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S Lenz

Publications and source records attributed to S Lenz.

At least 37 records · Page 2Linked to original sources

Benchmarking: finding ways to improve.

BACKGROUND: This article provides health care organizations with a benchmarking methodology to use in comparing practices and processes to identify and actualize opportunities for improvement. The 15-step model can be used to guide internal and external benchmarking activities in a variety of health care settings. EXAMPLES: Two internal benchmarking case studies are illustrated: (1) one hospital used the Baxter model to evaluate its laparoscopic cholecystectomy services, and (2) another prepared for expansion of cardiac catheterization services. CONCLUSIONS: Two key factors of a successful benchmarking initiative are highlighted: management commitment and involvement, and the need to understand internal practices and processes before benchmarking.

Cholecystectomy, Laparoscopic↗

Ultrasonic texture and volume of testicles in infertile men.

Ultrasound scanning of the testes and surgical biopsy were performed in 95 infertile men to evaluate the use of ultrasound in male infertility. Ultrasonic testicular volume was calculated using three measurements and the formula of an ellipsoid, and the ultrasonic texture was evaluated and given a score from 1 to 5, indicating increasing degrees of irregularity. The median score was 3 (range 1-5), which was higher than previously found in normal men (median score 2; range 1-5; P < 0.0001). The ultrasonic texture score was lower in testes with a uniform pattern of 100% spermatogenic tubules compared with the rest, both for the right (P < 0.001) and for the left (P < 0.0005) testis. Texture score was correlated with the number of obliterated tubules for both testes (P < 0.001). The mean ultrasonic testicular volume of the right testis was 10.30 ml, and that of the left 10.26 ml. Both were smaller compared with the findings in normal men (P < 0.0001). Ultrasonic testicular volume was negatively correlated with texture score (P < 0.001). A positive correlation between ultrasonic volume and sperm count was seen (P < 0.001). Sperm count was negatively correlated with texture score if calculated together with data from 119 men from the general population (P < 0.001). The study shows that ultrasonic volume and texture are valuable parameters in the evaluation of infertile men.

Adult↗

Ultrasonic testicular texture and size in 444 men from the general population: correlation to semen quality.

Scrotal ultrasonography was performed in 888 testes of 444 randomly selected men appearing before the medical board prior to military service (Mili group, 287 men, median age 18.8 years), and in employees from an industrial company (Empl group, 157 men, median age 35.6 years). The ultrasonic volume of each testis was calculated from 3 perpendicular measurements. The ultrasonic texture on sectional planes was scored using a scale from 1 to 5, 1 being very regular, 2 slightly irregular, 3 moderately irregular, 4 very irregular or with bright echogenic points, and 5 with demarcated tumor suspicious areas. Orchidometer measurements were performed in 258 men in Mili group, and semen samples were obtained from 121 men in Empl group. The ultrasonic volume of the right testis (median 14.1 ml, range 3.0-31.4 ml) was bigger than that of the left testis (median 13.0 ml, range 3.5-35.2). The volume was dependent on age for men under 20 years, but not for men aged 20 years or more. The subgroup of men with a history of cryptorchidism had a smaller average testicular volume (median 10.5 ml) compared with men with normal descent (median 14.1 ml). Ultrasonic volume was positively correlated to the total sperm count in the ejaculate, to sperm penetration in egg white, and to normal sperm morphology. The echo score distribution showed slightly higher scores in Empl for both the right and the left testis. Men in Empl group were older, and it could not be precluded that this difference was due to age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Quality indicators: control maintains--propriety improves.

Continuous improvement of care depends upon the efforts of all nursing personnel. Supervisors facilitate quality program operations in their specific areas; head nurses document outcomes; and staff nurses identify problems and contribute to planning. All join in evaluating appropriateness of patient care and in modifying approaches for greater effectiveness.

Hospital Bed Capacity, 500 and over↗

Gamete intrauterine transfer.

Gamete intrauterine transfer has been performed at a very limited scale until now. The main target group of patients for such a treatment would be women with infertility due to the tubal factor, but other infertile patients could benefit also, as the procedures reduce incubation time in the laboratory and implies fertilization in vivo. Few studies have been reported from 1982 to 1990 on the transfer of oocytes and spermatozoa directly to the uterus, and only five clinical pregnancies have been achieved. Transfer of oocytes and spermatozoa inside a biodegradable capsule has only been performed in one study comprising 26 cycles with no ensuing pregnancies. A critical evaluation and a status is carried out.

Embryo Transfer↗

Intrauterine capsules for incubation of gametes and subsequent release of embryos.

