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Biomedical subjects

J Becker

Publications and source records attributed to J Becker.

At least 127 records · Page 7Linked to original sources
PubMed1994

The influence of the cause of death and age on human corneal metabolism.

PURPOSE: Little is known about the metabolic status of human corneas before transplantation. The authors attempted to determine the influence of both cause of death and age on the corneal metabolism. METHODS: Adenosine-triphosphate (ATP), adenosine-diphosphate (ADP), glucose, and lactate were measured in the stroma and endothelium of 30 human corneas. The corneas were divided into four groups according to cause of death and four groups according to age. Corneas from donors with diabetes were excluded. RESULTS: Corneas from patients who died suddenly--because of cardiac infarction, for example--have good metabolic status even 24 hours after death. In corneas of patients with cancer or sepsis, the metabolism has run down. In comparison, corneas from patients with cancer are in better metabolic condition than those from donors with sepsis because they have adapted to catabolism. Corneas donated from patients with renal insufficiency show results somewhere in between. Statistical evaluation revealed significant differences in ATP concentrations for corneas from donors who died suddenly and from patients with renal insufficiency compared to corneas from patients with sepsis. It could be shown that glucose concentrations as a resource for metabolism increase with age. The best ATP-ADP ratios were found in the group of 40- to 59-year-old donors. Nevertheless, differences between the age groups were not statistically significant. CONCLUSION: From our results it can be concluded that the cause of death and systemic metabolism have an influence on corneal metabolism. Results concerning donor age reflect the well-known fact that donor age has no influence on the quality of keratoplasty material.

Adenosine Diphosphate↗
PubMed1994

HIV-1 nucleic acids localize to the spermatogonia and their progeny. A study by polymerase chain reaction in situ hybridization.

The purpose of this study was to determine the histological distribution of in situ polymerase chain reaction (PCR)-amplified HIV-1 nucleic acids in the male genital tract to elucidate the mechanism of sexual transmission of AIDS. Viral DNA was detected in the testicular tissue of 11 of 12 men with HIV-1 infection using the PCR in situ hybridization technique. The amplified viral DNA localized to many spermatogonia, spermatocytes, and rare spermatids. Relatively few viral infected macrophages were noted, mostly in the prostate. The viral infection was activated given the presence of cDNA sequences consistent with genomic and multiple spliced transcripts as determined by reverse transcription in situ PCR. PCR-amplified viral nucleic acids were not detected in the epithelial of the prostate, epididymis, seminal vesicles, or penis in men with AIDS nor in any genital tract tissues from three boys who died of AIDS acquired in utero. The demonstration that HIV-1 selectively infects the spermatogonia and their progeny suggests that this may serve as a primary source of venereal spread of the virus. Concomitant destruction of these cells by HIV-1 may also explain the marked inhibition of spermatogenesis and severe atrophy that characterizes the testes in AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Immunological reactions against PMMA lens material?

We investigated the kind of reactions that occur after injection of a PMMA lens powder into the back skin of rabbit. The lens powder was suspended in NaCl and incomplete Freund's adjuvant to reinforce the immunological reaction. The ELISA test was carried out to detect antibodies against the lens material as a whole and against the UV absorber Tinuvin in particular. We also performed histological and immunohistochemical examinations of the back skin. We did not detect antibodies against either the lens material or against Tinuvin. Histological examination showed a foreign-body or delayed allergic reaction against the lens material. Lymphocytes surrounding the PMMA were found to be mainly of the T-type, which supports the results of the ELISA test.

Animals↗
PubMed1993

Genetic mediation of infanticide and parental behavior in male and female domestic and wild stock house mice.

