[Paratesticular liposarcoma: the clinicopathological features of nineteen cases]

Objective: To investigate the clinicopathological features and differential diagnoses of paratesticular liposarcoma. Methods: The cases were collected from 2012-2020, from the archives of the Department of Pathology, Peking University Third Hospital, with diagnosis confirmed by histology, immunostaining and FISH tests. Results: Totally 19 patients were enrolled (including 11 in-hospital patients and 8 consultant cases). The patients aged 37-84 years (mean 57 years). The preoperative clinical diagnoses were spermatic cord/inguinal masses (nine patients), scrotal masses (seven patients), and inguinal hernia (three patients). Six lesions recurred after local resection, including one case extending from pelvic liposarcoma. Histologically, there were 10 cases of well-differentiated liposarcoma (WDLPS) and nine cases of dedifferentiated liposarcoma (DDLPS). WDLPSs mostly showed the combined features of lipoma-like, inflammatory and sclerosing subtypes (six patients); the other four WDLPSs had pure lipoma-like subtype features. DDLPSs were low-grade (three patients) or high-grade (six patients), with the morphology resembling myxofibrosarcoma, inflammatory myofibroblastoma, spindle cell sarcoma, pleomorphic undifferentiated sarcoma and pleomorphic liposarcoma. Intense inflammatory cells infiltration was commonly observed in five WDLPSs and two DDLPSs. Ossification was observed in three tumors. Immunohistochemically, the tumors were positive for MDM2 (8/10) and CDK4 (10/10), which were expressed in lipo-differentiating cells, spindle cells in WDLPS, and in dediffferentiated components. S-100 was only expressed by lipocytes (10/10). CD34 expression was positive and diffuse in the stromal cells of WDLPSs and focal or diffuse in dedifferentiated areas (10/10). FISH tests with an MDM2 gene probe were positive (12/12). Conclusions: Paratesticular liposarcoma may be overlooked by both clinicians and pathologists. WDLPS and DDLPS predominate, showing various histologic divergences. The presence of amplification of the 12q14-q15 region (containing the MDM2 and CDK4 genes) is helpful for making the correct diagnosis.

Perceptions of urgency: defining the gap between what physicians and nurses perceive to be an urgent issue

INTRODUCTION

Through our research into the design and evaluation of technology systems to improve the quality and safety of clinical communication, we have discovered that physicians and nurses differ in perspective regarding clinical prioritization and desirable response times. This has a number of important consequences including unnecessary interruptions, escalating conflict and deterioration in interprofessional relationships. Understanding the differing perspectives on clinical prioritization, or the gap in perceived urgency, may improve interprofessional relationships.

METHODS

We conducted a mixed-methods study utilizing both qualitative (semi-structured interviews) and quantitative (surveys) methods to determine the gap between perceived urgency among physicians and nurses. The survey comprised of real messages extracted from the clinical communication system that was implemented. Physicians and nurses reviewed the messages and assigned an urgency level to each. The semi-structured interviews used open-ended questions to act as a guide to highlight key themes of interest. Thematic analysis, frequency tabulation, and triangulation were used to analyze the data.

RESULTS

Although the surveys demonstrated concordance between physicians and nurses when independently ranking the urgency of clinical messages (kappa=0.66 SE 0.15), agreement was only fair in comparison to the urgency identified by the original nurse who sent the message (kappa=0.22 SE 0.18). We hypothesize that clinical context has a major role in defining urgency and may explain this finding. The survey data was triangulated with the semi-structured interview data and it was determined that the desired response time significantly impacted the sender's message prioritization. For example, shift changes and anxious family members were associated with discordant prioritizations.

DISCUSSION

This study demonstrated that the perceived communication urgency gap between sending nurses and receiving physicians was primarily related to timeframe and context, not clinical condition. Most disagreement occurred when nurses used urgent messaging for time sensitive but not clinically urgent issues in an effort to expedite the resolution of their issue by the physicians. These results indicate the need for clinical communication systems to incorporate decision support around both clinical prioritization and expected response time in their design. Effective interprofessional communication is essential to the provision of safe, quality-based healthcare; these results highlight some of the sociotechnical aspects of health information technology implementation that must be considered.

