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Biomedical subjects

B Budowle

Publications and source records attributed to B Budowle.

At least 199 records · Page 11Linked to original sources

Hae III--a suitable restriction endonuclease for restriction fragment length polymorphism analysis of biological evidence samples.

Hae III has been selected by our laboratories as the restriction endonuclease of choice for restriction fragment length polymorphism analysis of forensic science samples. The enzyme is compatible with the D2S44 probe system and generates relatively small DNA fragments for that marker system. Similarly, Hae III is compatible with several other independent polymorphic loci, including D1S7, D4S139, D16S85, D17S74, D17S79, D14S13, and D20S15. Hae III is functional under a variety of adverse conditions for DNA digestion and is not affected by the methylation pattern in mammals. Finally, Hae III is a relatively inexpensive restriction endonuclease.

Base Sequence↗

Modifications to improve the effectiveness of restriction fragment length polymorphism typing.

A streamlined and effective method for RFLP analysis of DNA has been developed. Southern transfers are accomplished by alkali blotting DNA onto positively charged nylon membranes. The prehybridization step has been eliminated. The hybridization solution is composed of three cost-effective reagents: 7% SDS, 10% PEG, and phosphate buffer. By using probes that hybridize to variable number of tandem repeat loci, and RFLP analysis of one to two micrograms of genomic DNA can be achieved within five working days under normal working hours. With longer autoradiographic exposures, as little as 20-100 ng of human genomic DNA is sufficient for analysis.

Buffers↗

A simple and sensitive method for quantifying human genomic DNA in forensic specimen extracts.

The analysis of DNA restriction fragment length polymorphisms by Southern blot hybridization requires that sufficient quantities of high molecular weight genomic DNA be extracted from biological specimens. Prior to analysis, it is necessary to determine the quantity and quality of the extracted DNA. For many applications, it is also desirable to determine the amount of DNA which is of human origin. In this report, we describe a simple and highly sensitive procedure for the specific quantification of human genomic DNA in forensic extracts or any biological sample. A small fraction of the extract is immobilized onto a nylon membrane and subsequently hybridized to p17H8 (D17Z1), a cloned probe which detects highly repetitive, primate-specific alpha satellite DNA. The procedure requires less than four hours to complete and can be used to quantify subnanogram amounts of hybridizable human genomic DNA.

Blotting, Southern↗

Association of HLA-linked factor B with gestational diabetes mellitus in black women.

The factor B BfF allele was found significantly less frequently in nonobese black women with gestational diabetes mellitus than in the control group. The BfS allele was found more frequently, although not significantly so. These data suggest similar genetic associations among nonobese black women with gestational diabetes mellitus and those with insulin-dependent diabetes mellitus.

Alleles↗

An alternative, effective substrate for erythrocyte acid phosphatase phenotype determinations.

A method is described for obtaining nondiffusing, nonfading fluorogenic zymograms for erythrocyte acid phosphatase variants separated by isoelectric focusing. The synthetic substrate 4-trifluoromethylcoumarin phosphate was impregnated into cellulose diacetate membranes and air-dried overnight. After isoelectric focusing, the substrate overlay membrane was rehydrated in 0.05M citrate buffer, pH 4.0, lightly blotted, and overlayed on the gel. A 5- to 10-min incubation at 37 degrees C produced intensely fluorescing, light-blue bands on the diacetate membrane. Interaction of the trifluoromethyl group on the substrate with hydrophobic regions of the diacetate membrane impeded diffusion, yielding a permanent zymogram. There were no discrepancies in phenotype determinations using this method when compared with the 4-methylumbelliferyl phosphate assay approach. Further, an increased number of conclusive calls were obtained (91.8 versus 79.5% and 54.1 versus 34.9%) with this new assay when compared with the 4-methylumbelliferyl phosphate substrate on known liquid bloods and questioned dried bloodstains, respectively.

Acid Phosphatase↗

A hybrid ampholyte focusing technique for esterase D subtyping of evidentiary material.

An ultrathin-layer polyacrylamide gel isoelectric focusing technique that uses a composite of ampholytes from three commercial sources is described for subtyping esterase D. All common allelic products of esterase D were separated clearly. The technique described in this paper provides a higher conclusive call rate on known blood specimens (95.8%) and questioned bloodstains (69.7%) compared with continuous zone electrophoresis in agarose gels (89.9 and 37.6%, respectively).

