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L M Bechelli

Publications and source records attributed to L M Bechelli.

At least 37 records · Page 2Linked to original sources

[Ultrastructural aspects of the epidermis from a sun exposed and from a covered area in two cases of xeroderma pigmentosum (x. p.) and in two controls (author's transl)].

Xeroderma pigmentosum is rare among Caucasoids and seems to be rarer among Negroes. Advantage was taken of the observation of two cases in the latters to study the ultrastructure of the epidermis and to verify whether the findings were similar to those observed in the formers. The skin exposed to sunlight (forearm) and that from an covered area (buttock) were studied in the two cases and also in two controls, obviously from the same race. The tissue material was coded after each biopsy and identified only when the ultrastructural study was completed. The authors have noted vacuolization and rarely necrosis of melanocytes, great increase and polymorphism of melanosomes, abnormal melanization sometimes large masses of melanosomes and pre-melanosomes, some other aspects already described in x.p. They have also observed melanosomes disposed as cluster or grapes, and large and strange shaped keratohyaline granules in the squamous cell layer. Even in the unexposed skin there were polymorphism and increased amount of melanosomes. The macroscopic and ultrastructural changes of x. p. in the two Negroes were apparently similar to those observed in Caucasoids.

Adolescent

[Cutaneous dyschromia in three cases of phenylketonuria. Quantitative ultrastructural study of the basal layer of the epidermis (author's transl)].

The authors have studied skin color modifications in 3 cases of phenylketonuria and have observed the characteristic changes; fair skin and fair hair. In addition they noted hundred of pigmented pin point or slightly larger patches in the two more affected patients, in the areas exposed to sunshine. With regard to the ultrastructural study of the epidermis basal layer, the proportion of melanocytes in the two most severe cases was slightly higher than in the normal skin of 6 control subjects. Langerhans cells could not be acertained. The more severe was the disease the greater was the tendency for a lower proportion of keratinocytes containing melanin. There is a certain parallelism between the skin color modifications the biochemical examinations (blood level of phenylalanin and tyrosine) and the ultrastructural changes. The higher the blood level of phenlalanine and/or the more pronounced the disorders of skin color, the more evident would be the ultrastructural changes: higher proportion of melanocytes that usually do not produce the melanosomes, and lower percentage of keratinocytes with melanin. On the other hand, the ultrastructure of the basal layer would suggest the seriousness of clinical manifestations and/or the intesity of the metabolic error.

Child

[Quantitative ultrastructural study of the epidermis basal layer in the vitiligo patches and in the marginal hyperchromic and normal skin (author's transl)].

To avoid any bias, the ultramicroscopic examination was performed by the morphologist without knowing whether the material examined was from the vitiligo patch or from the marginal hyperpigmented and normal skin. Only at the end of the investigation, he was informed about the code of the material. He had also been informed about the possibility of receiving skin biopsies from a patient without vitiligo, what in fact was done with the inclusion of one case of albinism. Six cases of vitiligo have been studied. The melanocytes usually have not been observed in the vitiligo patches, where a variable number of Langerhans cells were seen. In the melanocytes reached about 17 p. 100 of the cellular population; Langerhans cells were absents. In the marginal normal skin the average proportion of melanocytes was near 10 p. 100 of the cellular population and the Langerhans have been observed only in one case (1.8 p. 100 of the population). Regarding the keratinocytes of the marginal hyperpigmented and normal skin, respectively 75 p. 100 and 59 p. 100 contained melanin; in the vitiligo patches only in one case keratinocytes contained melanin (2.8 p. 100 of the keratinocytes population as an average).

Adult

Impairment of reactivity to lepromin by mycobacterial antigens related to, or identical with, Mycobacterium leprae.