Citosol (thiamylal sodium) triggers apoptosis and affects gene expressions of murine leukemia RAW 264.7 cells

Citosol (thiamylal sodium) is one of generally used anesthetic–sedative agents for clinical patients, and it has not been reported to show induction of cytotoxic effects in cancer cells, especially in mice leukemia RAW 264.7 cells in vitro. In the present study, we investigated the cytotoxic effects of citosol on mice leukemic RAW 264.7 cells, including the effects on protein and gene expression levels which are determined by Western blotting and DNA microarray methods, respectively. Results indicated that citosol induced cell morphological changes, cytotoxic effect, and induction of apoptosis in RAW 264.7 cells. Western blotting analysis demonstrated that citosol promoted the levels of Fas, cytochrome c, caspase 9 and 3 active form and Bax levels, but it suppressed Bcl-xl protein level that may lead to apoptotic death in RAW 264.7 cells. Furthermore, DNA microarray assay indicated that citosol significantly promoted the expression of 5 genes (Gm4884, Gm10883, Lce1c, Lrg1, and LOC100045878) and significantly inhibited the expression of 24 genes (Gm10679, Zfp617, LOC621831, Gm5929, Snord116, Gm3994, LOC380994, Gm5592, LOC380994, LOC280487, Gm4638, Tex24, A530064D06Rik, BC094916, EG668725, Gm189, Hist2h3c2, Gm8020, Snord115, Gm3079, Olfr198, Tdh, Snord115, and Olfr1249). Based on these observations, citosol induced cell apoptosis and influenced gene expression in mice leukemia RAW 264.7 cells in vitro.

Understanding interprofessional communication: a content analysis of email communications between doctors and nurses

BACKGROUND

Clinical communication is recognized as a major source of errors in hospitals. The lack of documentation of communication, especially among verbal interactions, often creates hindrances and impedes improvement efforts. By providing smartphones to residents and encouraging nurses to communicate with residents by email shifted much of the communication to emails which permitted analysis of content.

OBJECTIVE

Description on the interprofessional email communication between doctors and nurses occurring on the general internal medicine wards at two academic hospitals.

DESIGN

A prospective analysis of email communications between doctors and nurses.

SETTING

34 out of the 67 residents who were on the general medicine clinical teaching units consented to allow analysis of their emails over a 6 month period.

MAIN MEASURES

Statistical tabulations were performed on the volume and frequency of communications as well the response time of messages. Two physicians coded the content of randomly selected emails for urgency, emotion, language, type of interaction, and subject content.

KEY RESULTS

A total of 13,717 emails were available for analysis. Among the emails from nurses, 39.1% were requests for a call back, 18.9% were requests for a response by email and the remaining 42.0% indicated no response was required from physicians. For the messages requesting a response by email, only 50% received an email response. Email responses had a median response time of 2.3 minutes. Content analysis revealed that messages were predominantly non-urgent. The two most frequent purposes for communications were to convey information (91%) and to request action by the physician (36%).

CONCLUSIONS

A smartphone-based email system facilitated the description and content analysis of a large amount of email communication between physicians and nurses. Our findings provide a picture of the communication between physicians, nurses and other healthcare professionals. This work may help inform the further development of information and communications technology that can improve clinical communication.

Monitoring driver's alertness based on the driving performance estimation and the EEG power spectrum analysis

Preventing accidents caused by drowsiness behind the steering wheel is highly desirable but requires techniques for continuously estimating driver's abilities of perception, recognition and vehicle control abilities. This paper proposes methods for drowsiness estimation that combine the electroencephalogram (EEG) log subband power spectrum, correlation analysis, principal component analysis, and linear regression models to indirectly estimate driver's drowsiness level in a virtual-reality-based driving simulator. Results show that it is feasible to quantitatively monitor driver's alertness with concurrent changes in driving performance in a realistic driving simulator.

