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Biomedical subjects

J Becker

Publications and source records attributed to J Becker.

At least 109 records · Page 6Linked to original sources

Psychiatric disorders in spouse caregivers of care recipients with Alzheimer's disease and matched controls: a diathesis-stress model of psychopathology.

To test a diathesis-stress model of psychopathology, the authors examined the rates of current and lifetime psychiatric disorders in 82 spouse caregivers of Alzheimer's disease (AD) patients and 86 demographically matched controls. Caregivers and controls did not differ in the prevalence of disorders before the onset of care recipients' AD (or during a similar time period for the controls); caregivers experienced more depressive-anxiety disorders after the onset of patient's AD than controls. This study strongly supported the 3 key components of a diathesis-stress interaction. First, caregivers with a psychiatric history prior to the onset of patient's AD were more likely than caregivers with no history to receive a diagnosis after the onset of AD. Second, a similar relationship existed for controls. Finally, caregivers with a psychiatric history were more likely to experience a recurrence after the onset of AD than controls with a psychiatric history. These findings indicate that the diathesis of psychiatric history and the stress of caregiving interact, resulting in the observed group differences in the prevalence of psychiatric disorders.

Aged↗

Altered expression of extracellular matrix proteins and integrins in oral lichen planus (OLP).

The immunohistochemical distribution of collagens type I, III, IV, V, VI, of undulin and tenascin, and of integrins alpha 2, alpha 3, alpha 4, alpha 5, alpha 6 and beta 4, was studied in 14 biopsies of oral lichen planus (OLP), 5 biopsies of orthokeratinized gingiva and 4 biopsies of oral fibrous hyperplasia. The localization of extracellular matrix proteins showed altered expression in OLP when compared to normal oral mucosa, with two principal patterns corresponding to the reticular or atrophic type. Whereas in the reticular type a focal loss of immunoreactivity for collagen types I, III, V, VI and undulin was noted in areas with a cellular infiltrate, in the atrophic variant almost complete loss of immunoreactivity of the subepithelial extracellular matrix was found. There was no clear correlation between the distribution of extracellular matrix proteins and their integrin receptors. The present findings suggest that the autoimmune reaction in OLP might not be primarily targeted to oral keratinocytes but to an unknown antigen in the connective tissue stroma. The changes in the subepithelial extracellular matrix associated with the inflammatory reaction might, especially in the atrophic variant, impair the cross-talk between epithelium and mesenchyme and favour both the loss of barrier function and the development of erosions in the clinical course of the disease.

Adult↗

Mapping of digested and undigested random amplified microsatellite polymorphisms in barley.

The broad use of microsatellites as a tool for constructing linkage maps in plants has been limited by the need for sequence data to detect the underlying simple sequence repeats. Therefore, random amplified microsatellite polymorphisms (RAMPs) were studied as an alternative approach for barely mapping. Labelled (GA)n simple sequence repeat primers were combined with RAPD primers of different length and sequence to generate RAMPs. To get additional polymorphisms (called dRAMPs), the obtained products were also analysed after digestion with MseI. There were 0-11 polymorphisms found per primer combination. Sixty RAMPs/dRAMPs identifying 40 new loci were mapped onto a barley RFLP map. The new DNA markers are found on all chromosomes and they increased the length of the barely map by 174 cM to a total of 1270 cM. Interestingly, the RAMPs/dRAMPs caused stretching effects in genome areas where stretching was also observed for AFLPs.

Base Sequence↗

[Ethanol ingestion following Antabus overdose: acetaldehyde-induced cardiological emergency].

The differential diagnosis of chest pain is challenging, when the clinical presentation appears pathognomonic, yet conventional diagnostic tests fail to reveal the suspected cause. We report the case of a 38-year-old patient who had an acetaldehyde intoxication (antabuse syndrome) in the setting of disulfiram overdose and ethanol ingestion. The patient presented with severe angina pectoris. Coronary artery disease was suspected, because the patient had risk factors and electrocardiographic repolarization changes were present. During the further investigation it became evident that symptoms were solely caused by acetaldehyde intoxication following disulfiram and alcohol ingestion. Toxic levels of acetaldehyde were found in the patient's serum. Coronary artery disease was ruled out by cardiac catheterization.

Acetaldehyde↗

[Hepatitis C virus: results of detection in several high risk groups in the X region of Chile].

The aim of this study was to determine the prevalence of hepatitis C virus antibodies in high risk patients coming from Valdivia, Osorno and Puerto Montt. Fifty-six patients in hemodialysis, 51 renal graft recipients, 42 cirrhotics and 14 patients with acute non A non B hepatitis were studied. Antibodies were detected with a second generation ELISA technique and positive cases were confirmed with RIBA. All hemodialysis patients and renal graft recipients were negative for hepatitis C virus antibodies. In one non alcoholic patient with cirrhosis, a positive ELISA was confirmed with RIBA. Six patients with acute hepatitis had positive ELISA tests but none was confirmed with RIBA. It is concluded that the prevalence of hepatitis C virus antibodies in this region of Chile is very low.

