities to 30 ng/mL by using a computer statistical program. Variation coefficient of ELISA was below 7%. Correlation estimates with a similar ELISA using commercial reagents were performed for each mouse antibody subclass. The assay was able to detect the four mouse monoclonal antibody subclasses in pure human serum as compared with the same ELISA using commercial antibodies. A 24-h pharmacokinetic profile of 1 patient treated with an IgG2a monoclonal antibody is presented.

[Radiofrequency ablation of type I atrial flutter: combination of electrophysiological and anatomical techniques]

Atrial flutter type I (FLA) is one of the most common arrhythmias found in clinical practice. Reentry into the right atrium (AD) is the mechanism of this arrhythmia. The reentry mechanism has critical sites where radiofrequency (RF) can act blocking the circuit. Both, electrophysiological and anatomical approaches using RF to FLA have demonstrated a success rate above 80%. Our group combined both techniques treating 35 patients with FLA type I (22 men and 13 women), with mean age of 40.8 +/- 15 years old (range 9-70). In 21 patients (60%) this arrhythmia was associated with cardiopathy. All patients had failed to respond to different antiarrhythmic therapy. The success rate was 82.8% (29/35). When compared failure vs success we observed that patients who failed were older (51.8 vs 38.5 years old, p < 0.05), had structural cardiopathy (83.3% vs 55.1%, p = NS), had FLA type I with P waves with shorter cycle length (195 vs 254 ms, p = 0.052), had the arrhythmia chronically (129.6 vs 68.1 month, p = NS), had great left atrium diameter (41.2 vs 36.7 mm, p = 0.052) and frequently had been associated with atrial fibrillation (33.3% vs 3.4%, p = 0.02). There were no complications. Six (20.6%) patients reverted to FLA. We followed our patients during mean time 8.37 +/- 8.8 months (1-36). Our results support the notion that FLA type I can be treated with high percentage of success and low risk of complications when both RF techniques are combined. Our predictors of failure were: gender and associated atrial fibrillation (p < 0.05). We conclude that RF is the treatment of choice in every patient with FLA type I who had failed to antiarrhythmic therapy. We recommend RF as soon as FLA has been diagnosed because the probability of success is higher in such instances.

Monoclonal antibodies raised to the dengue-2 virus (Cuban: A15 strain) which recognize viral structural proteins

Mouse monoclonal antibodies (MAbs) were raised to dengue-2 virus (D-2V) Cuban (A15) strain and the cell culture supernatants were screened by ELISA using the homologous virus. Three MAb-secreting lines were further characterized using immunoblot, haemaglutination, complement-fixation, and neutralization assays. One of these, MAb 8H8, weakly reacted with the viral nonstructural-1 protein (NS1) but more specifically identified the capsid protein (C), MAb 3E1 recognized in serological assays D-2V A15 but it had a weak reaction to C protein by immunodetection whereas another, MAb 4G3, weakly neutralized the homologous virus isolate and blocked the binding of specific anti-envelope (E) Mab, and its reaction with this protein could not be confirmed using immunoblot assays. These reagents are now being used to compare virulent plus avirulent Caribbean viruses antibody dependent enhancement (ADE) assays.

[Astrocytomas in pediatrics. The prognostic factors and survival]

Tumors of the central nervous system are the second most frequent malignancy in children under the age of 15 the majority of which are astrocytomas. The purpose of this paper is to analyze the effect of some factors on the survival of patients with astrocytomas. We reviewed the clinical charts of patients with a diagnosis of astrocytoma from 1984 to 1995 and we analyzed the age, sex, location, malignant grade and survival according to the actuarial method and log rank tests. A total of 39 patients were detected, 43% were supratentorial, 13% cerebellar and 43% from the brain stem. There was a better prognosis for those located supratentorial or cerebellar with respect to those in the brain stem, with statistical significance. The treatment consisted in surgical resection in 26 patients, 17 of which were found to have a high grade of malignancy and 9 with low grade, with statistically better prognosis for low grade tumors. There were 17 deaths during the period, with 8 of these patients having a high grade tumor a 10, with brain stem tumors. Forty-one percent of the patients that died did so in the first year and 94% during the first two years after diagnosis. Patients with cerebellar astrocytoma and patients with low-grade astrocytomas had the best prognosis.