Mechanism of alpha-adrenergic regulation of expressed hKv4.3 currents

The transient outward potassium current (I(to)) is an important repolarizing current in the mammalian heart. I(to) is regulated by adrenergic stimulation; however, the effect of agonists on this current, and consequently the action potential duration and profile, is variable. An important source of the variability is the difference in the channel genes that underlie I(to). There are two subfamilies of candidate genes that are likely to encode I(to) in the mammalian heart: Kv4 and Kv1.4; the predominance of either gene is a function of the species, stage of development, and region of the heart. The existence of different isoforms of the Kv4 family (principally Kv4.2 or Kv4.3) further complicates the effect of alpha-adrenergic modulation of cardiac I(to). In the human ventricle, hKv4.3 is the predominant gene underlying I(to). Two splice variants of human Kv4.3 (hKv4.3) are present in the human ventricle; the longer splice variant contains a 19-amino acid insert in the COOH-terminus with a consensus protein kinase C (PKC) site. We used heterologous expression of hKv4.3 splice variants and studies of human ventricular myocytes to demonstrate that alpha-adrenergic modulation of I(to) occurs through a PKC signaling pathway and that only the long splice variant (hKv4.3-L) is modulated via this pathway. Only a single hKv4.3-L monomer in the tetrameric I(to) channel is required to confer sensitivity to phenylephrine (PE). Mutation of the PKC site in hKv4.3-L eliminates alpha-adrenergic modulation of the hKv4.3-encoded current. The similar, albeit less robust, modulation of human ventricular I(to) by PE suggests that hKv4.3-L is expressed in a functional form in the human heart.

Transcriptional activation of p21WAF1 by PTEN/MMAC1 tumor suppressor

The recently discovered tumor suppressor gene PTEN has been found mutated in many types of advanced tumors. When introduced into tumor cells that lack the wild-type allele of the gene, PTEN was able to suppress the growth of these cells. Here, we have analyzed how PTEN might alter cell cycle-regulatory controls to achieve this growth-inhibitory effect. We found that overexpression of PTEN stimulates the synthesis of three inhibitors of cyclin-dependent kinases, p21WAF1, p27KIP1, and p57KIP2. This effect is very specific, as the expression of other components of the cell cycle engine, various cyclins and cyclin-dependent kinases, is not affected. For p21WAF1 we show that this induction is due to the p53-independent transcriptional activation of its promoter. In addition, increased expression of PTEN rendered the cells more sensitive to apoptotic cell death. Therefore, our data suggest a two-fold mechanism of growth inhibition by PTEN: one that acts via the increased expression of CKIs such as p21WAF1, and another that augments the cellular propensity for apoptotic cell death.

Role of p53 in aziridinylbenzoquinone-induced p21waf1 expression

Quinones are the second largest family of anticancer drugs clinically used in the United States. However, their exact mode of action at the cellular and molecular level is not completely understood. We have shown earlier that the quinone 3,6-diaziridinyl-1,4-benzoquinone (DZQ) leads to the increased expression of p21waf1/cip1/sdi1 protein, an inhibitor of cyclin-dependent kinases. Because p21 has been established as an important negative regulator of the cell cycle, we further investigated the molecular basis of p21 induction by DZQ. Here we report that the induction of p21 by DZQ is regulated at the transcriptional level, and requires the activation of p53, a tumor suppressor protein. In cells that lack functional p53 protein, DZQ-mediated p21 induction is greatly diminished. However, the introduction of a wild type p53 gene into p53-negative cells restores the strong DZQ-inducibility of p21. Restoration of wild type p53 status in HL60 myeloid leukemia cells significantly increases the cells' sensitivity to the cytotoxic effects of DZQ. Thus, our results indicate that the p53-p21 pathway may play a central role in mediating the gene-regulatory and cytotoxic effects of aziridinylbenzoquinones.

