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Biomedical subjects

K Sorensen

Publications and source records attributed to K Sorensen.

At least 55 records · Page 3Linked to original sources
PubMed1989

Detection and localization of human papillomavirus in penile condylomas and squamous cell carcinomas using in situ hybridization with biotinylated DNA viral probes.

Human papillomavirus (HPV) has been previously demonstrated in male genital neoplasms using Southern blot hybridization (SBH) and in situ hybridization with radiolabeled probes (ISH-R). In this study we used in situ hybridization with biotinylated DNA viral probes (ISH-B), a technique that can be applied to routinely collected and processed tissue. Thirty cases of exophytic penile condyloma acuminatum and nine cases of invasive squamous cell carcinoma of the penis were examined for the presence of HPV using ISH-B for HPV types 6, 11, 16, 18, 31, and 33. HPV DNA was found in 25 of 30 (83%) penile condylomas; HPV type 6 in 13 (43%); and HPV type 11 in 12 (40%). Slight cross-reactivity between HPV types 6 and 11 was noted. None of the condyloma cases was positive for HPV types 16, 18, 31, or 33. One of the nine patients with squamous cell carcinoma of the penis was positive for HPV 16. In situ hybridization with biotinylated DNA viral probes is a highly sensitive method for detecting and localizing HPV in penile condylomas. This method, however, may not be as sensitive as SBH for detecting HPV in invasive penile squamous cell carcinomas.

Adolescent↗
PubMed1988

An enzyme antigen immunoassay for the determination of neuron-specific enolase in serum samples.

A method is presented for the detection and quantification of neuron-specific enolase (NSE) in serum samples. It is an enzyme antigen immunoassay (EAIA), relying on specific antibodies to 'catch' the enzyme on a solid support (ELISA-plate) whereafter the enzymatic activity of the immunocaptured enzyme is determined, by coupling the reaction to lactate dehydrogenase. The oxidation of NADH to NAD is followed at 340 nm in an ELISA photometer. The method is proven to work well and is able to measure the low amounts of NSE present in serum samples from normal individuals. It does not require labelling of neither antigen nor antibody, and is therefore superior to the commercially available radioimmunoassay (RIA). The method will also work with monoclonal antibodies towards the enzyme as demonstrated by preliminary observations.

Animals↗
PubMed1987

Immunochemical determination of acetylcholinesterase in amniotic fluid--an evaluation of eleven monoclonal antibodies.

Eleven monoclonal antibodies and a polyclonal rabbit antiserum were evaluated with respect to reactivity with acetylcholinesterase (AChE, EC 3.1.1.7) from erythrocytes and brain. Employing our enzyme antigen immunoassay for AChE five selected antibodies were evaluated with regard to their clinical usefulness in the prenatal diagnosis of neural tube defects (NTD). Of these, one antibody preferentially bound the enzyme from human brain, and discerned better than the others pathological samples (anencephaly, spina bifida and encephalocele) from normal ones. With this antibody no false positive values were obtained even if amniotic fluid samples were blood contaminated.

Acetylcholinesterase↗
PubMed1987

An inhibitory monoclonal antibody to human acetylcholinesterases.

The monoclonal antibody AE-2 raised against acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7) from human erythrocytes is shown to inhibit the enzyme activity. The reaction of the antibody with a structural epitope is investigated further. The epitope resides on monomeric, dimeric and tetrameric species of the enzyme. The rate of phosphorylation of the enzyme by diisopropylfluorophosphate was not affected by the antibody. On the other hand, inhibitors directed towards the anionic site(s) competed with antibody binding, suggesting that one of these is the epitope. The titration with antibody is biphasic and yields about 80% inhibition even in the presence of a large excess of antibody. Inhibition is fully reversible upon dilution, in a time-dependent manner. AE-2 also inhibited human adult and fetal brain acetylcholinesterase (to the same extent). However bovine brain acetylcholinesterase was inhibited to a lesser extent and rat brain acetylcholinesterase did not interact with the antibody. Butyrylcholinesterase (EC 3.1.1.8) also showed no reactivity towards the antibody.

Acetylcholinesterase↗
PubMed1987

Fine-needle aspiration of fibromatosis of the breast.

Percutaneous fine-needle aspiration of breast fibromatosis yielded clusters of uniform spindle cells. The differential diagnosis of spindle stromal cells obtained by fine-needle aspiration of the breast is discussed. This includes a wide spectrum of both benign and malignant breast lesions that have to be considered prior to suggesting the diagnosis of fibromatosis.

Biopsy, Needle↗
PubMed1987

Determination of maternal serum acetylcholinesterase in pregnancies with fetal neural tube defects.

