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Biomedical subjects

P Roche

Publications and source records attributed to P Roche.

At least 73 records · Page 4Linked to original sources
PubMed1993

Neuritis of the lateral femoral cutaneous nerve in leprosy.

Neuritis of the lateral femoral cutaneous nerve (meralgia paresthetica) is observed more frequently in leprosy than in nonleprosy patients, and its symptoms can easily be confused with those suggesting, e.g., ischialgia. The diagnosis can be confirmed by a diagnostic block with a local anesthetic solution. Analgesics, antiinflammatory drugs, bed rest and, in severe cases, therapeutic blocks were successfully applied in the treatment of the neuritis, and no surgical intervention was needed. Three leprosy patients with severe meralgia paresthetica are presented.

Adult↗
PubMed1993

Cytological needle aspiration of the nerve for the diagnosis of pure neural leprosy.

Pure neural (also called primary neuritic) leprosy manifests itself by involvement of only the nerve in the absence of skin lesions. Therefore, it sometimes can pose a diagnostic problem. Cytological needle aspiration of an affected nerve can be a valuable tool under such circumstances. The method as developed at Anandaban Leprosy Hospital, Nepal, is described and two cases are presented.

Adult↗
PubMed1993

Goodpasture's syndrome in aging. An experimental study on the rat. I.

The following hypothesis is proposed: Experimental lung disease in old rats is different from this disease in adult rats. In order to demonstrate this, we performed a morphometrical evaluation of the pulmonary state of two groups of rats at different ages and to which Goodpasture's syndrome had been induced. 115 Wistar rats were used. They were divided into four different groups as follows: 1) Healthy adult rats which had not been subjected to treatment; 2) diseased adult rats to which antipulmonary serum had been administered; 3) healthy old rats; and 4) diseased old rats. With the help of a computerized system, the length of the alveolar chord, the thickness of the alveolar wall and the surface of the bronchial-associated lymphoid tissue in each group was calculated. We also counted the number of alveolar macrophages (AM) with haemosiderin, the percentage of goblet bronchial cells and that of AM, lymphocytes and polymorphonuclear leukocytes of the broncho-alveolar lavage (BAL). The following results were obtained. When related to the diseased adult rats, the diseased old rats showed an increase in the alveolar chord and a decrease in the thickness of the alveolar wall, as well as in the number of AM with haemosiderin, goblet cells and BAL lymphocytes. These results support the proposed hypotheses, since the diseased adult animals showed signs of alveolar inflammation with interstitial edema, while in the diseased old animals these results are compatible with emphysema.

Aging↗
PubMed1993

Goodpasture's syndrome in aging. An experimental study on the rat. II.

The following hypothesis is suggested: if a lung disease is induced in an adult rat, then its lung, in the senile age, will be different from what is considered to be a normal senile lung. In order to demonstrate this, the pulmonary state of two groups of old rats, one of which had suffered from Goodpasture's syndrome in the adult age has been assessed morphometrically. Fifty-three Wistar rats were used. They were divided into two groups: 1) healthy old rats; and 2) diseased old rats. Antipulmonary serum was administered to the latter and they were sacrificed a year later. Making use of a computing system, we calculated the following data for each group: the alveolar chord length, the alveolar wall thickness and the surface of the bronchial-associated lymphoid tissue (BALT). The alveolar macrophages (AM) with haemosiderin which were found in the lung tissue were also counted and the percentage of goblet bronchial cells and that of bronchoalveolar lavage (BAL) cells was also assessed. From the results, the following points should be emphasized: in diseased old rats, an increase in the alveolar chord, a decrease in lymphocytes with an increase in the AM of the BAL, and a decrease in goblet cells and AM with haemosiderin occur, all of which are significant when these rats are compared to healthy old rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1993

[Cervical cystic lymphangioma in adults].

Cystic hygromas, infrequent in children, are even rarer in adults where they once were generally an unexpected operative findings. Now, with the progress in modern medical imaging the diagnosis can be suggested before operation. Analysis of the embryogenesis helps to explain the different anatomical and clinical forms and the relations of the cystic hygroma with neighboring tissues, particularly of renous origin, grases of cystic hygroma of the neck in adults are reported and discussed with 26 other well documented cases from the literature. The diagnosis can be confirmed only after operation and histological examination. Surgical removal is technically less difficulté in adults than in children and recurrences are rare.

Adolescent↗
PubMed1992

Limiting dilution analysis in leprosy.