Activation of p53-p21waf1 pathway in response to disruption of cell-matrix interactions

The proliferation of most cells is strictly dependent on cell-matrix interactions, a phenomenon called anchorage dependence. Because tumor cells often are independent of this regulation, it is important to characterize the molecular pathways that control cellular proliferation after detachment of cells from their matrix. In this report, we investigated a possible role of p53 and one of its target genes, p21(waf1/cip1), as components of anchorage-dependent cell growth control. We found that p53 protein is rapidly activated upon the disruption of cellular attachment. This led to p21 transcriptional activation via two p53-binding sites in its promoter. Elevated p21 protein levels blocked transcription and activity of the cell cycle-regulator cyclin A, and cells became arrested in G1 of the cell cycle. Under the same conditions, fibroblasts from p53 knock-out mice did not activate p21 and did not down-regulate cyclin A expression but rather induced another cell cycle inhibitor, p27. Thus, our results characterize a chain of events, starting from the activation of p53 and proceeding via p21 to cyclin A, that is activated in response to the loss of cellular adherence. This p53-regulated pathway may constitute one of a few redundant systems to ensure proper cell control in multicellular organisms.

The 3' untranslated region of coronavirus RNA is required for subgenomic mRNA transcription from a defective interfering RNA

The 3'-end of mouse hepatitis virus (MHV) genomic RNA contains a recognition sequence (55 nucleotides [nt]) required for minus-strand RNA synthesis. To determine whether the 3'-end sequence is also involved in subgenomic mRNA transcription, we have constructed MHV defective interfering (DI) RNAs which contain a chloramphenicol acetyltransferase (CAT) gene placed behind an intergenic sequence and a 3'-end sequence with various degrees of internal deletions. The DI RNAs were transfected into MHV-infected cells, and CAT activities, which represent subgenomic mRNA transcription from the intergenic site, were determined. The results demonstrated that the deletions of sequence upstream of the 350 nt at the 3'-end, which include the 3'-untranslated region (3'-UTR), of MHV genomic RNA did not affect subgenomic mRNA transcription. However, deletions that reduced the 3'-end sequences to 270 nt or less completely abolished the mRNA transcription despite the fact that all of these clones synthesized minus-strand RNAs. These results indicated that mRNA transcription from an intergenic site in the MHV DI RNA requires most of the 3'-UTR as a cis-acting signal, which likely exerts its effects during plus-strand RNA synthesis. A substitution of the corresponding bovine coronavirus sequence for the MHV sequence within nt 270 to 305 from the 3'-end abrogated the CAT gene expression, suggesting a very rigid sequence requirement in this region. The deletion of a putative pseudoknot structure within the 3'-UTR also abolished the CAT gene expression. These findings suggest that the 3'-UTR may interact with the other RNA regulatory elements to regulate mRNA transcription.

Application of natural and amplification-created restriction sites in prenatal and preimplantation diagnosis of beta-thalassemia

We attempted the strategy of natural and amplification-created restriction sites for early prenatal and preimplantation diagnosis of Chinese beta-thalassemia. Mutagenesis primers were designed for 11 mutations reported for the Chinese population. The diagnosis was established after polymerase chain reaction and digestion of products by specific enzymes. The results were confirmed by direct sequencing of enzymatically amplified double-stranded DNA. The beta-globin gene was amplified from triploid embryos and isolated blastomeres using mismatched primers. The mutant and normal alleles can be distinguished clearly by this new method. Early prenatal diagnosis was successfully achieved in 9 cases. The beta-globin gene was successfully amplified from single blastomeres and tripronuclear embryos with mismatched primers. Natural and amplification-created restriction sites are a reliable method for rapid prenatal diagnosis of beta-thalassemia. Furthermore, the strategy provides a possible approach for the preimplantation diagnosis of beta-thalassemia.