Infanticide is a reproductive strategy found in many mammals, especially rodents. The proportion of male and female house mice (Mus domesticus) that are either infanticidal or noninfanticidal is strain specific and varies widely from stock to stock. Male house mice also show strain-specific variation in the behavioral mechanisms that inhibit infanticidal individuals from killing their own offspring. The adult offspring generated from reciprocally crossed CF-1 and Wild stock house mice were tested for their behavior toward newborn pups. In male CF-1 x Wild hybrids, the proportion of infanticidal and noninfanticidal males matched with their maternal phenotype, whereas female CF-1 x Wild hybrids exhibited a proportion of behaviors typical of the CF-1 phenotype, regardless of their mother's genotype. Our results suggest three conclusions: first, that infanticide is a highly labile and heritable behavior in both sexes; second, that there is a sex difference in the genetic substrate that regulates the inheritance of infanticidal behavior; and third, that selection pressures in male mice may operate independently on the mechanisms that promote spontaneous infanticidal behavior versus the mechanisms that inhibit infanticide.

Agonistic Behavior↗
PubMed1993

Distribution of immunocompetent cells in oral Kaposi's sarcoma (AIDS).

Fifteen biopsy specimens of oral AIDS-associated Kaposi's sarcoma (KS), 19 biopsy specimens of uninvolved oral mucosa of HIV-seropositive patients (HIV+) and 22 biopsy specimens of oral mucosa of HIV-seronegative persons (HIV-) were analysed for the distribution of CD4+ and CD8+ lymphocytes and HLA-DR+ cells. The results were statistically evaluated. According to their clinical appearance KS were classified as flat lesions (n = 10) or exophytic tumours (n = 5). KS lesions of both clinical groups as well as uninvolved mucosa of HIV+ patients revealed infiltration with CD4+ cells. In flat, patch-like KS there was a marked increase of CD8+ cells compared to HIV- mucosa, while their numbers decreased in later tumour stages. In both, flat and exophytic KS the number of HLA-DR+ cells was significantly higher than in uninvolved mucosa of HIV+ and HIV- persons. These findings may reflect the local influence of KS growth factors on the inflammatory reaction in the setting of systemic immunosuppression.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Outpatient management with oral corticosteroid therapy for obstructive conditions in chronic granulomatous disease.

We report the outpatient management of three patients with X-linked chronic granulomatous disease, two of whom had episodes of gastric outlet obstruction and another, urinary bladder obstruction. These obstructive conditions were successfully treated with 2-week courses of orally administered corticosteroids with or without the addition of orally administered clindamycin. There were no infectious or other adverse reactions.

Administration, Oral↗
PubMed1993

Semiotic aspects of cognitive development: illustrations from early mathematical cognition.

The premise of this article is that cognitive development involves both conceptual and semiotic achievements. From this perspective, the authors emphasize the distinctness of the semiotic issues and develop a differentiated appreciation of semiotic aspects of cognition, particularly in the field of elementary mathematical cognition. The authors provide semiotic analyses of the differences between counting, adding, and multiplying and of the conventional place-value sign system. The authors introduce the concept of the field of reference of a sign, the differentiation of the field into foreground and background, and the dynamics within the field of reference. Finally, the authors relate these ideas to the dynamics between two dimensions of semiotic relations: the sign-referent dimension and the sign-sign dimension.

Child↗
PubMed1993

[Tarsoconjunctival advancement--a surgical procedure in cicatricial entropion with marginal tarsus deformation].

BACKGROUND: After severe chemical and thermal burns, and in chronic inflammatory conditions of the conjunctiva frequently scarring of the tarsal plate with distortion of the eyelid margin and keratinization of the tarsal conjunctiva could be found. This condition is accompanied with chronic inflammation and malposition of the eyelids resulting in entropion and trichiasis. PATIENTS AND METHODS: A surgical procedure is introduced separating the scarred and shortened tarsal plate from the cutis-muscle sheet. After excision of tarsal scar tissue and of the marginal metaplastic tarsus a new eyelid margin is formed by tarso-conjunctival advancement, correcting trichiasis and cicatricial entropion. During the time from August 1984 to December 1991 this surgical procedure was conducted on 16 patients, correcting 18 upper and 4 lower eyelids. 11 patients suffered from severe chemical and thermal burns, 2 patients from Stevens-Johnson-syndrome, 2 patients from ocular pemphigoid and 1 patient from herpes zoster infection. RESULTS: All patients were examined at least once in the first 6 postoperative months, 11 patients are still under continuing outpatient review. The mean follow-up time is 27 months, the minimum follow-up period is 7 months. In 7 patients the surgical procedure prepared conditions for a successful keratoplasty and in 5 other cases the keratopathy healed. In 4 cases a recurrence of the entropion occurred (18% recurrence rate). CONCLUSIONS: The presented surgical procedure is a promising alternative to more complicated procedures for correcting cicatricial entropion with keratinization of the marginal tarsus.