We have investigated the occurrence of acetylcholinesterase (AChE) (E.C. 3.1.1.7) in fetal serum, amniotic fluid and maternal serum using an immuno-chemical assay-technique employing both polyclonal and monoclonal antibodies. Fetal serum had increased amounts of AChE, which is due to an increase in the 10.5S form of the enzyme. This form was also found in amniotic fluids of pregnancies with a fetal neural tube defect (NTD), but not in normal amniotic fluid. The increase in amniotic fluid AChE was however, not reflected in the maternal serum.

Acetylcholinesterase↗
PubMed1987

Sarcoma of the uterine cervix: clinicopathologic findings in three cases.

The clinicopathologic findings in two patients with cervical stromal sarcoma and one with cervical leiomyosarcoma are presented. The patients were 35, 46, and 45 years, respectively. They presented with vaginal bleeding, vaginal discharge, and a cervical mass of less than 5 months duration. A hysterectomy with bilateral salpingo-oophorectomy was performed in each case. One patient received preoperative radiation therapy. Two patients with follow-up manifested hematogenous metastasis.

Adult↗
PubMed1987

Cyclosporine toxicity: the effect of combined therapy using cyclosporine, azathioprine, and prednisone.

Forty-nine patients among 360 who received renal transplants under cyclosporine (CsA)/prednisone (Pred) immunosuppression required alteration of the immunosuppressive regimen because of intractable nephrotoxicity. Twenty-five patients, converted totally to azathioprine (Aza)/Pred, suffered intractable nephrotoxicity with no associated evidence suggesting ongoing rejection. The results with Aza/Pred conversion were disappointing because of an unacceptably high incidence of rejection and allograft loss. Twenty-four patients with intractable CsA nephrotoxicity were, therefore, treated using an alternative approach combining Aza with aggressive CsA dose reduction, and continued Pred therapy. All patients tolerated initiation of Aza without complication; allograft rejection was not common. Renal function improved for 23 of the 24 (96%) CsA/Aza/Pred patients with mean serum creatinine levels falling from 3.5 +/- 0.5 mg/dL to 2.2 +/- 0.4 mg/dL after a mean follow-up of 14 months (P less than .001). Among 18 patients observed at least 12 months, seven (39%) enjoyed serum creatinine values less than or equal to 2 mg/dL. Nine CsA/Aza/Pred-treated patients (37.5%) required hospitalization because of infectious complications, all of which resolved with temporary reduction of immunosuppression and specific antimicrobial therapy when indicated. One patient sustained acute allograft rejection as a result of patient noncompliance, and one patient on a seemingly appropriate CsA/Aza/Pred dose responded initially to steroid pulse antirejection therapy; however, renal function again worsened. Two patients developed progressive renal dysfunction due to chronic rejection, and returned to dialysis 13 and 17 months, respectively, following initiation of CsA/Aza/Pred. Overall, the actuarial graft survival for CsA/Aza/Pred-treated patients was 100% at 1 year, and 84% at 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Assessment of coating-efficiency in ELISA plates by direct protein determination.

A commercially available protein determination method (Pierce BCA protein determination kit) was used to assess the efficiency of coating of microtiter plates. Since the method is insensitive to detergents it permits the determination of adhered protein after washing the microtiter plate with a detergent-containing solution. Thus only tightly bound protein is determined. Our results suggest that coating of microtiter plates with antibody is optimal at a certain concentration, above which coating is less efficient.

Animals↗
PubMed1986

Normal human serum contains two forms of acetylcholinesterase.

We have produced antibodies (polyclonal and monoclonal) against acetylcholinesterase, and used them for immuno-chemical demonstration and quantification of the enzyme in serum. The concentration was 1.2 IU/l. The antibodies were shown not to cross-react with human butyrylcholinesterase, using pure preparations of the enzymes. The serum acetylcholinesterase could be purified using affinity chromatography. The resulting preparation was analyzed using sucrose density gradient centrifugation. Two forms of the enzyme with sedimentation constants of 10.9S and 7.6S were observed, both reacted equally well with monoclonal antibodies towards acetylcholinesterase indicating a common epitope.

Acetylcholinesterase↗
PubMed1986

First report of Angiostrongylus cantonensis in Puerto Rico.

From January to April 1984, 63 Rattus rattus and 40 R. norvegicus were trapped in northeastern Puerto Rico and examined for Angiostrongylus cantonensis adults. Nineteen (47.5%) of the R. norvegicus and 10 (15.9%) of the R. rattus were infected, giving an overall infection rate of 28.2%. Four species of terrestrial snails and one species of brown slug were examined for A. cantonensis larvae. Two snail species, Subulina octona and Aquebana belutina, were found infected with third stage larvae of A. cantonensis. These larvae were harvested and inoculated per os into adult white mice. Immature adult worms were found in the brain tissue of all mice inoculated. This is the first report in the rat and snail populations of Puerto Rico.

Angiostrongylus↗
PubMed1985

Polymorphism and immunochemical cross-reactivity of acetylcholinesterases from the brains of human, dog, hog, bovine and horse.