Detection of Y-chromosome sequences in patients with X-chromosome abnormalities

The polymerase chain reaction was used to test 18 adults and eight fetuses with numerical or structural X-chromosome abnormalities for the presence of nine Y-specific loci. Y-chromosomal DNA was detectable in one adult patient with X-chromosome mosaicism. This study and previous reports provide evidence to support further screening of patients with X-chromosome abnormalities for the presence of Y-chromosomal DNA sequences. Long-term follow-up of patients with Y-chromosomal sequences is required to determine the risk of gonadal neoplasms and other abnormal phenotypes.

Detection of Y-chromosomal DNA with marker chromosomes in Turner's syndrome

Patients with clinical features of Turner's syndrome may have a 45,X/46,X + mar or 46,X + mar karyotype. It is estimated that phenotypic females or intersexuals with a Y chromosome and gonadal dysgenesis have a 20% risk of developing gonadoblastoma, so it is crucial to know whether Turner's syndrome patients have a Y chromosome. We studied the chromosomal make-up of four patients with Turner's syndrome using the polymerase chain reaction (PCR). Nine Y-chromosomal loci including four loci (PABY, SRY, ZFY, DYS14) on the short arm, one loci (DYZ3) on the centromere, and four loci (DYS132, DYS1, DYZ1, DYZ2) on the long arm were amplified to determine the origin of marker chromosomes. Three patients were identified as having Y chromosome DNA. Patient 1 contained the presumed gonadoblastoma locus (DYS132) and a prophylactic gonadectomy was carried out. DNA extracted from dysgenetic gonads did not show Y chromosome DNA. A rapid, highly sensitive and isotope-free method for detection of abnormal Y chromosomes in Turner's syndrome patients has been developed. Chromosome in situ hybridization analysis is required to confirm the PCR results, to provide further evidence for molecular organization of these marker chromosomes.

Prenatal ultrasonographic diagnosis of congenital megalourethra

Congenital megalourethra is a rare genital anomaly characterized by dilatation of the penile urethra without evidence of distal obstruction. Reports of the prenatal diagnosis of this condition in the literature are limited. We present a case of congenital megalourethra with obstructive uropathy from the posterior urethra diagnosed prenatally at 18 weeks of gestation. 'Prune-belly'-like features, colonic malrotation, and imperforate anus were also found on autopsy.

Characterization of 5'-upstream sequence of the latent membrane protein 1 (LMP-1) gene of an Epstein-Barr virus identified in nasopharyngeal carcinoma tissues

Sequence variations of the 5'-upstream region of latent membrane protein 1 (LMP-1) in two Epstein-Barr virus (EBV) strains have been reported before (Chen et al., 1992). To investigate the effect of these variations on gene expression, we constructed a series of deletion plasmids encompassing positions -950 to +20 of the LMP-1 promoter region and tested for the ability to drive chloramphenicol acetyltransferase (CAT) gene expression in C33A cells. Results showed that the promoter activities of constructs from NPC strain were 3-fold lower than the corresponding constructs from the B95-8 strain. In addition, the region between -54 and +20 contained the basic, constitutive promoter activity for both strains. Sequence analysis of this region indicated that an activating transcription factor (ATF) binding site, TGACGTAG, which is present in B95-8 strain was changed to TCTCGTAG in NPC strain. A chimeric plasmid study suggested that these sequence variations in the ATF binding site may contribute to the 3-fold increase of CAT activity observed for B95-8 strain. Furthermore, the activity of the promoter constructs was not activated by EBV-encoded nuclear antigen 2 (EBNA-2) in C33A cells. However, the promoter activities were upregulated in B-lymphocyte cells such as CG3 and CA46 cells. The biological significance of this difference in promoter activity of LMP-1 gene between two strains and the involvement of the cellular factors were discussed.

Spontaneous resolution of fetal mediastinal cystic hygroma

We present a case of prenatally diagnosed mediastinal cystic hygroma with spontaneous resolution. To our knowledge, this is only the second case report of mediastinal cystic hygroma diagnosed prenatally, and the first one with spontaneous resolution perinatally. Our case shows that, in the absence of hydrops fetalis, mediastinal cystic hygroma in a fetus with normal karyotype can be associated with a normal outcome. Therefore we recommend fetal karyotyping, a careful search for other anomalies and close sonographic follow-up in such cases.