Three hundred and twenty young children were injected with Bacillus Calmette-Guerin (BCG) saline, or with one of the mycobacterial cytoplasmic antigens related with Mycobacterium leprae. At an appropriate time thereafter they were tested for dermal hypersensitivity to the antigens and for reactions to lepromin. Whereas all the antigens induced cell-mediated immunity, the incidence and intensity of late response to lepromin were significantly reduced in children preinjected with the cytoplasmic mycobacterial antigens, as contrasted with increased lepromin reactivity in the BCG group and with the findings in saline-injected children.

Antigens, Bacterial

Bacteriological status (point prevalence) of lepromatous outpatients under sulfone treatment.

The study concerns 337 outpatients with lepromatous leprosy who had been receiving dapsone treatment for 1-26 years-69% of them regularly and 31% irregularly. Routine bacterial examination (10 min per slide) by a paramedical technician showed only 50% of these patients to be bacteriologically positive. This rate attained 99% when each slide was examined for 30-60 min by a qualified bacteriologist. Other factors-apart from the limited action of sulfones-might account for these unexpected results: the material was collected by an experienced leprologist; the disease was still clinically active in 75% of the patients; about 25% of them had been treated for only 1-4 years; and the intake of dapsone in long-term treatment gradually decreases.

Humans

BCG vaccination of children against leprosy: nine-year findings of the controlled WHO trial in Burma.

The leprosy incidence rates so far in the vaccinated and unvaccinated children aged 5-9 and 10-14 years are similar. The BCG-vaccinated children aged 0-4 years at intake had an incidence rate lower than that of children in the control group. BCG vaccination did not protect household contacts or children aged 5-14 years not exposed in the household, and did not influence the distribution of the forms of leprosy in the cases detected. The lepromin reaction in relation to the age at intake was consistently stronger in the vaccinated children than in those of the control group; the younger the age group the more pronounced was the difference, which was only slight in the age group 10-14 years at intake. If the results of the late lepromin reaction are related to the age at onset (when the children are older than at intake), the differences between the BCG and the control groups tend to decrease. It does not seem that the BCG-vaccinated children suffer from a less serious form of leprosy than the nonvaccinated children (most of them nonreactors to tuberculin).

Adolescent

Site of early skin lesions in children with leprosy.

Most of the data on the site of early skin lesions in leprosy were obtained from the case histories of registered patients, mainly those in leprosy institutions and who had had the disease for one or more years. Such information should be treated with reservation. The purpose of this study was to determine, in a highly endemic area, the site of early skin lesions in 28 220 children who, after screening, were kept under close surveillance and re-examined yearly. In 469 patients with a single lesion, this was most often located on the thighs or buttocks, followed by the arms, forearms, legs, and lumbar region. This finding is of interest mainly for diagnostic purposes. The predilection of single early lesions for certain regions of the body does not appear to depend on whether these parts are exposed or not.

Child

Late lepromin reaction in untreated patients with indeterminate leprosy under 21 years old in Burma.

Studies on lepromin reactivity in indeterminate (I) leprosy have usually been carried out among patients in whom the disease appeared 1 or more years before testing. This may result in misleading findings because a high proportion of patients, probably those showing moderate or strong lepromin reactions, seem to progress to the tuberculoid pole of leprosy in a relatively short time (<1 year), and in many the lesions heal spontaneously. The object of the present study was to determine the frequency and intensity of late lepromin reactions (macroscopic readings) in untreated I patients aged under 21 years who had had the disease for less than 1 year. Of 209 patients tested with lepromin containing 160 x 10(6) bacilli/ml only a small proportion ( not equal 7%) showed a negative or doubtful lepromin reaction, while 61.5% were 2+ and 3+ reactors. These findings indicate that a favourable outcome may be expected in most I cases in the trial area.

Adult

Correlation between leprosy rates in villages different distances apart.

