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J Sklar

Publications and source records attributed to J Sklar.

140 records · Page 8Linked to original sources
PubMed1975

Determination of genes, restriction sites, and DNA sequences surrounding the 6S RNA template of bacteriophage lambda.

A major product of the transcription of bacteriophage lambda DNA in vitro is the 6S RNA. This article presents a detailed mapping of restriction endonuclease cleavage sites about the region of the 6S RNA template within the lambda genome. Restriction fragments defined by these sites have been used to localize the 6S RNA template within the physical and genetic maps of the lambda genome. Nucleotide sequence analysis of one of these fragments has largely confimed the nucleotide sequence of the 6S RNA reported previously and has indicated the sequence of DNA that immediately follows the 6S RNA template. This article reports the nucleotide sequence following a known site of transcription termination by RNA polymerase of Escherichia coli.

Base Sequence↗
PubMed1974

Abortion, illegitimacy, and the American birth rate.

In sum, it appears that legal abortion depressed overall fertility, but particularly illegitimate fertility, by giving women an opportunity to terminate their pregnancies when other means of birth control either had not been used or had failed. If legalized abortion had not been available, an estimated additional 39,000 illegitimate babies and 28,000 legitimate babies would have been born in 1971 in the United States. While this makes up a small part of total births (3,500,000), the illegitimate births prevented represent almost onetenth of all out-of-wedlock children born in the country in that year. In addition to preventing these births the legalization of abortion appears to have reduced the incidence of pregnancy-related marriages and thereby may have helped to limit subsequent marital disruption. Finally, legal abortion prevented large numbers of illegal abortions from occurring. Our data indicate that well over half-most likely between two-thirds and three-fourths-of all legal abortions in the United States in 1971 were replacements for illegal abortions. Further declines in illegitimate birth rates for the country as a whole will depend, in considerable part, on the extent to which legal abortion becomes more readily available and more widely used. Theoretically, greater use of efficient contraception could also cause illegitimate fertility to decline. But there are many reasons why women do not use efficient contraception even when they know about it and have access to the materials (25). Even though the use of abortion throughout the nation is now legalized by the Supreme Court decision, this does not necessarily mean that services will in fact be everywhere more readily available. Our interstate analysis suggests that should the liberalization of abortion laws be reversed, not only would there be an upturn in illegal abortions and pregnancy-related marriages, but also a marked rise in illegitimacy, particularly among women who do not have the means to obtain an illegal abortion.

Abortion, Legal↗
PubMed1974

The 5'-terminal nucleotide sequence of galactose messenger ribonucleic acid of Escherichia coli.

The 5'-terminal sequence of mRNA from the galactose operon of E. coli has been determined. gal RNA is synthesized in vitro by means of a kinetically controlled purified transcription system and is isolated by a two-step RNA.DNA hybridization scheme. The following sequence of the first 77 nucleotides has been deduced by analysis of oligonucleotides produced by digestion with T(1), pancreatic, and carboxymethylated pancreatic ribonucleases: ppA-U-A-C-C-A-U-A-A-G-C-C-U-A-A-U-G-G-A-G-C-G-A-A-U-U-A-U-G-A-G-A-G-U-U-C-U-G-G-U-U-A-C-C-G-G-U-G-G-U-A-G-C-G-G-U-U-A-C-A-U-U-G-G-A-A-G-U-C-A-U-A-C-C-U-G-U. Residues 27-77 correspond to the amino terminal 17 amino acids of UDPgalactose 4-epimerase (EC 5.1.3.2), the protein specified by the promoter-proximal structural gene of the operon. A self-complementary sequence occurs near the 5' terminus; 12 of 15 nucleotides between residues 4 and 18 are symmetrically located about position 11. The sequence of residues 22-33 closely resembles part of the lactose operator sequence reported previously [Gilbert, W. & Maxam, A. (1973) Proc. Nat. Acad. Sci. USA 70, 3581-3584].

Amino Acid Sequence↗
PubMedDate not supplied

Clonal antigen receptor gene rearrangements and Epstein-Barr viral DNA in tissues of Hodgkin's disease.

In an initial survey of 16 cases of Hodgkin's disease, tissues from one case of nodular sclerosing Hodgkin's disease, a recurrence with numerous Reed-Sternberg cells, demonstrated faint heavy- and light-chain immunoglobulin gene rearrangements. Analysis of seven additional similar cases with extremely numerous Reed-Sternberg cells revealed that six of these seven cases contained clonally rearranged heavy- or light-chain genes. In addition, the original biopsy specimen from the index case (obtained two years prior to the recurrence) had the same pattern of rearrangements of the immunoglobulin genes. In contrast, a germline configuration was observed for the beta T cell receptor gene in all cases. These cases of Hodgkin's disease were also investigated for the presence of Epstein-Barr viral (EBV) genomes by Southern and slot-blot DNA hybridization analysis. Tissues from four of the 21 case studied showed evidence of EBV DNA sequences. Uninvolved lymphoid tissue from two of the positive cases failed to demonstrate viral DNA. To assess clonality of the cells containing the EBV genomes, the tissues positive for EBV DNA were also hybridized with a restriction fragment probe for the terminal sequences of the EBV genome. By this analysis three of the four cases demonstrated a clonal population of EBV-infected cells.

DNA, Viral↗
PubMedDate not supplied

Patterns of meniscal injury with acute anterior cruciate ligament tears.