Carrier screening and prenatal diagnosis for alpha-thalassemia with biphasic polymerase chain reaction

Alpha-thalassemia is the most common single gene disorder in Taiwan and Southeast China. The majority of alpha-thalassemic mutations in this area are alpha-thalassemia 1. Homozygous alpha-thalassemia 1 has been recognized as the most important cause of hydrops fetalis. To investigate the incidence of alpha-thalassemia 1 mutations and to characterize its molecular defects, cord blood electrophoresis was performed on 2,000 newborns, of which 99 (5%) cases were found to have hemoglobin (Hb) Bart's levels > 3.0%. A methodology using biphasic polymerase chain reaction (PCR) with nesting primers was developed to characterize the alpha-thalassemia 1 Southeast Asia type (SEA) deletion in the cases with detectable Hb Bart's levels. The SEA deletion was found in 92 (93%) of 99 cases. Prenatal screening was performed on couples with abnormal hematologic indices, and PCR was used to detect couples heterozygous for SEA deletion. Prenatal diagnosis was performed in 21 cases, and four cases were found to have a homozygous SEA deletion. This strategy can be applied to couples who need prenatal genetic counseling for alpha-thalassemia major in this area.

Prenatal diagnosis of dicephalic conjoined twins: report of a case

Dicephalus is one of the rarest types of conjoined twins. In such cases, the twins are usually stillborn or die shortly after birth. Termination of the pregnancy is recommended if conjoined twins are diagnosed early in the second trimester. A case of dicephalic conjoined twins with cystic hygroma diagnosed prenatally by ultrasound at 16 weeks' gestation is presented. The ultrasonographic findings, management and pathology are discussed.

Amplification of beta-globin gene from single blastomeres

Prenatal diagnosis of beta-thalassemia can be performed by chorionic villus sampling as early as the ninth gestational week, and early amniocentesis within 12 weeks of gestation. Selective abortion or termination should be suggested if the fetus is affected. With polymerase chain reaction (PCR) and micromanipulation techniques, the preimplantation diagnosis of beta-thalassemia has become possible. A total of 60 single blastomeres were collected and equally divided at random into two groups. Eight DNA primers (A to H) were designed for 15 mutations of beta-thalassemia in Chinese people. Two beta-globin gene fragments (602 bp and 423 bp) were amplified by PCR through two sequential reactions with two sets of primers (A+B and C+D, E+F and G+H), respectively. The amplified products were confirmed by Southern blotting with DNA probes hybridization. The amplification rates were 54% (16/30) and 60% (18/30), respectively. All of the positive and negative controls showed the presence or absence of amplification, respectively. Our study provides a possible approach for the preimplantation diagnosis of beta-thalassemia.

X chromosome mosaicism in patients with recurrent abortion or premature ovarian failure

X chromosome mosaicism is usually associated with abnormal sexual development and reproductive performance, such as recurrent spontaneous abortion, primary or secondary amenorrhea, infertility, and premature ovarian failure. However, there is a paucity of literature which discusses these relationships. From July 1988 to December 1992, a total of 105 couples with a history of recurrent spontaneous abortion from a genetic counseling clinic and 61 women with a history of premature ovarian failure followed up in reproductive endocrinology clinics were assembled, and chromosomal analysis of peripheral blood lymphocytes was carried out. X chromosome mosaicism was found in six individuals (2.9%) out of the 105 couples with recurrent spontaneous abortion, and in five (8.2%) out of 61 women with premature ovarian failure. The karyotypes were 45,X/46,XX/47,XXX in five cases, 45,X/46,X in four cases, and 46,XX/47,XXX in two cases. The cases of complex X chromosome mosaicism (45,X/46,XX/47,XXX) presented recurrent spontaneous abortion in four cases and premature ovarian failure in one case. The cases of mosaic Turner's syndrome (45,X/46,XX) presented premature ovarian failure in three cases and recurrent spontaneous abortion in one case. The two cases of mosaic triple-X syndrome (46,XX/47,XXX) presented with premature ovarian failure and recurrent spontaneous abortion, respectively. However, the ratio of mosaic cell lines does not correlate well with the phenotypic manifestations in our cases. Our preliminary data suggest that chromosomal analysis should be done routinely in every couple with recurrent spontaneous abortion and in women with premature ovarian failure. The reproductive performance of X chromosome mosaicism is highly variable and difficult to define.(ABSTRACT TRUNCATED AT 250 WORDS)