A follow-up study of EEG coherences in children with different pedagogical evaluations

A follow-up study on EEG coherence values was carried out with 46 school-age children divided into three pedagogical groups considering their reading and writing abilities (normal subject and children with mild and with serious reading-writing problems). EEGs were recorded at rest, with eyes closed in 15 referential derivations that gave 105 possible coherence values. Coherence was calculated after the elimination of the average reference. Repeated Measure ANOVAs were calculated to evaluate the effects of time, sex, reading-writing problems and their interactions. The second EEG recordings were taken 2-3 years after the first. The results revealed significant increase of coherence values during the time lapse studied, consisting of an increase of frontal coherences in all bands, with the exception of the theta band. The most numerous changes occurred in the alpha band. Very few differences in coherence values were observed between the two EEG recordings by pedagogical groups and by sex suggesting a similar but not igual maturation of coherences of boys and girls and of the three pedagogical groups, in this age range studied. These findings suggests an abnormal coherence development for the reading disabled group, as well as different coherence maturation for boys and girls in this time lapse studied.

[Performance of the IgG avidity test in patients with cytomegalovirus disease]

BACKGROUND

IgG antibodies produced early in infection has a low avidity to their respective epitopes, so that an assay to detect those antibodies could be easily used to diagnose a recent primary infection. A prospective study of anti-CMV IgG avidity test in patients with microbiological evidence of active CMV infection was made.

METHODS

One hundred thirty-five patients were studied. All patients sera were tested for CMV antibodies "pool" IgG/IgM, IgM and antibody IgG avidity index (AI). Furthermore, samples of blood leucocytes from immunosuppressed patients to detect CMV viremia by conventional and shell-vial cell culture isolation and to detect CMV antigenemia, were processed. The avidity index IgG-CMV (AI IgG-CMV) less than 60% was defined as a positive result. CMV infection and disease were defined.

RESULTS

The avidity index was < 60% in 16.3% of all patients and in 68.7% of patients with CMV disease. AI IgG-CMV was positive in 81.8% of patients with primary CMV disease and 9.1% with secondary CMV disease. The mean avidity index reading was 35% in primary CMV disease, 88.3% in secondary CMV disease (p < 0.001) and 87.9% in infected patients without CMV disease criterion (p < 0.001). The sensitivity, specificity, VPP and VPN of avidity index IgG-CMV were 85.7%, 97.4%, 75.0% and 94.9% respectively, in primary CMV disease diagnostic respect to all patients with microbiological evidence of active CMV infection.

CONCLUSIONS

Avidity index IgG-CMV seems to be a good serological test to diagnose primary CMV disease with only one serum, probably with independence of patients immune state.

Use of interferon-alpha in laryngeal papillomatosis: eight years of the Cuban national programme

Laryngeal papillomatosis is one of the first diseases where interferon (IFN) was found to be effective. In 1983, a programme for the treatment of all such cases started in Cuba. Up to December 1991, 125 patients (92 children, 33 adults) have been treated: 102 with leucocyte IFN-alpha, 12 with recombinant IFN-alpha-2b, and 11 have received both preparations. Case management consisted of surgical removal of the lesions followed by an IFN schedule starting with 10(5) IU/kg of weight in children or 6 x 10(6) IU in adults, i.m. daily. The dose was progressively reduced, as long as no relapses occurred. At the end of the one-year schedule the doses were reduced to 5 x 10(4) IU/kg in children or 3 x 10(6) IU in adults, weekly. If there was a relapse, it was removed surgically and the patient returned to a higher dose level. Most cases (89; 71 per cent) have not relapsed after the treatment; 60 of them have been followed for more than three years. In those with relapses, the frequency of recurrence decreased in all but four patients. The treatment seemed to be more effective if initiated less than three months after the disease onset. The tracheostomy could be removed in five out of seven patients who needed it before the IFN treatment and was necessary in only three new cases during IFN treatment. In two of these, decannulation was possible later on. In a total of 14 patients relapses persisted after several cycles of IFN treatment. They were considered resistant to such treatment. No severe side effects were reported. The most frequent ones were fever, drowsiness, increased bronchial secretion, chills and headache. The establishment of this programme has maintained the disease under control in Cuba.

[Microbiological study of vulvovaginitis in premenarcheal girls]

BACKGROUND

A prospective microbiological study of the vaginal swab specimens from premenarcheal girls with clinical diagnosis of vulvovaginitis was done from the 1st of September 1991 to the 31st of August 1994.