In order to obtain incubation in uteri of spermatozoa, oocytes, and embryos, for treatment of patients referred for in vitro fertilization, a capsule was produced which could contain the human gametes and allow human fertilization and embryo growth after intrauterine introduction. Agar was chosen for capsule material and a mold was constructed for the production of capsules. The material was tested in vitro using mouse embryos and human oocytes and sperm. Intrauterine resolution was tested on mice and by insertion on 11 women. Empty capsules were inserted into the uterine cavity in 15 cycles the day after the luteinizing hormone peak and followed by daily ultrasound examinations. The resolution time was adjusted by changing the wall thickness of the capsules. The final type was dissolved after 3 to 4 days. No complications were observed and capsules could be inserted on all occasions. The major problem was expelling of capsules, which occurred in seven cycles. The problem seemed to be solved by the administration of indomethacin at the day of insertion.

Adult↗

Intrauterine fertilization capsules--a clinical trial.

Treatment of 26 women with tubal infertility was attempted using intrauterine capsules loaded with oocytes and spermatozoa. The stimulation protocol was as used for in vitro fertilization and embryo transfer and consisted of short-term use of Buserelin, human menopausal gonadotropin, and human chorionic gonadotropin. Oocytes were collected by ultrasonically guided transvaginal aspiration, and spermatozoa were prepared by swim-up technique. The gametes were placed in agar capsules 4 hr after oocyte collection, and the capsules were introduced to the uterine fundus using an insertion tube and piston from an intrauterine device. Six complete capsules and parts of two other capsules were expelled. None of the women became pregnant, compared with a pregnancy rate of 21% per aspiration following in vitro fertilization and embryo transfer during the same period.

Buserelin↗

Cancer of the testicle diagnosed by ultrasound and the ultrasonic appearance of the contralateral testicle.

Fifty-six patients admitted for surgery due to suspicion of testicular cancer were randomly selected for preoperative ultrasound scanning. The result of scanning was compared with the diagnosis obtained at surgery and subsequent microscopy. Thirty-one patients had testicular cancer which in all cases had been detected by ultrasound. In patients suffering from benign diseases a tumor of the testis was seen (1 patient) or suspected (3 patients) in 4 patients. Two of these patients had an infection of the testis, and one had the testis removed as a tumor was suspected also at surgery. The diagnostic specificity of a visualised or suspected testicular tumor seen by ultrasound was 89%, and the diagnostic sensitivity was 100%. The echo pattern of testicular tissue adjacent to testis tumors was very irregular, with a score 4 in all tumor using a score from 1 (regular) to 5 (tumor pattern). The echo pattern of the contralateral testicles was more irregular (mean score 3.3) in tumor patients compared with the echo pattern in patients suffering from benign diseases (mean score 2.7).

Humans↗

Ultrasonic evaluation of endometrial growth in women with normal cycles during spontaneous and stimulated cycles.

Ultrasound scanning of the endometrium was performed through the menstrual cycle in normal, ovulating women in 20 unstimulated cycles (A), 13 clomiphene citrate (CC)/human menopausal gonadotrophin (HMG)/human chorionic gonadotrophin (HCG)-stimulated cycles (B) and 20 CC/HMG/HCG-stimulated cycles with oocyte collection (C). A total of 294 endometrial scans were performed and the texture and thickness of the endometrium registered. All data were related to the day of the luteinizing hormone (LH) peak or to HCG administration (day 0). There was no difference between groups in the image of the endometrium, which consisted of thin echogenic lines from day -10 until day 0 (99%). Three thin echogenic lines were seen in the pre-ovulatory endometrium in all cycles. During the luteal phase, confluent, thick echogenic lines were observed in all but two cycles, where the pre-ovulatory pattern persisted. The endometrium reached a mean thickness at days -1 to +1 of 6.4 mm in group A and 6.1 mm in groups B and C together. The endometrium was thinner at days -7 to -5 and -4 to -2 in groups B and C together (2.7 mm and 4.2 mm) compared with group A (4.6 mm and 5.8 mm) despite increased serum levels of oestradiol. At days +2 to +4, the endometrium was thicker in groups B and C together (7.2 mm) compared with group A (5.3 mm).

Chorionic Gonadotropin↗

A comparison of vaginal ultrasonic-guided and laparoscopic retrieval of oocytes for in vitro fertilization.

A retrospective analysis was undertaken to compare the less invasive technique of vaginal ultrasonic-guided oocyte retrieval with the standard laparoscopic technique. We have shown that the outcome of the transvaginal technique with respect to oocytes harvested, fertilization rate, and pregnancy rate is comparable with the laparoscopy technique. We have also shown that 9 clinicians with little previous expertise in ultrasound have been able to incorporate this technique into a busy and successful in vitro fertilization unit.

Female↗

The alkali light chains of human smooth and nonmuscle myosins are encoded by a single gene. Tissue-specific expression by alternative splicing pathways.

