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Biomedical subjects

A Lewin

Publications and source records attributed to A Lewin.

At least 109 records · Page 6Linked to original sources
PubMed1986

Ultrasonically guided oocyte collection under local anesthesia: the first choice method for in vitro fertilization--a comparative study with laparoscopy.

Ultrasonically guided oocyte collection gradually replaces laparoscopy in many in vitro fertilization (IVF) centers. In the present study we compare the efficacy of both methods in our IVF program. One hundred twenty patients were prospectively randomized into two groups. Sixty women underwent oocyte collection during laparoscopy under general anesthesia, and 60 women under ultrasound guidance with local anesthesia. Superovulation was induced with human menopausal gonadotropin/human chorionic gonadotropin. For the oocyte collection a cannula with a trocar was used for single percutaneous puncture, through which both ovaries could be reached by the aspiration needle. The number of aspirated oocytes and transferred embryos was higher in the laparoscopy group as compared with the ultrasound group (5.3 versus 4.0 per woman and 3.0 versus 2.3 per woman, respectively); but the clinical pregnancy rate per cycle was similar in both groups (12.5% versus 14.5%). Ultrasound aspiration seems to be as effective as laparoscopy in terms of oocyte retrieval and conception rates. Because the procedure is simple and inexpensive, we believe that it may replace laparoscopy as a method for oocyte collection in most patients who undergo IVF.

Adult↗
PubMed1986

Identification of Rhizobium plasmid sequences involved in recognition of Psophocarpus, Vigna, and other legumes.

Symbiotic DNA sequences involved in nodulation by Rhizobium must include genes responsible for recognizing homologous hosts. We sought these genes by mobilizing the symbiotic plasmid of a broad host-range Rhizobium MPIK3030 (= NGR234) that can nodulate Glycine max, Psophocarpus tetragonolobus, Vigna unguiculata, etc., into two Nod- Rhizobium mutants as well as into Agrobacterium tumefaciens. Subsequently, cosmid clones of pMPIK3030a were mobilized into Nod+ Rhizobium that cannot nodulate the chosen hosts. Nodule development was monitored by examining the ultrastructure of nodules formed by the transconjugants. pMPIK3030a could complement Nod- and Nif- deletions in R. leguminosarum and R. meliloti as well as enable A. tumefaciens to nodulate. Three non-overlapping sets of cosmids were found that conferred upon a slow-growing Rhizobium species, as well as on R. loti and R. meliloti, the ability to nodulate Psophocarpus and Vigna, thus pointing to the existence of three sets of host-specificity genes. Recipients harboring these hsn regions had truly broadened host-range since they could nodulate both their original hosts as well as MPIK3030 hosts.

Base Sequence↗
PubMed1985

Comparative study of ultrasonically guided percutaneous aspiration with local anesthesia and laparoscopic aspiration of follicles in an in vitro fertilization program.

Twenty patients from our in vitro fertilization program were randomly divided into two groups. Ten women underwent follicular aspiration during laparoscopy while they were under general anesthesia and 10 women had an ultrasonically guided follicular aspiration with local anesthesia. All patients had mechanical infertility, and ovulation was induced with human menopausal gonadotropins. In both groups the same aspiration system with a needle of 1.4 mm inner diameter and a continuous suction at 120 mm Hg were used. In the laparoscopy group the oocyte recovery rate was 82.5% and the fertilization rate 62.5%, with one twin pregnancy; in the ultrasound group the oocyte recovery rate was 75%, and the fertilization rate 61.9%, with a singleton pregnancy. Implications of these results are discussed.

Adult↗
PubMed1985

Apparent prevalence of curable hypertension in the Hypertension Detection and Follow-up Program.