Blood Stains↗

A method for subtyping group-specific component in bloodstains.

A method is described for subtyping group-specific component (Gc) derived from human bloodstains. Bloodstained cuttings were extracted in 6 M urea. The extracts were subjected to ultrathin-layer polyacrylamide gel isoelectric focusing in the pH 4.5-5.4 range. After isoelectric focusing, Gc was detected by immunofixation in cellulose acetate membranes. This method permitted the successful typing of Gc in at least four-month-old bloodstains maintained at room temperature. Bloodstains from 266 liquid blood samples of known origin were subjected to both this method and immunofixation conventional agarose gel electrophoresis with no phenotypic discrepancies observed. The Gc population data for Whites from Baltimore, Maryland, were homogeneous with white sample populations from other geographical locations within the U.S.A.; while Gc data from northern U.S.A. black sample populations appeared to be heterogeneous compared with a southern United States black sample population.

Actins↗

Glyoxalase I typing and phosphoglucomutase-1 subtyping of a single hair.

A technique is described for the typing of glyoxalase I (GLO I) and the subtyping of phosphoglucomutase-1 (PGM-1) from the root sheath cells of a single forcibly removed hair. This procedure does not require sample preparation and does not alter the morphological characteristics of the hair. The combined discrimination probability (DP) of the two markers taken together is 0.90 for whites and 0.89 for blacks. GLO I can be typed after four weeks, and PGM-1 can be typed after eight to fifteen weeks in hairs maintained at room temperature. Hairs mounted with Permount showed loss of enzyme activity and loss of band sharpness.

Forensic Medicine↗

Electrophoresis reliability: I. The contaminant issue.

The effects of the common contaminants--soil, oil, gasoline, salt, acid, base, bleach, and detergent--on various forensically used genetic marker systems were studied. The predicted effects of the various contaminants on the proteins and the electrophoretic separations agreed with the observed results. A contaminant that affected protein conformation also adversely affected the integrity of the electrophoretic system, thus signalling an anomaly. It also was pointed out that the ideal control study for the effects of contaminants on genetic markers in evidentiary material is often provided to forensic scientists--that is victim's blood on victim's clothing and other substrata. The data presented in this paper support the validity and reliability of electrophoretic analyses of evidentiary material with respect to the contaminant issue.

Blood Protein Electrophoresis↗

Ultrathin-layer polyacrylamide gel isoelectric focusing for the identification of hemoglobin variants.

An ultrathin-layer polyacrylamide gel isoelectric focusing method for typing hemoglobin is described. This method, which uses Pharmalyte pH 6.7-7.7 and an electrode wick distance of 5.0 cm, clearly resolves the A, F, S, C and a number of rare variant allelic products. The technique is ideal for rapid screening of a large number of fresh blood and/or bloodstained samples.

Blood Protein Electrophoresis↗

Applications of isoelectric focusing in forensic serology.

The typing of certain polymorphic proteins present in human body fluids is an important aspect of the analysis of serological evidence. This is particularly true when dealing with evidence related to violent criminal activity such as homocide, assault, or rape. Until recently, the routine analysis of the genetic polymorphisms of interest relied upon conventional electrophoretic techniques such as horizontal starch or agarose slab gel or both, cellulose acetate, and vertical polyacrylamide gradient gel methods. These techniques adequately separate a limited number of common variants. In some cases, these methods are still those of choice. However, as a result of the nature of the conventional approach, problems with time required for analysis, resolution, diffusion of bands, sensitivity of protein detection, and cost are often encountered. Isoelectric focusing (IEF) offers an effective alternative to conventional electrophoresis for genetic marker typing. This method exploits the isoelectric point of allelic products rather than charge-to-mass ratio in a particular pH environment. The advantages of employing IEF include: reduction of time of analysis, increased resolution of protein bands, the possibility of subtyping existing phenotypes, increased sensitivity of detection, the counteraction of diffusion effects, and reduced cost per sample.

Acid Phosphatase↗

Subtyping phosphoglucomutase-1 in semen stains and bloodstains: a report on the method.