Human smooth muscle and nonmuscle cells express closely related myosin alkali light chains which are different from the isoforms present in striated muscle tissues. To date no information on the amino acid sequence of these mammalian nonstriated muscle isoforms has been available. We have isolated full-length cDNA clones encoding the nonmuscle (lym4) and smooth muscle (GT6) myosin light chains (MLCs) from cultured human lymphoblasts and heart aorta smooth muscle cells, respectively. Here we present the complete nucleotide sequences for both cDNA clones, together with the deduced amino acid sequences for the peptides. Both cDNAs contain the same open reading frame for 151 amino acids with 5 amino acid differences located in the C terminus. These differences are encoded by a block of 44 nucleotides which is present only in the smooth muscle (SM) mRNA. To identify the human gene coding for the two MLC isoforms, we have isolated and sequenced the nonmuscle (NM)/SM MLC gene, together with several intronless pseudogenes. A single functional gene was found containing 7 exons which are utilized for the coding information of the SM MLC mRNA. In contrast, the NM MLC mRNA does not contain sequences encoded by exon 6 which corresponds to the 44 nucleotides expressed in SM mRNA. This genomic configuration suggests that both the smooth muscle and nonmuscle MLCs in man are generated from the identical primary transcript by alternative splicing pathways taking place in a tissue-dependent manner.

Amino Acid Sequence↗

Alkali myosin light chains in man are encoded by a multigene family that includes the adult skeletal muscle, the embryonic or atrial, and nonsarcomeric isoforms.

A set of cDNA clones coding for alkali myosin light chains (AMLC) was isolated from fetal human skeletal muscle. Nucleotide sequence analysis and RNA expression patterns of individual clones revealed related sequences corresponding to (i) fast fiber type MLC1 and MLC3; (ii) the embryonic MLC that is also expressed in fetal ventricle and adult atrium (MLCemb); and (iii) a nonsarcomeric MLC isoform that is found in all nonmuscle cell types and smooth muscle. The AMLC gene family in man comprises unique copies for MLC1, MLC3 and MLCemb, and multiple copies for the nonsarcomeric MLC genes. The gene coding for MLC1 and MLC3 is located on human chromosome 2.

Amino Acid Sequence↗

Ovarian cysts in women with inflammatory bowel disease.

The frequency of ovarian cysts in patients with Crohn's disease (CD) or ulcerative colitis (UC) is believed to be higher than in the normal population, but this aspect has not been studied hitherto. The prevalence of ovarian cysts in the normal population is unknown. By ultrasonic scanning, we studied the frequency of ovarian cysts in 61 patients with CD, 64 with UC, and in 100 controls. The findings were positive in 3 out of 61 with CD, 5 of 64 with UC, and in 2 of 100 controls. There is a tendency to a higher frequency of ovarian cysts in patients with inflammatory bowel diseases than in the normal population, but no statistically significant difference.

Adult↗

Obstetric behavior and ultrasonic uterine characteristics of oligomenorrheic women.

Two groups of age-, parity-, and pregnancy-matched women, viz. 78 with oligomenorrhea (A) and 78 with normal menstrual intervals (B), plus all women with regular menstruation but in whom severe Müllerian malformations had been diagnosed during the same period (C) were followed in a prospective study to detect complications, sonographic changes, and the serum oxytocinase concentration during pregnancy and labor. Among the matched groups A and B, ultrasonic scanning revealed uterine changes in 45% and 9%, respectively (p less than 0.0005) during the 2nd trimester. Among the oligomenorrheic women who had HSG, fairly mild Müllerian malformations were found in 40%. The sonographic method in these mild and moderate anomalies had its limitations, and the findings were interpreted in several cases as fibroma or contractions. Complications occurred in 51% of the group A women who carried their pregnancies to term versus 20% in group B (p less than 0.0005). Among the primiparae the complication rates were 47% and 22%, respectively (p less than 0.025). Bleeding in early pregnancy (25%), an unstable fetal lie (28%), malpresentations (14%), and premature contractions or delivery (11%) were more common in group A (p less than 0.05-0.01). On stratification of the oligomenorrheic group without or with Müllerian anomalies (A1 and A2) the overall complication rates were 55% and 73%, respectively, and 86% in group C. Mutually, these differences are not statistically different, but all differ significantly from the control group (B) (p less than 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Life-threatening hemorrhage due to uterine vascular abnormality.

A case is reported of a 25-year-old woman stricken with prolonged and life-threatening menorrhagia from abnormal uterine vessels resembling hemangioma cavernosum. The condition was suspected at ultrasonic investigation. Hysterectomy was performed as an emergency operation.

Adult↗