Data describing the 5,485 participants in the stepped-care group of the Hypertension Detection and Follow-up Program were reviewed to determine the apparent prevalence of renal parenchymal and reversible, secondary hypertension. The investigation was limited and was not designed to identify all cases of secondary hypertension. Baseline prevalence of proteinuria was 3.6%, pyuria 7.1%, hematuria 5.1%, and elevated serum creatinine level (greater than or equal to 1.7 mg/dL) 2.7%. The combined occurrence of an elevated serum creatinine level plus one or more urinary abnormalities was noted in 0.95%. Initial review of case reports revealed six participants with hypertension secondary to use of birth control pills and three participants with hypertension that was proved to be secondary to renovascular disease. Specific laboratory or historical criteria were used as indications for more intensive investigation in an additional 65 participants. Among these individuals, one participant with renovascular disease and three with possible primary hyperaldosteronism were identified. A rapid-sequence intravenous urogram or radionuclide scan was performed on another subgroup of 62 participants whose hypertension was "poorly" controlled (diastolic BP, greater than or equal to 95 mm Hg). Fifty-nine studies were negative, one was positive, and two were equivocal. These results suggest that the frequency of clinically relevant cases of reversible, secondary hypertension, at least among individuals with mild to moderate elevation of blood pressure, is low.

Adult↗
PubMed1980

Extraovular instillations of normal saline for termination of midtrimester pregnancy.

Midtrimester abortion by extraovular instillation of normal saline was performed in 50 patients. All 50 aborted following the procedure, and there were no complications except for one case of endometritis that was successfully treated by antibiotics. The mean abortion time was 33 hours, without added oxytocin, and 30 hours when pitocin was administered intravenously. The extraovular route eliminates the necessity for amniocentesis, with its associated risks. By using normal saline instead of pharmacologic agents such as urea, glucose, hypertonic saline, prostaglandins, we were able to eliminate the complications related to drug side effects.

Abortion, Induced↗
PubMed1980

Maternal pulmonary edema occurring after therapy with ritodrine for premature uterine contractions.

Intravenous administration of beta-sympathomimetic drugs in combination with betamethasone or dexamethasone is a treatment often used for the suppression of premature uterine contractions and for the stimulations of fetal lung maturity. It has been suggested that the combination of these drugs may be responsible for maternal pulmonary edema and five such cases have been reported in the literature (1,2). We report a patient who developed pulmonary edema during ritodrine therapy. Corticosteroids were not given in this case.

Adolescent↗
PubMed1980

Congenital adrenal hyperplasia diagnosed in a middle-aged woman.

Short stature, severe hirsutism, an enlarged clitoris and lack of vaginal introitus were manifest in a 55-year-old female karyotype, male phenotype patient brough up as a female. The hormone profile suggested congenital adrenal hyperplasia due to 21-hydroxylase adrenal enzyme deficiency. Follicle-stimulating hormone and luteinizing hormone levels were 122.5 and 100.3 mIU/ml, respectively, within the normal range for a postmenopausal woman. Computerized axial tomography revealed a large cystic tumor connected to the right adrenal gland. Both the right adrenal gland and the cyst were removed. The adrenal cortex showed diffuse hyperplasia and contained a well-defined nodule. The case was interesting because we had the opportunity of examining a patient of advanced age with untreated congenital adrenal hyperplasia and because of the very rare combination of adrenogenital syndrome with nodular hyperplasia and a cystic tumor, which was most probably a degenerated adenoma.

Adrenal Glands↗
PubMed1979

Propagation of restriction fragments from the mitochondrial DNA of Saccharomyces cerevisiae in E. coli by means of plasmid vectors.

Some of the EcoRI fragments of yeast (Saccharomyces cerevisiae) mitochondrial DNA were cloned into E. coli using plasmid pMB9. The five smallest fragments in molecular weight appeared to be preferentially retained by E coli; partial fragments derived from larger mitochondrial DNA fragments were also found. One of the fragments, R7 (2.4 kb), may contain the OII gene. Cloned R7 DNA was stable under a variety of growth conditions, but showed some changes in molecular weight after transfer to different E. coli strains. Fragment R7 is transcribed in minicells, producing RNA that hybridizes specifically to mitochondrial DNA. Both DNA strands are transcribed, in contrast to the asymmetric transcription found in mitochondria. No new polypeptides were observed in minicells containing cloned fragment 7.

DNA Restriction Enzymes↗
PubMed1978

Physical mapping of genes on yeast mitochondrial DNA: localization of antibiotic resistance loci, and rRNA and tRNA genes.