Adult↗
PubMed1993

Recombinant human GM-CSF treatment of neutropenia in glycogen storage disease-1b.

PURPOSE: Recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) was administered to two patients with glycogen storage disease, type 1b (GSD-1b), with chronic neutropenia, neutrophil dysfunction, and recurrent infections in an effort to increase neutrophil counts and increase resistance to infections. PATIENTS AND METHODS: The patients' baseline absolute neutrophil counts (ANC) ranged from 56 to 480 cells/mm3 despite increased granulocyte precursors in the bone marrow. GM-CSF was given s.c. at starting doses of 500 micrograms/m2/day divided into two doses. RESULTS: After 48 h, ANC rose to 2,025 cells/mm3 and 3,132 cells/mm3, respectively. Absolute eosinophil counts also rose to 1,048 cells/mm3 (24%) and 4,820 cells/mm3 (33%) on days 10 and 9 in the two patients. Although an initial 10-day course of GM-CSF was tolerated in one patient without significant reactions, subsequent s.c. injections of GM-CSF were complicated by increasingly painful local reactions that necessitated discontinuation after 7 to 8 days. Intravenous infusion was associated with a febrile systemic reaction. Despite lack of improvement in neutrophil superoxide anion generation measured in one, both patients demonstrated unusually rapid healing of cutaneous infections on GM-CSF. CONCLUSION: Our experience suggests that GM-CSF may be useful for short-term treatment of serious infections in GSD-1b. However, alternate dosage schedules or different preparations of GM-CSF to diminish local reactions would be required for long-term maintenance therapy. Granulocyte colony stimulating factor (G-CSF) has also been shown to increase neutrophils in this disease and has not been associated with allergic reactions.

Adolescent↗
PubMed1993

Immunohistochemical distribution of collagens type I, III, IV and VI, of undulin and of tenascin in oral fibrous hyperplasia.

The distribution of collagens type I, IV and VI, of procollagen type III, of undulin and of tenascin was studied in 10 lesions which were clinically and histologically diagnosed as localized oral fibrous hyperplasias. The immunohistochemical distribution of these proteins was similar to that observed for normal oral mucosa. Undulin showed a pattern of parallel fibers throughout. Collagen type VI was pronounced in the subepithelial connective tissue, whereas the collagen fiber bundles were equally reactive for collagens type I and III. Tenascin was observed close to the subepithelial basement membrane and in proximity to collagen fiber bundles in the upper connective tissue. The present findings indicate that oral fibrous hyperplasias that are probably caused by inflammation or chronic irritation show the differentiated and ordered pattern of extracellular matrix proteins characteristic of normal oral mucosa.

Adult↗
PubMed1993

A rare case of bilateral congenital corneal malformations.

We report the case of a now 6-year-old girl who was born with different abnormalities in each eye. The right eye showed a total sclerocornea. At the age of 4 years we performed a perforating keratoplasty. On the left eye a large staphyloma developed. The staphyloma was excised and a cornea with a scleral rim was fixed in. This transplant became cloudy under a conjunctival flap and blepharoplasty. In addition to the clinical follow-up, histological and immun-histochemical examinations of the corneas were carried out.

Child↗
PubMed1993

Use of preprocedural tests by interventional radiologists.

