Search PubMed⌕ Search

Biomedical subjects

R Greenspan

Publications and source records attributed to R Greenspan.

14 recordsLinked to original sources
PubMed2001

Improvements in pathologic staging for African-American men undergoing radical retropubic prostatectomy during the prostate specific antigen era: implications for screening a high-risk group for prostate carcinoma.

BACKGROUND: The objective was to compare the changes in pathologic and clinical data over time for African-American (AA) and white men with prostate carcinoma undergoing radical prostatectomy in an attempt to determine the early impact of prostate specific antigen (PSA). METHODS: Data from 195 AA and 587 white men who underwent radical prostatectomy from 1988 to 1999 in an equal access, tertiary, military medical facility were collected. Statistical analysis was used to determine the significance of the changes in the rates of extracapsular extension (ECE), positive margins, pretreatment PSA levels, and age at the time of surgery for each race over time. RESULTS: Comparing 1988-99 results, the authors found that the percentage of AA men with ECE decreased from 100% to 34.8% (P = 0.007), and for white men from 56.9% to 43.2% (P = 0.269). The percentage of AA men with positive margins decreased from 100% to 26.1% (P < 0.0001), and for white men from 41.2% to 27.0% (P = 0.021). Mean age at surgery decreased from 66.6 to 59.9 years for AA men (P < 0.001) and from 65.9 to 61.1 years for white men (P < 0.001). Also, PSA levels decreased from 10.1 to 6.6 ng/dL for white men (P < 0.001) and from 16.5 to 6.5 ng/dL for AA men (P < 0.001). CONCLUSIONS: The authors believe that the decrease in ECE and positive margins in AA men is primarily because of PSA testing, coupled with improved public awareness and equal access to care. It appears reasonable to recommend PSA testing in AA men, who have historically experienced poor outcomes from prostate carcinoma.

Adult↗
PubMed1999

Computerized bone densitometric analysis: operator-dependent errors.

PURPOSE: To determine the nature and relative frequency of operator-dependent data analysis errors in dual x-ray absorptiometry. MATERIALS AND METHODS: Over 40 months, 2,528 dual x-ray absorptiometric examinations of the forearm, femoral neck, and lumbar spine were performed by 11 technologists by using standard techniques and software. Each analysis was reviewed by a radiologist; errors were recorded and corrected. RESULTS: There were no forearm analysis errors. There were 24 (0.9%) femoral neck analysis errors, of which 23 resulted from misplacement of the analysis region. There were 33 (1.3%) spinal analysis errors, of which 24 resulted from misplacement of intervertebral disk space markers. Analysis errors of the femur and spine resulted in six misdiagnoses (0.2%). CONCLUSION: Misdiagnosis due to analysis errors is rare. Femoral neck analysis errors were easily detectable, but accurate spinal analyses depended on accurate identification of vertebral end plates and posterior elements. Nonetheless, these potentially serious errors can be detected and corrected if the analyses are reviewed and interpreted by a supervising physician who is familiar with the relevant anatomy, proper analysis techniques, and factors--such as artifacts--that adversely affect the accuracy of the analysis.

Absorptiometry, Photon↗
PubMed1998

Regulation of cell-type specific expression of lacZ by the 5'-flanking region of mouse GAD67 gene in the central nervous system of transgenic mice.

The transcriptional regulation of the murine gene encoding the 67-kDa form of glutamic acid decarboxylase (GAD67) was studied by beta-galactosidase histochemistry in transgenic mice carrying fusion genes between progressively longer portions of the 5'-upstream regulatory region of GAD67 and E. coli lacZ. No expression was detected in brains of mice carrying 1.3 kb of upstream sequences including a housekeeping and two conventional promoters, and two negative regulatory elements with homology to known silencers. In mice carrying the same portion of the promoter region plus the first intron, lacZ expression in the adult central nervous system was found in few, exclusively neuronal sites. The number of correctly stained GABAergic centres increased dramatically with increasing the length of the 5'-upstream region included in the construct which suggests that multiple putative spatial enhancers are located in this region. Their action is influenced by epigenetic mechanisms that may be due to site-of-integration and transgene copy-number effects. Additional cis-acting elements are needed to obtain fully correct expression in all GABAergic neurons of the adult central nervous system.

Animals↗
PubMed1994

Distinct protein forms are produced from alternatively spliced bicistronic glutamic acid decarboxylase mRNAs during development.