We have physically mapped the loci conferring resistance to antibiotics that inhibit mitochondrial protein synthesis (erythromycin, chloramphenicol and paromomycin) or respiration (oligomycin I and II), as well as the 21s and 14s rRNA and tRNA genes on the restriction map of the mitochondrial genome of the yeast Saccharomyces cerevisiae. The mitochondrial genes were localized by hybridization of labeled RNA probes to restriction fragments of grande (strain MH41-7B) mitochondrial DNA (mtDNA) generated by endonucleases EcoRI, HpaI, BamHI, HindIII, SalI, PstI and HhaI. We have derived the HhaI restriction fragment map of MH41-7B mit DNA, to be added to our previously reported maps for the six other endonucleases. The antibiotic resistance loci (antR) were mapped by hybridization of 3H-cRNA transcribed from single marker petite mtDNA's of low kinetic complexity to grande restriction fragments. We have chosen the single Sal I site as the origin of the circular physical map and have positioned the antibiotic loci as follows: C (99.5-1.Ou)--P (27-36.Ou)--OII (58.3-62u--OI (80-84u)--E (94.4-98.4u). The 21s rRNA is localized at 94.4-99.2u, and the 14s rRNA is positioned between 36.2-39.8u. The two rRNA species are separated by 36% of the genome. Total mitochondrial tRNA labeled with 125I hybridized primarily to two regions of the genome, at 99.5-11.5u and 34-44u. A third region of hybridization was occasionally detected at 70--76u, which probably corresponds to seryl and glutamyl tRNA genes, previously located to this region by petite deletion mapping.

Chloramphenicol↗
PubMed1978

Restriction enzyme analysis of mitochondrial DNAs of petite mutants of yeast: classification of petites, and deletion mapping of mitochondrial genes.

We have analyzed the restriction digest patterns of the mitochondrial DNA from 41 cytoplasmic petite strains of Saccharomyces cerevisiae, that have been extensively characterized with respect to genetic markers. Each mitochondrial DNA was digested with seven restriction endonucleases (EcoRI, HPaI, HindIII, BamHI, HhaI, SalI, and PstI) which together make 41 cuts in grande mitochondrial DNA and for which we have derived fragment maps. The petite mitochondrial DNAs were also analyzed with HpaII, HaeIII, and AluI, each of which makes more than 80 cleavages in grande mitochondrial DNA. On the basis of the restriction patterns observed (i.e., only one fragment migrating differently from grande for a single deletion, and more than one for multiple deletions) and by comparing petite and grande mitochondrial DNA restriction maps, the petite clones could be classified into two main groups: (1) petites representing a single deletion of grande mitochondrial DNA and (2) petites containing multiple deletions of the grande mitochondrial DNA resulting in rearranged sequences. Single deletion petites may retain a large portion of the grande mitochondrial genome or may be of low kinetic cimplexity. Many petites which are scored as single continuous deletions by genetic criteria were later demonstrated to be internally deleted by restriction endonuclease analysis. Heterogeneous sequences, manifested by the presence of sub-stoichiometric amounts of some restriction fragments, may accompany the single or multiple deletions. Single deletions with heterogeneous sequences remain useful for mapping if the low concentration sequences represent a subset of the stoichiometric bands. Using a group of petites which retain single continuous regions of the grande mitochondrial DNA, we have physically mapped antibiotic resistance and mit- markers to regions of the grande restriction map as follows: C (99.3--1.4 map units)--OXI-1 (2.5--15.7)--OXI-2 (18.5--25)--P (28.1--34.2)--OXI-3 (32.2--61.2--OII (60--62)--COB (64.6--80.8--0I (80.4--85.7)--E (95--98.9).

DNA Restriction Enzymes↗
PubMed1978

Combination chemotherapy followed by skin grafts in the management of locally advanced breast cancer.

A combined modality approach to the treatment of locally advanced, ulcerating carcinoma of the breast is discussed. The beneficial effects of combination chemotherapy have been amplified by split thickness skin grafts at the site of a large skin deficit, resulting in successful wound palliation. Criteria for assessing likelihood of graft acceptance by an ulcerating wound in the presence of local neoplastic disease are emphasized.

Breast↗