A direct survey was taken of 1,238 members of the Society of Cardiovascular and Interventional Radiology (SCVIR) concerning the routine use of 14 tests (most frequently, prothrombin and partial thromboplastin times, complete blood cell counts, and blood urea nitrogen and serum creatinine levels) performed before 10 invasive percutaneous procedures (peripheral angiography, neuroangiography, transluminal angioplasty, thrombolysis, percutaneous needle biopsy, abscess drainage, percutaneous nephrostomy, biliary drainage, myelography, and venography). The survey was undertaken to determine the current practices and appropriateness of current routine use of preprocedural tests. The response rate was 34%, representing a cumulative annual volume of 322,208 cases. The practice of performing routine preprocedural tests is common among interventional radiologists. Data provided by this survey suggest that use of these tests is excessive. Adherence to suggested proposals derived from previously reported experience would result in an annual estimated savings of $20.0-$34.9 million (extrapolated for all procedures performed by SCVIR members in 1989).

Diagnostic Tests, Routine↗
PubMed1993

Effect of history of alcoholism or major depression on smoking cessation.

The authors examined the influence of a history of alcoholism or major depression on smoking cessation for 220 subjects. The success rate of recovering alcoholics was comparable to that of nonalcoholics, comorbidity of alcoholism and major depression exerted a detrimental effect, and smoking cessation did not precipitate an alcoholic relapse.

Adult↗
PubMed1993

Distribution of undulin, tenascin, and fibronectin in the human periodontal ligament and cementum: comparative immunoelectron microscopy with ultra-thin cryosections.

We studied the ultrastructural localization of three distantly related glycoproteins of the extracellular matrix, undulin, tenascin and fibronectin, in decalcified sections of human periodontal ligament (PL) and cementum. Undulin was associated with tightly packed major collagen fibrils and not with microfibrils, indicating that this protein may be involved in the supramolecular and functional organization of collagen fibrils into flexible bundles. Tenascin was found on globular masses between less densely packed collagen fibrils, thus displaying a pattern quite distinct from that of undulin. Fibronectin was noted in bulky material between the cross-striated fibrils, often surrounding individual fibrils like garlands, and in the microfibrillar meshwork extending from cross-striated fibrils. The three glycoproteins displayed a distinct and unique pattern of distribution in PL that can be correlated with their molecular structure and potential functions.

Adolescent↗
PubMed1993

Sex differences in EEG coherence in normal children.

The idea that sex differences in the execution of different mental tasks mean a different cerebral organization met contradictory results. Sex differences in brain electrical activity were reported by various authors. The EEG coherences show functional and anatomical interrelation, so they may reveal differences in brain organization. This paper tries to demonstrate how sex differences are manifested in EEG coherences, in 42 right-handed control children, 18 girls and 24 boys, aged 7.6 to 13.3. Since the effect of age is high on EEG measurements, regression against age was calculated and eliminated. The Z-transformed coherence values were compared by Student's t-test. The results obtained showed that girls had higher right intrahemispheric coherence values than boys in all bands. These sex differences were more numerous in the theta band. The interhemispheric differences were slight and girls had higher coherences in all bands except for the alpha band, where boys had higher interhemispheric coherence than girls. These results show slight but consistent differences in the functional organization of the right hemisphere by sex and reveal the necessity to elaborate separated EEG norms for boys and girls.

Adolescent↗
PubMed1993

Combined histochemical stains in the differential diagnosis of Cryptococcus neoformans.

Three combinations of histochemical stains were used to study 69 routinely processed tissues containing various "yeast-like" fungal organisms (Cryptococcus neoformans, Blastomyces dermatitidis, Coccidioides immitis, Histoplasma capsulatum, Paracoccidioides brasiliensis, and Candida albicans). Fontana-Masson stain combined either with mucicarmine or Alcian blue produced distinctive staining of C. neoformans (Fontana-Masson-positive wall and mucin-positive capsule) that was not identified in other fungi. The Alcian blue stain combined with periodic acid-Schiff reaction also was useful for fungal classification, because the Alcian blue component reacted with only C. neoformans (capsule) and B. dermatitidis (wall) and the periodic acid-Schiff reaction reacted with the cell wall and body of each fungus. We concluded that the combined histochemical stains used in conjunction with morphologic study of hematoxylin and eosin- and Gomori methenamine silver-stained sections are helpful in the differential diagnosis of yeast-like fungal organisms.

Alcian Blue↗