One hundred two patients underwent an arthrotomy for the primary repair of an acute ACL tear with or without an associated collateral ligament injury. The mean age was 23 years. Forty-seven patients (46%) had meniscal injuries. Meniscal injuries were found in 41% of Group I patients (isolated ACL injuries) and in 54% of Group II patients (injured ACL/collateral ligaments). Twenty-eight medial and 22 lateral meniscal tears were noted. Twenty-six of the 50 meniscal tears (52%) were sutured in an attempt to repair the menisci. Of these, 20 of the medial (71%), and 6 of the lateral (27%) meniscal injuries were sutured. No patients in this series required a total meniscectomy. A thorough evaluation of the menisci is mandatory in knees with an acutely injured ACL.

Adolescent↗
PubMedDate not supplied

An epidemiologic study of sports and weight lifting as possible risk factors for herniated lumbar and cervical discs. The Northeast Collaborative Group on Low Back Pain.

The associations between participation in several specific sports, use of free weights, and use of weight lifting equipment and herniated lumbar or cervical intervertebral discs were examined in a case-control epidemiologic study. Specific sports considered were baseball or softball, golf, bowling, swimming, diving, jogging, aerobics, and racquet sports. Included in the final analysis were 287 patients with lumbar disc herniation and 63 patients with cervical disc herniation, each matched by sex, source of care, and decade of age to 1 control who was free of disc herniation and other conditions of the back or neck. Results indicated that most sports are not associated with an increased risk of herniation, and may be protective. Relative risk estimates for the association between individual sports and lumbar or cervical herniation were generally less than or close to 1.0. There was, however, a weak positive association between bowling and herniation at both the lumbar and cervical regions of the spine. Use of weight lifting equipment was not associated with herniated lumbar or cervical disc, but a possible association was indicated between use of free weights and risk of cervical herniation (relative risk, 1.87; 95% confidence interval, 0.74 to 4.74).

Adult↗
PubMedDate not supplied

High dose cyclophosphamide plus recombinant human granulocyte-colony stimulating factor (rhG-CSF) in the treatment of follicular, low grade non-Hodgkin's lymphoma: CALGB 9150.

The main objectives of this study were to determine the feasibility of administering high doses of cyclophosphamide plus recombinant human granulocyte-colony stimulating factor (rhG-CSF) every 14-21 days to patients with follicular small cleaved cell lymphoma. For each patient, the treatment was not considered feasible if fewer than four cycles of cyclophosphamide chemotherapy could be administered on schedule (i.e. at least every 29 days) or (1) hospitalization of the patient for longer than three days was necessary for neutropenic fever (38 degrees C) or bacteriologically documented infection in > 50% of the cycles, or (2) grade > or = 2 hemorrhage in association with thrombocytopenia of grade > or = 3 severity occurred in > 50% of the cycles or (3) non-hematologic toxicity (excluding nausea/vomiting and alopecia) of grade > or = 3 occurred in > 50% of cycles. The goal was to have a treatment program feasible in 75% or more of the treated patients. The secondary objectives were to determine the toxicities, the complete and partial response rates, and the time to treatment failure (TTF). The trial also attempted to assess the effectiveness of this treatment program in eradicating Bcl-2 rearrangements by PCR, and to assess complete remission duration in relationship to PCR results in patients who respond to this chemotherapy program. Patients were required to have histologically documented non-Hodgkin's lymphoma of the subtypes follicular, predominantly small cleaved cell (IWF-B) or follicular mixed, (IWF-C). Patients were required to have Stage IV disease including histologic evidence of bone marrow involvement. Measurable disease was required and patients were also required to have one of the following risk factors: > or = 2 extranodal sites, node or nodal group > or = 5 cm. Submission of fresh bone marrow for molecular genetic studies for the presence of Bcl-2-Ig fusion DNA was mandatory in previously untreated patients. Patients had to be between 18 and physiologic age 55 years (carefully selected patients over age 55 years were also eligible), expected survival > 2 years, performance status 0-1, and have adequate renal, hepatic and bone marrow function, and a cardiac ejection fraction > or = 50%. Cyclophosphamide 4.5 g/m2 i.v. was given with mesna every 14 days with rhG-CSF support. Twenty-nine patients were accrued to this trial. The median follow-up time is 5.0 years, with a range of 2.5-6.7 years. The overall response rate was 75% (9 CRs 37.5%, 9PRs 37.5%). The median duration of survival is 5.53 years. The 1-year estimated probability of freedom from treatment failure was 50% and of survival at 1 year was 92%. No strong association was observed between TTF and age, symptomatic stage, histology performance status, number of extranodal sites or baseline Bcl-2 status. At 3 years the survival of all patients was 78% and failure free survival was 17%. 15 (62%) of the 24 eligible previously untreated patients met the criteria for feasibility specified in the protocol. The 95% CI for the feasibility rate is (44 and 82%). Twenty-two of the 24 (92%) previously untreated patients had specimens submitted for testing for Bcl-2 rearrangements. Thirteen of the 22 (59%) were found to have rearrangements at baseline. Post-treatment specimens were submitted for seven of the 13 patients. Four of the seven converted to Bcl-2 negative following treatment. Eight of 13 Bcl-2 positive patients (62%) had a clinical response to treatment. The 95% exact binomial CI for the total response rate in this subgroup is (28 and 88%). This study demonstrates that repetitive doses of cyclophosphamide at 4.5 g/m2 every two weeks with rhG-CSF support can be administered to selected younger patients with advanced follicular lymphoma with morphologic involvement of the bone marrow with acceptable non-hematologic toxicity.

Adult↗