Acute Disease↗

Remarks on the vitality of the human cornea after organ culture.

The purpose of this study was to obtain further information on the viability of organ-cultured human cornea. We thus used a specific staining method for succinate dehydrogenase (SDH), which is located in the membrane system of vital mitochondria. We examined fresh and long-term-cultured human corneas. After an initial incubation period in dextran-free culture medium, corneas were stored in a medium containing dextran. With respect to different appearances of the SDH staining, minimal essential medium without dextran seems to have a positive effect on the condition of epithelial cells. After renewal of the medium, keratocytes showed a brief improvement followed by a delayed deterioration, while the endothelial cells were severely damaged. However, best results for all three cell types were observed on the fourth day in a medium containing dextran. We therefore conclude that these corneas were best suited for transplantation.

Adolescent↗

High dose methotrexate infusion with leucovorin rescue for treatment of ectopic pregnancy.

The purpose of this article is to evaluate the effectiveness, side effects, and complications of high dose methotrexate infusion with leucovorin rescue in select patients with ectopic pregnancy. Between January 1991 and November 1994, 28 patients with ectopic pregnancies were prospectively treated with methotrexate (100 mg/m2 intravenous bolus followed by a 200 mg/m2 infusion over six hours) with leucovorin rescue. Twenty-seven of 28 patients (96%) were successfully treated. Only one patient (4%) required a second course of methotrexate to reach a normal hCG titer. One patient failed methotrexate infusion 45 days after treatment at a hCG titer of 12 mIU/mL. No Gynecologic Oncology Group grade 3 or 4 clinical, biochemical or hematologic toxicities occurred. Uterine bleeding and abdominal pain, not requiring transfusion or hospitalization, occurred in 71% and 56% of patients. The authors conclude that high dose methotrexate infusion with leucovorin rescue is a highly effective, well tolerated, nonsurgical treatment for select patients with ectopic pregnancy.

Abdominal Pain↗

Heat-shock proteins as molecular chaperones.

Functional proteins within cells are normally present in their native, completely folded form. However, vital processes of protein biogenesis such as protein synthesis and translocation of proteins into intracellular compartments require the protein to exist temporarily in an unfolded or partially folded conformation. As a consequence, regions buried when a polypeptide is in its native conformation become exposed and interact with other proteins causing protein aggregation which is deleterious to the cell. To prevent aggregation as proteins become unfolded, heat-shock proteins protect these interactive surfaces by binding to them and facilitating the folding of unfolded or nascent polypeptides. In other instances the binding of heat-shock proteins to interactive surfaces of completely folded proteins is a crucial part of their regulation. As heat shock and other stress conditions cause cellular proteins to become partially unfolded, the ability of heat-shock proteins to protect cells against the adverse effects of stress becomes a logical extension of their normal function as molecular chaperones.

Animals↗

Sonographic diagnosis of acute appendicitis in children.

The authors performed graded compression abdominal ultrasound (US) examinations in children with suspected acute appendicitis, whose clinical presentation was atypical. Abdominal US examination results were 95% accurate, far exceeding that reported for other imaging modalities. The sensitivity was 86%, the specificity was 98%, and the positive and negative predictive values were 96% and 94%, respectively. A positive sonogram made the likelihood of acute appendicitis 50 times greater compared with the pretest clinical impression. In addition, the use of US permitted identification of other pathological conditions that manifest similar symptoms and signs. The authors conclude that, with proper experience, US can be extremely useful in assisting the surgeon to markedly decrease the number of unnecessary appendectomy procedures, without increasing the risk of perforation.

Abdomen↗

Enhancement of bone ingrowth into a porous hydroxylapatite-matrix using a resorbable polylactic membrane: an experimental pilot study.

The objective of this pilot study was to study bone ingrowth into porous hydroxylapatite (HA) blocks using a polylactic membrane for guided tissue regeneration. Porous HA blocks were placed on both sides of the mandible and of the ilium in five Göttingen minipigs. On one side a polylactic membrane was used to cover the blocks. After 5 months, the blocks with the membrane covering showed complete bony penetration of the HA matrix both in the mandible and the ilium. The blocks without the membrane covering showed substantially less and irregular bone ingrowth after placement on the mandible and poor ingrowth after placement on the ilium. The newly formed bone in the blocks from the ilium showed a cancellous structure while bone tissue inside the blocks from the mandible exhibited a dense cortical appearance. The polylactic membrane was nearly completely degraded at the time of investigation.

Animals↗

Odontogenic myxoma--characterisation of the extracellular matrix (ECM) of the tumour stroma.

