Two new species of Duplicibothrium Williams & Campbell, 1978 (Tetraphyllidea: Serendipidae) from the Pacific cownose ray Rhinoptera steindachneri.

Two new tetraphyllidean species, Duplicihothrium caircae n. sp. and D. paulum n. sp., are described from Pacific cownose rays Rhinoptera steindachneri collected from the Gulf of California. D. cairae n. sp. differs from the only other known species in this genus, D. minutum, in its possession of two posteriorly bifurcating longitudinal septa on each bothridium and having a greater number of loculi per bothridium, wider bothridia and a greater number of segments per worm. D. paulum n. sp. differs from the above two species in being shorter, having two continuous longitudinal septa on each bothridium, rather than posteriorly bifurcating or absent longitudinal septa, having a greater number of loculi per bothridium and having fewer segments per worm. The generic diagnosis of Duplicibothrium is amended to reflect the inclusion of the two new species. Species of Duplicibothrium appear to be restricted to host species of the genus Rhinoptera. Systematic information gained from the study of these two new species supports the monophyly of the tetraphyllidean family Serendipidae and suggests that Duplicibothrium shares a phylogenetic heritage with species in the genera Glyphobothrium and Serendip, taxa that are also parasitic in cownose rays. Evidence for a phylogenetic relationship between serendipid species and species of Dioecotaenia is discussed, as are potential molluscan hosts for cestode species in Duplicibothrium and Dioecotaenia.

Transvaginal ultrasonographic measurement of endometrial thickness in postmenopausal women receiving estrogen replacement therapy.

OBJECTIVE: This study was undertaken to evaluate endometrial thickness by transvaginal ultrasonography in asymptomatic postmenopausal women receiving estrogen replacement therapy. The endometrial thickness in this study group was compared with endometrial thickness measurements in a group of women who had abnormal postmenopausal bleeding. The recent literature was reviewed. STUDY DESIGN: Asymptomatic postmenopausal women receiving estrogen replacement, seen for routine examination during the 1-year period from Jan. 1, 1994, to Dec. 31, 1995, had the endometrium evaluated by transvaginal ultrasonography. Women with abnormal postmenopausal bleeding were likewise evaluated and their measurements compared with those of the study group. RESULTS: Twenty-seven different estrogen and estrogen-progestin combinations in 327 asymptomatic women were studied. Additionally, 24 women who were bleeding, not receiving estrogen, and 46 women with abnormal bleeding on estrogen therapy underwent ultrasonography of the endometrium. Endometrial thickness ranged from 1 to 15 mm in women on a regimen of combined estrogen-progestin therapy, 1 to 14 mm in women using sequential estrogen-progestin, and 3 to 15 mm for women receiving unopposed estrogen in the study group. For women with abnormal bleeding not using estrogen, the endometrium measured an average of 12.3 mm (range 2 to 29 mm), with unopposed estrogen 8.3 mm (range 4 to 13 mm), and for estrogen with progestin 6.5 mm (range 2 to 15 mm). Significant pathologic features were found in those women who had bleeding and endometrial measurements between 5.0 and 29 mm. CONCLUSION: There was no significant difference between endometrial thickness measurements in women receiving various combinations of estrogen replacement. In general, expected endometrial measurements can range from 1 to 15 mm. In women with postmenopausal bleeding, however, significant pathologic features may exist with an endometrium measuring as little as 5 mm.

Hensen's node regulates avian neural crest differentiation in vitro.

Different anteroposterior (AP) regions of the neural crest normally produce different cell types, both in vivo and in vitro. AP differences in neural crest cell fates appear to be specified in part by mechanisms that act prior to neural crest cell migration. We, therefore, examined the possibility that the fates of neural crest cells, like those of neural tube cells, can be regulated by interactions with Hensen's node. Using a transfilter co-culture system, we found that young (stage 3+ to 4) Hensen's node up-regulates the expression of two cranial-specific phenotypes (fibronectin and smooth muscle actin immunoreactivities) in mass cultures of trunk neural crest cells, and down-regulates the expression of a trunk-specific phenotype (melanin synthesis). The changes in phenotype produced by exposure to young Hensen's node were not accompanied by changes in the proliferation of either fibronectin immunoreactive cells or melanocytes. The capacity of Hensen's node to elicit changes in trunk neural crest cell phenotype decreased as the developmental age of the node increased and was lost by stage 6. In addition, old Hensen's node did not stimulate the expression of trunk-specific phenotypes in cranial neural crest cells, suggesting that cranial- and trunk-specific phenotypes are induced by different mechanisms.

Role of the transforming growth factor-beta family in the expression of cranial neural crest-specific phenotypes.