A method is described for obtaining nondistorted, reproducible phosphoglucomutase-1 subtyping patterns from semen stains and bloodstains. Isoelectric focusing of phosphoglucomutase-1 was accomplished in 80 min in a 0.2-mm-thick polyacrylamide gel with an interelectrode wick distance of 8.0 cm. The gel contained 1.2% (w/v) N-(2-hydroxyethyl) piperazine-N-3-propanesulfonic acid (EPPS) and pH 5 to 7 ampholytes (4% w/v). When maintained at room temperature, laboratory-prepared bloodstains and semen stains could be typed for phosphoglucomutase-1 up to four months and three weeks, respectively. An evaluation of phosphoglucomutase-1 typing by isoelectric focusing and the Group I system was performed on casework samples submitted to the FBI Laboratory. In addition to the increased discriminating probability of phosphoglucomutase-1 when subtyped, isoelectric focusing yielded an increase in positive calls on questioned bloodstains (65.6 versus 36.2%) and dried seminal stains (16.4 versus 13.1%) compared with the Group I system.

Blood Stains↗

Genetic predisposition to acute lymphocytic leukemia in American blacks. A Pediatric Oncology Group study.

Recent reports have shown an association between genes lying within the major histocompatibility complex (MHC), particularly HLA and factor B (Bf), and acute lymphocytic leukemia (ALL) in white children. The frequencies of Bf and complement component C4 phenotypes in 90 black American children with ALL were examined to determine if a genetic association existed. The Bf and C4 results for the black children with ALL were compared with frequencies in healthy black Americans from the same geographic region. The BfF allele was carried by 95.6% of the black ALL patients compared with 86.1% of the controls (P = 0.017; relative risk = 3.5). In contrast, only 2.2% of the patients with ALL were homozygous for BfS compared with 9.8% of the controls (P = 0.043; relative risk = 0.2). These findings are similar to those observed in white American children. The C4A6 phenotype was found in 11.9% of the black children with ALL compared with 0.6% of the controls (P = 0.0026; relative risk = 22.7). These findings represent the first reported association of a particular allele whose gene lies within the MHC with ALL in black American children. The results suggest that the occurrence of ALL in black American children may be partially due to a genetic influence.

Adenosine Monophosphate↗

Transferrin subtyping of human bloodstains.

A method was described for subtyping transferrin derived from human bloodstains. Bloodstain cuttings were extracted in 0.5% ferrous ammonium sulfate. The extracts were subjected to ultrathin-layer polyacrylamide gel isoelectric focusing. After isoelectric focusing, transferrin was detected by silver staining. This method permitted the successful typing of Tf in 6-month-old blood stains maintained at -20 degrees C and room temperature and 3-month-old bloodstains maintained at 37 degrees C.

Blood Grouping and Crossmatching↗

An agarose gel electrophoretic method for typing phosphoglucomutase-1, esterase D, or glyoxalase I.

A conventional agarose gel electrophoretic method was described for typing phosphoglucomutase-1, esterase D, or glyoxalase I as single systems. Bloodstain extracts were absorbed into 1-mm-thick agarose gels via an application mask. The electrode wick distance was 12 cm and electrophoresis was carried out at 400 V at 6 degrees C. The electrophoretic run times were 30 min for glyoxalase and 1 h for esterase D or phosphoglucomutase. This method is reliable and produces highly resolved band patterns. Additionally, the shorter separation times as a result of the increased voltage gradient permitted typing of more samples in a given time period compared with presently used methods. This technique requires little technical expertise and can be incorporated into the laboratory at a minimal cost.

Blood Grouping and Crossmatching↗

Discontinuous polyacrylamide gel electrophoresis for typing haptoglobin in bloodstains.

A routine method is described for obtaining reproducible haptoglobin patterns from bloodstains by discontinuous polyacrylamide gel electrophoresis. By employing a stacking gel, proteins from bloodstain extracts are concentrated into narrow zones, before entering the resolving gel. This effect yields highly resolved haptoglobin patterns. Therefore, laboratories without the specialized equipment and expertise for polyacrylamide gradient gel preparation can still obtain highly resolved haptoglobin patterns from bloodstains.

Blood Grouping and Crossmatching↗

The complement component C4 in black Americans with type 1 (insulin-dependent) diabetes mellitus.

The complement component C4 variants C4A 4, C4B 4 and C4B Q0 were found to be significantly increased in 64 black patients with Type 1 (insulin-dependent) diabetes compared with 169 black control subjects, yielding relative risks of 3.3, 2.9 and 3.4, respectively. The increased frequencies of C4B 4 and C4B Q0 in black Type 1 diabetic patients are similar to those found in Caucasoid Type 1 diabetic patients. The data suggest that Type 1 diabetes in black Americans may be partially due to admixture of genes from whites.

Adult↗