Peripheral blood mononuclear cells (PBM) obtained from leprosy patients and healthy controls were cultured with Mycobacterium leprae and the control antigens, BCG and SKSD. Parallel cultures were supplemented with additional interleukin-2 (IL-2). On the basis of the level of response to M. leprae, leprosy patients could be divided into low, intermediate and high responders. The addition of IL-2 resulted in enhanced proliferation to antigen only by cells from intermediate responders. This effect was neither antigen specific nor was it confined to cells from leprosy patients. When limiting dilution analyses were performed on cells from 26 patients across the leprosy spectrum, no M. leprae-reactive lymphocytes were detected in cells from subjects with lepromatous disease. The precursor frequency for cultures containing M. leprae plus IL-2 was no greater than that of cultures containing IL-2 alone, thereby excluding the possibility of clonal anergy reversible with IL-2. This was observed in both untreated patients and those on long-term treatment, which made sequestration of antigen-reactive cells within leprosy lesions an unlikely explanation. On the other hand, M. leprae-reactive lymphocytes were detected in patients with tuberculoid and borderline tuberculoid disease and in two subjects with borderline lepromatous leprosy in type I reversal reaction. IL-2 reactive cells were detected in all patients regardless of clinical classification. Three 'suppressor' curves were obtained but were not confined to cells from lepromatous patients. Taken together, these findings suggest that the non-responsiveness to M. leprae characteristic of the great majority of multibacillary patients is due to an absence of antigen-sensitive T cells.

Antigens, Bacterial↗
PubMed1992

Expression of the alpha 6 beta 4 integrin in lesional skin differentiates bullous pemphigoid (BP) from epidermolysis bullosa acquisita (EBA).

The integrin alpha 6 beta 4 complex is a protein of the membrane of basal keratinocytes, localized at the surface of cells in contact with the basement membrane zone in normal skin. The expression of alpha 6 beta 4 was investigated in several autoimmune blistering skin diseases including bullous pemphigoid (BP), epidermolysis bullosa acquisita (EBA), bullous systemic lupus erythematosus (BSLE), and pemphigus vulgaris (PV) by an indirect immunofluorescence technique. In lesional bullous skin of BP, alpha 6 beta 4 expression was either absent, or in some cases represented an unusual irregular patchy staining. In contrast, in lesional bullous skin from EBA, BSLE, and PV, alpha 6 beta 4 expression was comparable to that observed in normal skin, i.e., a linear staining of the BMZ. Thus, analysis of the alpha 6 beta 4 integrin reactivity on lesional skin, in conjunction with the typical localization of collagen IV, allows a rapid and accurate distinction between BP and EBA.

Diagnosis, Differential↗
PubMed1992

Serological diagnosis of bullous pemphigoid (BP): comparison of the sensitivity of indirect immunofluorescence on salt-split skin to immunoblotting.

Specialized immunological assays are required for the accurate diagnosis of bullous dermatoses such as bullous pemphigoid (BP), epidermolysis bullosa acquisita and bullous lupus erythematosus. The aim of this study was to analyse and compare the sensitivity of indirect immunofluorescence (IF) on salt-split skin and immunoblotting for the detection of circulating autoantibodies in BP. Of the BP patients selected for the study, 74/79 (94%) had circulating autoantibodies detected by at least one of the two methods. Both methods had comparable sensitivity and detected BP-specific autoantibodies in 82-85% of the patients. Because 20% of the patients were found to be positive by only one of the methods, both methods should be used in the diagnosis of BP. Indirect IF on salt-split skin is easier to perform and is preferable in routine analysis, but Western blotting may be used as a complementary assay with sera showing no reactivity on salt-split skin.

Autoantibodies↗
PubMed1991

Molecular basis of symbiotic host specificity in Rhizobium meliloti: nodH and nodPQ genes encode the sulfation of lipo-oligosaccharide signals.

The symbiosis between Rhizobium and legumes is highly specific. For example, R. meliloti elicits the formation of root nodules on alfalfa and not on vetch. We recently reported that R. meliloti nodulation (nod) genes determine the production of acylated and sulfated glucosamine oligosaccharide signals. We now show that the biochemical function of the major host-range genes, nodH and nodPQ, is to specify the 6-O-sulfation of the reducing terminal glucosamine. Purified Nod factors (sulfated or not) from nodH+ or nodH- strains exhibited the same plant specificity in a variety of bioassays (root hair deformations, nodulation, changes in root morphology) as the bacterial cells from which they were purified. These results provide strong evidence that the molecular mechanism by which the nodH and nodPQ genes mediate host specificity is by determining the sulfation of the extracellular Nod signals.

Amino Acid Sequence↗
PubMed1991

Structural determination of bacterial nodulation factors involved in the Rhizobium meliloti-alfalfa symbiosis.

Extracellular signals produced by Rhizobium meliloti are able to induce root hair deformations and nodule organogenesis on alfalfa. The production of these signals is controlled by bacterial nod genes. To enable their isolation in significant amounts, an overproducting strain was constructed. These Nod factors were first extracted by butanol from the culture medium and further purified by reverse-phase high performance liquid chromatography, ion-exchange, and Sephadex LH-20 chromatographies. The structure of the major signal, called NodRm-1, was determined by mass spectrometry, nuclear magnetic resonance, 35S labeling, chemical analysis, and enzymatic degradation, and was shown to be a sulfated and acylated tetramer of glucosamine namely, beta-D-GlcpN(2,9-hexadecadie-noyl) - (1----4) - beta - D - Glc p Nac - (1----4) - beta - D - Glc p NAc - (1----4) - D - GlcpNAc-6-SO3H. Another Nod factor (called Ac-NodRm-1) was co-purified and identified as NodRm-1 acetylated on the C-6 of the nonreducing end sugar. NodRm-1 elicits root hair deformation specifically on alfalfa at a concentration less than 10(-10) M but has no effect on vetch (a heterologous host plant).