In the caudate nucleus of the species tested about 20% of the acetylcholinesterase was salt soluble and sedimented in sucrose density gradient centrifugation as monomeric 5 S and tetrameric 10 S enzyme. About 80% was solubilized by micellar concentrations of Triton X-100 and sedimented as a tetrameric 10 S species in the presence of detergent but formed aggregates in the absence thereof. All the enzyme displayed poor cross-reactivity with a precipitating assay (Ouchterlony) but in a solid phase non-precipitating assay the cross-reactivity could be quantified and ranged from 96 to less than 1% depending on the species.

Acetylcholinesterase↗
PubMed1983

Senescent cell antigen is immunologically related to band 3.

IgG autoantibodies in human serum selectively bind to a glycopeptide antigen that appears on senescent and damaged cells in situ. We identified the membrane protein from which the senescent cell antigen is derived by using a phagocytosis-inhibition assay and immunoautoradiographic gel staining and electroblotting techniques. Results of the phagocytosis-inhibition assay revealed that only the purified transmembrane glycoprotein designated "band 3" and senescent cell antigen inhibited the phagocytosis of erythrocytes induced by IgG eluted from senescent erythrocytes. Purified spectrin, syndein, band 4.1, actin, glycophorin A, and intact or desialylated sialoglycoprotein periodic acid/Schiff (PAS) staining bands 1-4 containing glycophorins A, B, and C did not inhibit phagocytosis. Specific antibodies against the senescent cell antigen and erythrocyte band 3 were used to identify the membrane protein from which the senescent cell antigen is derived. Band 3-related polypeptides (MrS approximately equal to 60,000, 42,000, and 18-26,000) were identified in erythrocyte ghosts prepared in the presence of diisopropyl fluorophosphate, phenylmethylsulfonyl fluoride, and EDTA by immunoautoradiography with antiband 3. Antibodies to senescent cell antigen reacted with band 3 and the same lower Mr band 3-related polypeptides. Thus, the senescent cell antigen is immunologically related to band 3.

Anion Exchange Protein 1, Erythrocyte↗
PubMed1983

Clinical observations on virologically confirmed fatal dengue infections in Jakarta, Indonesia.

Thirty virologically confirmed cases of dengue infection with a fatal outcome were studied clinically in Jakarta, Indonesia, from 1975 to 1978. All 4 dengue virus serotypes were isolated from fatal cases, but dengue type 3 was responsible for 21 (70%) of these isolates, compared to only 47% of isolates from all cases of dengue infection. The majority (60%) of these 30 cases were males in the 5-9-year age group. Nonspecific signs and symptoms in the fatal cases were no different from those in patients who survived dengue infection, but 70% of the patients with fatal outcome had one or more signs of encephalitis, primarily convulsions and somnolence; 3 of them developed spastic tetraparesis before death and 2 died of an illness clinically compatible with viral encephalitis. Other unexpected observations were that only 63% of the patients had classical dengue shock syndrome with haemoconcentration, thrombocytopenia and shock. A high percentage (80%) had gastrointestinal haemorrhage, and in 9 patients (30%) this was severe enough to cause shock and death. In these 9 cases, the gastrointestinal haemorrhage and haematemesis began before the onset of shock and there was no evidence of haemoconcentration or pleural effusion at any time during hospitalization. According to certain widely accepted criteria, these patients would not be diagnosed as dengue haemorrhagic fever (DHF). But as they made up nearly one-third of the confirmed fatal dengue infections in this study and had massive gastrointestinal haemorrhages with thrombocytopenia, the definition of DHF should be changed to include this type of patient. It is proposed that the disease should be more realistically classified as dengue fever with or without haemorrhage and dengue shock syndrome.

Age Factors↗
PubMed1982

Antigenicity, storage, and aging: physiologic autoantibodies to cell membrane and serum proteins and the senescent cell antigen.

Normal human serum contains autoantibodies to a wide range of cellular and serum proteins. IgG autoantibodies to cell membrane proteins spectrin, syndein (Band 2.1), Band 3 degradation products, and the senescent cell antigen are among them. Physiologic autoantibodies to the senescent cell antigen, a approximately 62 000 dalton glycopeptide derived from Band 3, initiate removal of senescent, damaged, and stored cells in vivo. The senescent cell antigen is one of the two Band 3 degradation products (Mr approximately 66 000 and 62 000) observed in freshly prepared ghosts. Since the senescent cell antigen is observed on red cells aged in situ, data suggest that Band 3 undergoes proteolysis in situ. IgG eluted from blood stored for transfusion binds to the senescent cell antigen. The amount of IgG on red cells increases during storage suggesting accumulation of the senescent cell antigen. Autoantibodies to other cell and serum proteins are discussed as possible regulators of homeostasis. The effect of age on physiologic autoantibodies is reviewed.

Anion Exchange Protein 1, Erythrocyte↗