In order to study the role of genetic factors in susceptibility to leprosy infection, the prevalence of leprosy in 118 pairs of Burmese villages different distances apart was investigated. The distribution pattern of the correlation coefficients for leprosy rates was compared with that known to occur for genetic markers under similar conditions. The correlation coefficients decreased rapidly as the distance between the pairs of villages increased and then showed periodicity with distance, becoming negative at almost regular intervals of 4 km: negative values were preponderant for villages more than 25 km apart. Thus with this set of correlations it was not possible to fit a monotonically decreasing function of the type that would fit similar data for a genetic marker

Genetics, Population

BCG vaccination of children against leprosy: seven-year findings of the controlled WHO trial in Burma.

A controlled study of the efficacy of BCG vaccination for the prevention of leprosy began in Burma at the end of August 1964. This paper presents the findings after 7 years-i.e., the results of 6 annual follow-up examinations up to the end of June 1971. The incidence rate in BCG-vaccinated children 0-4 years of age at intake was lower than that in children in the control group. The protection conferred by BCG was relatively low (44%) and applied only to early cases of leprosy, the great majority tuberculoid cases. BCG vaccination did not protect household contacts or children 5-14 years of age who were not exposed in the household. This reduction must be interpreted in the light of several factors: form of leprosy, bacterial status, lepromin reactivity, evolution of cases, and level of endemicity. Consequently it does not seem probable that the reduction in incidence would substantially affect the pattern or trend of the disease in an area similar to that where the study is being carried out; the probability would be much lower if not nil in regions of relatively low endemicity (1-2 per 1 000 or less).

Adolescent

Some epidemiological data on leprosy collected in a mass survey in Burma.

In the WHO Leprosy BCG Trial in Burma a mass survey was undertaken to determine whether children had been exposed to patients with leprosy and, if so, the form of the index case. This paper presents the most important epidemiological data collected in this survey. The prevalence rate was 31.6 per 1 000. It seems that even if the prevalence rate is very high the L rate does not increase accordingly. The high T rates in areas of high endemicity seem to be related mainly to the degree of spreading of leprosy, even to persons who react to lepromin. Comparison of the results with data available for the area before the survey was made shows that 87% of the L cases had already been detected and that 54% of the T cases had not. There was a tendency for high L rates to be associated with high prevalence rates. The results do not suggest that any particular age group has greater susceptibility or resistance; the prevalence rates seemed to be related mainly to the age when exposure occurred. A higher prevalence of leprosy in males started to appear in the 10-14-year age group, and after the age of 15 the difference became impressive. Biological, socio-economic, and environmental factors seem to be responsible for the level of endemicity, which does not seem to be essentially or primarily related to ethnic origin.

Adolescent

Further information on the leprosy pproblem in the world.

Information was obtained for the period 1966-70 concerning the number of registered cases, the number of cases that were inactive and released from control, the number of inpatients and of institutions for inpatient care, the proportion of lepromatous, tuberculoid, and indeterminate patients, and the frequency of disabilities.Comparison of the data from different countries was made difficult by non-uniform use of epidemiological terminology. In the circumstances, it would be hazardous to make an appraisal of the leprosy programmes in many of the countries, and it is difficult to determine correctly the trend of the endemics in these countries. The data collected suggest that the total number of estimated cases has not changed substantially in the last 5 years.

Africa

WHO co-ordinated short-term double-blind trial with thalidomide in the treatment of acute lepra reactions in male lepromatous patients.

The treatment of lepra reactions constitutes one of the most serious problems in leprosy. For this reason, the first reports in 1965 of the favourable results obtained with thalidomide aroused considerable interest and led WHO, in 1967, to carry out a trial with the co-operation of four centres. A short-term double-blind trial was designed to study the effect of thalidomide, in comparison with acetylsalicylic acid, in the treatment of acute lepra reactions in male lepromatous patients. Acetylsalicylic acid was used instead of a placebo because of its antipyretic and analgesic activity. Because of the severe adverse reactions that may be caused by thalidomide, mainly the teratogenic effects, only males were included in the trial.The results of this short-term study seem to confirm previous reports of the efficacy of thalidomide and indicate that acetylsalicylic acid also seems to be helpful in the management of certain symptoms of lepra reactions.

Acute Disease