It has been shown that the enzyme glutamic acid decarboxylase (GAD; EC 4.1.1.15), which catalyzes the conversion of L-glutamate to gamma-aminobutyric acid in the central nervous system of vertebrates, can be first detected in rodents at late embryonic stages. In contrast, we have found that the gene coding for the 67-kDa form of GAD is already transcriptionally active at embryonic day E10.5 in the mouse. In addition to the 3.5-kb adult-type mRNA, we have detected two 2-kb embryonic messages that contain alternatively spliced exons of 80 (I-80) and 86 (I-86) bp, respectively. The overlapping stop-start codon TGATG, found in the embryonic exons, converts the monocistronic adult-type transcript into a bicistronic one, coding for a 25-kDa leader peptide and a 44-kDa enzymatically active truncated GAD. A second stop codon at the 3' end of the 86-bp exon abolishes the expression of truncated GAD. The products of the two embryonic mRNAs were identified in a rabbit reticulocyte in vitro translation system, COS cells, and mouse embryos. The two GAD embryonic forms represent distinct functional domains and display characteristic developmental patterns, consistent with a possible role in the formation of the gamma-aminobutyric acid-ergic inhibitory synapses.

Alternative Splicing↗
PubMed1989

Knowledge about AIDS and self-reported behaviour among Zimbabwean secondary school pupils.

Knowledge about AIDS and self-reported sexual behaviour was studied among 1532 (893 male, 633 female) Zimbabwean secondary school pupils drawn from 12 schools. Most subjects knew that AIDS is fatal and incurable. However, over 40% of subjects believed that most people with AIDS in Africa are homosexual. Over 40% of respondents did not know that many HIV seropositive individuals look healthy. Nearly 40% of participants believed that HIV can be contracted from toilet seats and 54% of subjects believed that mosquitos can transmit HIV. Pupils from homes in urban areas were better informed about AIDS than were those from homes in rural areas. Forty-six percent of males and nearly 3% of females were reportedly sexually experienced. It is suggested that female under-reporting of sexual activity occurred. Nearly 16% of males reported coital experience with a prostitute. The implications of these findings for future AIDS awareness campaigns in Zimbabwe are considered.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Knowledge about AIDS among Zimbabwean teacher-trainees before and during the public awareness campaign.

Knowledge about AIDS was studied among 4,189 Zimbabwean teacher-trainees from January to March, 1988, about six months after a national AIDS awareness campaign began. Knowledge about AIDS among part of this sample of teacher-trainees surveyed after the AIDS campaign began was also compared with that displayed by 630 teacher-trainees studied in January, 1987, roughly six months before the AIDS campaign began. Over 85 percent of 1988 subjects knew that AIDS is fatal and incurable. More than 80 percent of 1988 respondents knew that a condom is an effective precaution against AIDS. However, among 1988 participants, 35 percent did not know that many people carrying the AIDS virus look healthy, 36 percent believed that many AIDS victims in Africa are homosexual, 36 percent did not know that one cannot contract AIDS from a toilet seat, 40 percent believed that kissing transmits AIDS and nearly half believed that mosquitoes transmit AIDS. Males and subjects from urban homes were better informed about AIDS than females and those from rural homes, respectively. Teacher-trainees surveyed in 1988 were generally more knowledgeable about AIDS than those studied in 1987. The implications of these results for further educational efforts are considered.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Radiographic findings in the esophagus following the Sugiura procedure.

Sixteen patients underwent a modification of the Sugiura procedure for bleeding esophageal varices, involving (a) esophageal transection, (b) splenectomy, (c) selective vagotomy, and (d) pyloroplasty. Five patients died, and the remaining 11 had barium studies of the esophagus and stomach which were compared with the preoperative appearance. Esophageal varices disappeared in 7 patients and persisted in 1. No recurrent bleeding or encephalopathy was seen: however, there were a large number of complications, including pleural effusion, ascites, ileus, pneumonia, and renal failure. Hepatic failure, respiratory failure, and sepsis secondary to gastrointestinal leakage also occurred and were fatal in all cases. As the Sugiura procedure is increasingly being employed in the United States, radiologists should be familiar with the spectrum of postoperative radiographic findings in the esophagus and stomach.

Adult↗
PubMedDate not supplied

Delayed hemolytic transfusion reaction caused by the second example of anti-K19.

A second example of anti-K19 has been identified in the serum of a black patient immunized by blood transfusions. The antibody was responsible for delayed hemolysis of transfused incompatible red blood cells. The patient's red blood cells are K:--19 but are otherwise of common Kell phenotype. The K19 antigen is closely associated with the Kell blood group although there is, as yet, no pedigree information to confirm that it is produced by the Kell gene. Tests on 10,757 group O blood donors have not revealed any further examples of the K:--19 phenotype.

Anemia, Hemolytic, Autoimmune↗