Tubal embryo transfer for the treatment of infertility

The outcome of treatment for male factor infertility with either gamete intrafallopian transfer (GIFT) or in vitro fertilization and embryo transfer (IVF/ET) has been unsatisfactory. A better approach may be tubal embryo transfer (TET). In our medical center, from November 1989 to December 1990, 80 couples (male factor, n = 35, non-male factor, n = 45) entered our program for TET. Superovulation was conducted with either human menopausal gonadotropins (hMG) or gonadotropin-releasing hormone agonist (GnRH-a, buserelin)/hMG. Ovum retrieval (OR) was possible in 73 patients and successful fertilization after insemination occurred in 64 of them. TET was performed only when there was at least one grade III-V embryo. The mean number of embryos transferred was 3.92 +/- 0.13 (range 1-5). There were 35 pregnancies out of 55 TET (64% per TET, 48% per OR). In the group with male factor infertility, OR occurred in 32, and 24 achieved fertilization. Ten pregnancies were achieved after 19 TET (53% per TET, 31% per OR). In comparison, the group with non-male factor infertility had a higher pregnancy rate (69% per TET and 61% per OR). There have been 15 live births, 14 ongoing pregnancies (eight sets of twins and 21 singletons), five abortions and one ectopic pregnancy. Our results indicate that: 1) TET is a valuable treatment for non-tubal factor infertility; and 2) in the group with male factor infertility, it has the advantages of demonstrating fertilization in vitro and preventing unrewarding laparoscopies.

Different isozymes of mouse 11 beta-hydroxylase produce mineralocorticoids and glucocorticoids

We have isolated and characterized two isozymes of mouse steroid 11 beta-hydroxylase (11 beta-OHase), designated 11 beta-OHase and aldosterone synthase (AS). Physical mapping of overlapping cosmid and phage isolates defined two genes (designated Cyp11b-1 and Cyp11b-2 in the standard nomenclature for cytochrome P450 genes) that are oriented in the same direction and separated by approximately 8 kilobase pairs of DNA. The two genes are highly homologous in their coding regions, with 84% nucleotide identity and 86% predicted amino acid identity. In regions where the sequences of the rat 11 beta-OHase and AS genes diverged most widely, the mouse sequences also differed significantly, thereby identifying putative mouse 11 beta-OHase and AS genes. Both genes were mapped to chromosome 15 by analyzing restriction fragment length variations in a panel of DNA samples from an interspecific cross. To determine the functional properties of the 11 beta-OHase and AS proteins, we transfected COS-7 cells with plasmids that expressed the proteins encoded by the 11 beta-OHase and AS genes. When expressed in transfected COS-7 cells, the 11 beta-OHase protein converted deoxycorticosterone to corticosterone but did not produce aldosterone. Consistent with its postulated role in mineralocorticoid biosynthesis, the product of the AS gene efficiently synthesized aldosterone. We next studied the expression of these two isozymes in Y1 adrenocortical tumor cells and in the intact mouse adrenal gland. Although Y1 cells otherwise resemble zona fasciculata cells and express the 11 beta-OHase gene at high levels, transcripts encoded by the AS gene were detected at levels approximately 10-fold lower than the 11 beta-OHase transcripts.(ABSTRACT TRUNCATED AT 250 WORDS)