In order to elucidate the origin of the odontogenic myxoma, the composition and the structural organisation of the extracellular matrix (ECM) of this tumour were characterised. Collagen type I, VI, procollagen type III, undulin, tenascin and fibronectin were demonstrated in biopsy material of 4 cases by polyclonal antibodies. The tumour stroma showed a pronounced reaction for collagen type I. Fibroblasts displayed an intense intracytoplasmatic reaction for procollagen type III, and collagen type I was not found in the fibroblasts of the adjacent normal oral mucosa. In contrast to the surrounding connective tissue, label for collagen type VI was weak, as was the reaction for fibronectin and tenascin. Undulin was almost undetectable. The immunohistochemical results suggest that the odontogenic myxoma is characterised by an as yet unobserved structural organisation of ECM proteins, a secretion defect of fibrillar collagens type I and III with no resemblance to physiological tooth development.

Adult↗

Perceptions of parental and peer attachments by women with mood disorders.

The relationship between perceptions of parental and peer attachments at various ages and adult mood disorders was examined in 156 women classified as having bipolar disorder or unipolar depression or as nonpsychiatric controls. Nonpsychiatric controls reported a decreased attachment to their parents over time, but they also reported an increased closeness to their mothers in adulthood following a distant adolescence. Never hospitalized, moderately depressed subjects showed a similar trend toward decreased relatedness, but moderately depressed subjects did not report reestablishment of a close relationship with their mothers after adolescence. Severely depressed and bipolar subjects reported little attachment to their mother at all ages. Bipolar subjects also reported little connectedness to their fathers throughout their lifespan and severely depressed women felt less attached than nonpsychiatric controls to peers during development. None of the psychiatric groups reported difficulties with parental overcontrol.

Adult↗

Dependency, self-criticism, and perceptions of socialization experiences.

This study explored the relationship of dependency and self-criticism to perceptions of socialization experiences using 132 bipolar, nonbipolar depressed, and nonpsychiatric control female subjects. After controlling for level of depression and diagnosis, dependency was related to a distant relationship with fathers during development and was marginally related to perceptions of increased parental attention and overindulgence. Self-criticism was related to perceptions of difficulties in the quality of affective bonds with fathers and peers during childhood and was related marginally to perceptions of increased paternal power and control during development. No unique socialization experiences were associated with high dependency and self-criticism jointly, but women with both dispositional tendencies were likely to be severely depressed.

Adult↗

Distribution of procollagen type III, collagen type VI and tenascin in oral submucous fibrosis (OSF).

The distribution of procollagen type III, collagen type VI and tenascin was studied in biopsy specimens from the buccal mucosa of 19 Indian women with confirmed oral submucous fibrosis (OSF) using the immunogold-silver staining technique. Immunohistochemistry revealed a loss of stainable procollagen type III and collagen type VI in the fibrotic zones of oral submucous fibrosis compared to normal oral mucosa. Tenascin was noted only very faintly at the subepithelial basement membrane. The present study showed that procollagen type III and collagen type VI in OSF were expressed in a specific pattern which allows a clear differentiation between fibrotic areas and adjacent apparently normal connective tissue stroma. Loss of procollagen type III, and therefore a probable predominance of collagen type I in collagen fiber bundles, and an almost complete loss of collagen type VI might explain the stiffness of the oral mucosa in patients with OSF. The immunohistochemical findings provided evidence that the process of fibrosis starts in the deeper subepithelial connective tissue stroma and not close to the subepithelial basement membrane. Further studies are required to determine whether OSF is due to increased or altered synthesis and deposition of extracellular matrix proteins, altered fibrolysis or both.

Adult↗

In situ detection of PCR-amplified HIV-1 nucleic acids in lymph nodes and peripheral blood in patients with asymptomatic HIV-1 infection and advanced-stage AIDS.

This study determined the in situ detection rate of polymerase chain reaction (PCR)-amplified human immunodeficiency virus type 1 (HIV-1) DNA and RNA in lymph nodes and peripheral blood CD4+ cells in six patients with asymptomatic HIV-1 infection and from six people who died of advanced AIDS. The lymph nodes of patients with asymptomatic infection showed expanded germinal centers where, on average, 20% of the CD21+ dendritic cells contained HIV-1 DNA. From 5 to 80% of the CD4+ cells in these lymph nodes contained HIV-1 DNA, as compared with 1-11% of the CD4+ peripheral blood mononuclear cells. The infection in most cells was latent in the asymptomatic group. In contrast, the lymph nodes of patients with advanced AIDS showed marked depletion of both dendritic and CD4+ cells. The majority of the remaining CD4+ cells in the lymph nodes and blood showed PCR-amplified viral DNA and cDNA sequences suggesting the presence of genomic and multiple spliced transcripts. It is concluded that asymptomatic HIV-1 infection is associated with a wide range of latent to active viral-positive CD4+ lymphocytes and dendritic cells in the lymph nodes. Progression to AIDS is characterized by active viral replication in many of the remaining CD4+ cells in the lymph nodes and blood.

Acquired Immunodeficiency Syndrome↗

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↗