Cranial and trunk neural crest cells produce different derivatives in vitro. Cranial neural crest cultures produce large numbers of cells expressing fibronectin (FN) and procollagen I (PCol I) immunoreactivities, two markers expressed by mesenchymal derivatives in vivo. Trunk neural crest cultures produce relatively few FN or PCol I immunoreactive cells, but they produce greater numbers of melanocytes than do cranial cultures. Treatment of trunk neural crest cultures with transforming growth factor-beta 1 (TGF-beta 1) stimulates them to express both FN and PCol I immunoreactivities at levels comparable to those normally seen in cranial cultures and simultaneously decreases their expression of melanin. These observations raised the possibility that endogenous TGF-beta is involved in specifying differences in the phenotypes expressed by cranial and trunk neural crest cells in vitro. Consistent with this idea, we found that treatment of cranial cultures with a function-blocking TGF-beta antiserum inhibits the development of FN immunoreactive cells and stimulates the development of melanocytes. Cranial and trunk neural crest cells express approximately equal levels of TGF-beta mRNA. However, trunk neural crest cells are significantly less sensitive to the FN-inducing effect of TGF-beta 1 than are cranial neural crest cells. These results suggest that: (1) endogenous TGF-beta is required for the expression of mesenchymal phenotypes by cranial neural crest cells, and (2) differences in the phenotypes expressed by cranial and trunk neural crest cells in vitro result in part from differences in the sensitivities of these two cell populations to TGF-beta.

Treating cigarette smoking in drug-abusing clients.

Clients in substance abuse treatment are at high risk for smoking-related illness due to higher rates and heavier smoking than the general population. Three myths widely held by both treatment staff and substance abusers in treatment-people in treatment do not want to quit smoking, people in treatment will relapse to other drug use if they attempt to quit smoking, and people in treatment are unable to quit smoking-make it difficult to broach the matter of smoking cessation. A 16-week, cognitive-behavioral group program with nicotine patches was conducted at Oregon's largest, private, nonprofit substance abuse treatment agency. Of 490 clients, approximately 85% of whom smoke, 106 (25% of the smokers) were interested enough in quitting to attend an orientation. Approximately 40% of these were methadone maintenance clients. The others were distributed among two residential and two outpatient drug-free treatment services. Of 90 assigned, 68 began voluntary treatment, and 21 were assigned to delayed treatment. Of the 66 smokers who began, 74% succeeded in quitting smoking for at least 1 day, and 23% were abstinent for at least 4 continuous weeks. At the end of the 16-week treatment, 7 subjects (11%) were abstinent. No control subjects quit smoking on their own. The article discusses issues of institutionalizing smoking cessation services in drug treatment agencies.

Screening transvaginal ultrasonography of postmenopausal women in a private office setting.

OBJECTIVE: The objective of this study was to determine the value of screening transvaginal ultrasonography for the evaluation of endometrial or ovarian abnormalities in asymptomatic postmenopausal women in a private gynecology office at the time of yearly examination. STUDY DESIGN: All postmenopausal women who were seen for yearly examination between June 1, 1991, and June 1, 1993, underwent screening transvaginal ultrasonographic examinations that I performed. Women who had any pelvic symptoms or who were premenopausal were excluded from the study group. RESULTS: During the 24 months of this study 478 women were screened. One case of early ovarian carcinoma was diagnosed, one case of superficial adenocarcinoma of the endometrium was discovered, and 28 other ovarian cysts were seen. All women with cystic changes in the ovaries underwent testing for serum CA 125 levels, and follow-up ultrasonography was done at 1 and 3 months. Ovaries were removed if the CA 125 level was elevated, if the cyst became larger, or if the patient desired. No additional ovarian carcinomas were found in those women who had cysts discovered on ultrasonography and who subsequently had the ovaries removed. CONCLUSIONS: Screening transvaginal ultrasonography examinations were well received by all patients, there was no significant associated discomfort, the scans required minimal time, and a significant number of abnormalities were discovered, including two early carcinomas. I believe that when transvaginal ultrasonography is available in an office setting, where it can be performed at no or very low cost, routine screening of postmenopausal women is a valuable addition to the yearly examination.

Purification and characterization of a trophic factor for embryonic peripheral neurons: comparison with fibroblast growth factors.

The validation of NGF as a physiologically important neurotrophic factor has led to intense efforts to identify novel polypeptide growth factors for neurons. We report here the details of a greater than 80,000-fold purification of a neurotrophic molecule, referred to as growth-promoting activity (GPA), from chicken sciatic nerves. The final product of the purification migrated as a protein band of 21.5 kd, its apparent pI was approximately 4.8, and the ED50 of the most active preparation was approximately 10 pg/ml. Amino acid sequence of a proteolytic digestion fragment of GPA revealed homology with the recently published sequences for rabbit and rat sciatic nerve CNTF. Thus this molecule may be the chicken form of CNTF. Analysis of the specificity of action of GPA showed that, in addition to E8 ciliary ganglion neurons, the factor was able to support short-term survival of E8 dorsal root ganglion and E12 sympathetic neurons. This range of specificities of biological action was also seen with both acidic and basic FGF in the presence of heparin. The biological activity of GPA differed from that of FGF in that it was not potentiated by heparin and did not stimulate mitogenesis in chick fibroblasts.