Acetylation↗
PubMed1990

Symbiotic host-specificity of Rhizobium meliloti is determined by a sulphated and acylated glucosamine oligosaccharide signal.

Rhizobia are symbiotic bacteria that elicit the formation on leguminous plants of specialized organs, root nodules, in which they fix nitrogen. In various Rhizobium species, such as R. leguminosarum and R. meliloti, common and host-specific nodulation (nod) genes have been identified which determine infection and nodulation of specific hosts. Common nodABC genes as well as host-specific nodH and nodQ genes were shown recently, using bioassays, to be involved in the production of extracellular Nod signals. Using R. meliloti strains overproducing symbiotic Nod factors, we have purified the major alfalfa-specific signal, NodRm-1, by gel permeation, ion exchange and C18 reverse-phase high performance liquid chromatography. From mass spectrometry, nuclear magnetic resonance, (35)S-labelling and chemical modification studies, NodRm-1 was shown to be a sulphated beta-1,4-tetrasaccharide of D-glucosamine (Mr 1,102) in which three amino groups were acetylated and one was acylated with a C16 bis-unsaturated fatty acid. This purified Nod signal specifically elicited root hair deformation on the homologous host when added in nanomolar concentration.

Acylation↗
PubMed1988

Filaggrin expression in normal and pathological skin. A marker of keratinocyte differentiation.

Filaggrin is a basic, histidine-rich protein synthesized by cells of keratinizing epithelia, that subserves major physiological functions in maturating epidermis. Its precursor, profilaggrin, constitutes a major component of kertohyalin granules. In this work the expression of profilaggrin/filaggrin was studied in 140 specimens of normal human adult and fetal skin, cultured epithelia before and after allo- and xeno-grafting, and several cases of keratinization disorders and tumours. An avidin-biotin-alkaline phosphatase technique was applied on deparaffinized tissue sections, by using a specific monoclonal antibody (AKH1) to profilaggrin/filaggrin. The results show that the expression of profilaggrin/filaggrin is variously altered in keratinization disorders, whereas in epithelial proliferations it seems to decrease with an increasing degree of dedifferentiation of the tumour. Therefore the expression of these antigens can be considered to be a sensitive marker of maturation of normal epidermis and provides a new tool for the study of differentiation of the surface epithelium in skin diseases.

Fetus↗
PubMed1988

Epithelial differentiation of human skin equivalents after grafting onto nude mice.

Human skin equivalents were developed in vitro with a unidimensionally retracted dermal equivalent made of human type I + III collagen and human MRC5 fibroblasts, and a multilayered epithelium grown in liquid medium from normal human keratinocytes in suspension. We investigated the degree of epidermal differentiation that could be achieved after in vivo grafting onto nude mice by means of light and electronmicroscopy as well as by immunohistochemistry. All transplanted grafts showed a primary take. The grafts formed an epidermis with a stratum corneum and from day 7 to 14 after transplantation a distribution of a 56.5 Kd keratin protein, involucrin, profilaggrin/filaggrin, and MHC-I antigens that was similar to what is noted in normal human epidermis. These data indicate that a full terminal differentiation was only achieved after in vivo transplantation of the cultured epithelium. Pigmentation was present, but no marker of Langerhans cells was seen at 4 weeks. Although there was no evidence of the dermal equivalent after 2 weeks, we noted a strong adherence of the graft to the wound bed, with the presence of type-IV collagen, laminin, and bullous pemphigoid antigen at the dermo-epidermal junction (day 7) and hemidesmosomes, a lamina lucida and a lamina densa (day 30). No epithelial damage was noted in spite of an inflammatory infiltrate in the underlying tissue. This represents a preliminary step in the use of such a skin-equivalent in the treatment of human patients with wounds.

Animals↗
PubMed1988

The expression of PNA-lectin binding sites and S-100 protein in histiocytic lesions of the skin. A comparative immunohistochemical study.

In this work the potential usefulness of antibodies to S-100 protein and the lectin Peanut Agglutinin (PNA) in the differential diagnosis of histiocytic lesions of the skin was assessed. Out of 54 deparaffinized specimens studied through an avidin-biotin-alkaline phosphatase technique, 35 proved to comprise S-100 (+) and 12 PNA (+) cells. The results show that antibodies to S-100 protein are useful in distinguishing the "X" (Langerhans' cell) from the "non-X"types of histiocytosis, and cast some shadow on the usefulness of the lectin PNA as a histiocytic marker. (Received May 5, 1987.)

Arachis↗
PubMed1987

Sex, handedness and weight discrimination.

Manual asymmetries in weight discrimination were investigated by testing 50 subjects with their left hand and 52 with their right hand, the groups being approximately balanced for sex and hand preference. Performance was better for the left-tested group, and for strongly handed males tested with the dominant hand. Female performance was unrelated to handedness. There was no overall superiority due to sex, males being superior with the dominant hand and females with the nondominant hand. The results are interpreted in terms of spatial hemisphere involvement, hand dominance, and the greater hemispheric specialization of males.

Adult↗