PATIENTS AND METHODS

Vaginal secretions from premenarcheal girls with clinical findings were examined. Most important pathogenic agents were investigated and if there was an inflammatory reaction in the Gram stain and a heavy growth on culture, other potentially pathogenic agents were considered also.

RESULTS

In 70 (28.7%) of the 262 patients a potentially pathogenic microorganism was found: eight cases (3.0%) due to Streptococcus pyogenes, four cases (1.5%) due to Candida albicans. Only in one case Neisseria gonorrhoeae was isolated. Among the uncertain etiologic agents, Haemophilus influenzae was the most frequently isolated (7.6%). In 25 (12.6%) of the 198 patients Enterobius vermicularis ova were visualized.

CONCLUSIONS

Streptococcus pyogenes was the most frequently related organism with the vulvovaginitis syndrome among the traditionally established pathogens. The role of Haemophilus influenzae should be considered due to the high prevalence of isolation in this group of patients. We consider that differential diagnosis with Enterobius vermicularis infestation should be done in all cases.

[Disseminated infection by Mycobacterium scrofulaceum: apropos of 3 cases]

BACKGROUND

Mycobacterium avium-M. Intracellulare complex and Mycobacterium kansasii cause most of nontuberculous mycobacteria infections in AIDS patients in Spain. Mycobacterium scrofulaceum is rarely isolated as a cause of disseminated disease and most of case have been reported before the AIDS occurrence.

METHODS

Three clinical cases of patients with disseminated disease caused by M.scrofulaceum and AIDS are reviewed.

RESULTS

Clinical presentation in all cases was similar to those of other disseminated mycobacterial infection, and was also linked to severe immunosuppression (CD4 cell count < 100 CD4/mm3).

CONCLUSIONS

In our area, M. scrofulaceum is the second species of nontuberculous mycobacteria causing disseminated disease in AIDS patients. The most frequent species is M. avium-M. intracellulare complex. For diagnosis an AIDS patient complaining of febrile syndrome without foci and severe immunosuppression, is mandatory to obtain blood cultures and biopsy or adenopathy aspirates if present. To our knowledge, these are the first reports in our country.

Epidemic neuropathy in Cuba: morphological characterization of peripheral nerve lesions in sural nerve biopsies

More than 50,000 patients were affected in Cuba during an epidemic outbreak of peripheral neuropathy from January 1992 until September 1993. The disease presented as either a retrobulbar optic neuropathy, a predominantly sensory peripheral neuropathy, a dorsolateral myeloneuropathy, or as mixed forms. The morphological findings in sural nerve biopsies from 34 patients with various forms of the disease are presented here. Frozen, paraffin and semi-thin sections were prepared for light and electron microscopy, immunohistochemistry and morphometric analysis. Every case presented morphological alterations ranging from mild axonal dystrophy (9 cases, or 27%) to moderate and severe axonal damage (25 cases, or 73%). In 6 cases (18%), axonal damage was accompanied by perineural fibrosis and vascular abnormalities. Axonal regeneration was noted in 8 cases (23%) and remyelination in 9 (26%). Morphometric analysis showed a predominant loss of myelinated fibers in 92% of the patients. Quantification of myelinated fiber loss in 11 patients revealed a remarkable decrease in large caliber fibers. Scarce mononuclear cells were observed in 17 cases. No virus-like elements were seen. The morphological features found in this study indicate that, regardless of the clinical presentation, peripheral nerve lesions of the epidemic neuropathy in Cuba correspond to an axonal neuropathy. These lesions are compatible with nutritional, toxic, or metabolic etiologies. An inflammatory etiology would be unusual with these lesions.

Seasonal and epididymal maturation of stallion spermatozoa

Epididymal sperm maturation in the stallion was analysed using eight epididymides and deferent ducts from healthy animals. Samples were obtained in June-July and October-November (resting and breeding periods, respectively). Epididymides were divided into head, body and tail. Sperm samples were submitted to a routine seminogram, chromatin decondensation test (Lung, 1972) and sperm velocity determination (Makler, 1980). Results demonstrate that stallion spermatozoa achieve maturation in the transition between the head and body of the epididymis as revealed by chromatin decondensation. Objective and subjective motility and sperm velocity acquire maximal values in the cauda epididymis where they are similar to the values seen in the vas deferens. No differences were found in the proximal and medial segments of the epididymis regarding these parameters when sexually active and resting animals were compared.