Azole phenoxy hydroxyureas as selective and orally active inhibitors of 5-lipoxygenase

Azole phenoxy hydroxyureas are a new class of 5-lipoxygenase (5-LO) inhibitors. Structure-activity relationship studies have demonstrated that electronegative substituents on the 2-phenyl portion of the oxazole tail increased the ex vivo potency of these inhibitors. Similar substitutions on the thiazole analogs had only minor contribution to the ex vivo activity. The trifluoromethyl-substituted oxazole 24 was the best compound of the oxazole series in both the ex vivo (6 h pretreated rats) and in vivo (3 h pretreated rats) RPAR assay with ED50 values of approximately 1 and 3.6 mg/kg, respectively, but was weakly active in the allergic guinea pig assay. Oxazole 50 was equally active in both the RPAR and guinea pig in vivo models and was similar to zileuton. The unsubstituted thiazole 52 was the best compound of the thiazole series, by inhibiting the leukotriene B4 biosynthesis in the RPAR assay (3 h pretreated rats) by 99%, at an oral dose of 10 mg/kg, and the bronchoconstriction in the allergic guinea pig by 50%, at an intravenous dose of 10 mg/kg. Oxazole 24 demonstrated high and selective 5-LO inhibitory activity in the in vitro assays, with IC50 values ranging from 0.08 microM in mouse macrophages to 0.8 microM in human peripheral monocytes to 1.2 microM in human whole blood. This activity was selective for 5-LO, as concentrations up to 15 microM in mouse macrophages did not affect prostaglandin formation. Oxazole 59 was the most active inhibitor in the human monocyte assay with an IC50 value of 7 nM.

Breast cancer 99mTc SM3 radioimmunoscintigraphy

99mTc SM3 radioimmunoscintigraphy is combined with kinetic analysis and probability mapping using a change detection algorithm to investigate axillary node involvement before primary surgery in patients with breast cancer. Whereas planar imaging was unsuccessful, axillary node involvement was correctly determined in 11 out of 13 patients 6 out of 7 true negatives and 5 out of 6 true positives down to 0.35 grams. A prospective study is underway.

Endocrine effects of GnRH analogue with low-dose hormone replacement therapy in women with endometriosis

OBJECTIVE

GnRH analogues are being used increasingly for a number of oestrogen dependent conditions in women. The resultant profound hypo-oestrogenism is a disadvantage, however, but the preservation of pituitary sensitivity to negative feedback by oestradiol is not well defined. We have determined the effect on gonadotrophins and inhibin of GnRH analogue plus low-dose continuous combined hormone replacement therapy in comparison with GnRH analogue therapy alone.

DESIGN

Randomized controlled trial.

PATIENTS

Fifty premenopausal women with endometriosis randomized to treatment with goserelin alone (Group 1) or goserelin plus 17 beta-oestradiol and medroxyprogesterone acetate (Group 2).

MEASUREMENTS

FSH, LH, oestradiol, oestrone, inhibin before and during treatment.

RESULTS

Oestradiol and oestrone were suppressed in both groups, but Group 2 had significantly higher oestradiol during the hormone replacement therapy period. LH was suppressed in both groups. In Group 1, FSH levels recovered during treatment but, in contrast, in Group 2, FSH levels remained suppressed throughout treatment. Inhibin was significantly lower in Group 2, but not in Group 1, during treatment compared to pretreatment.

CONCLUSIONS

Pituitary secretion of FSH appears to remain responsive to feedback control by oestradiol during GnRH analogue therapy and is incompletely suppressed, unlike LH which remains completely suppressed. The possible mechanisms for this are discussed.

Gonadotropin-releasing hormone analogue (goserelin) plus hormone replacement therapy for the treatment of endometriosis: a randomized controlled trial

OBJECTIVE

To determine whether treatment of endometriosis with a GnRH analogue (GnRH-a; goserelin) combined with continuous estrogen and progestogen hormone replacement therapy (HRT) would prevent the hypoestrogenic effects, including loss of bone density, while maintaining efficacy for treatment of endometriosis.

DESIGN

Randomized controlled trial.

PATIENTS

Fifty premenopausal women with laparoscopically diagnosed endometriosis (revised American Fertility Score for endometriosis implants equal to four or greater) and significant symptoms of dysmenorrhoea, dyspareunia, and other pelvic pain.

INTERVENTION

Patients were randomized to receive either goserelin alone, 3.6 mg SC depot every 4 weeks for 24 weeks, or goserelin, 3.6 mg SC depot every 4 weeks for 24 weeks, plus HRT (25 micrograms transdermal 17 beta E2 daily and 5 mg medroxyprogesterone acetate orally daily) for 20 weeks commencing with the second goserelin injection.

RESULTS

There was a significant reduction in the extent of pelvic endometriosis in both groups, with no difference between the groups. Both groups experienced an improvement in symptoms and signs, again with no difference between groups. Hypoestrogenic side effects of hot flushes and loss of libido were significantly less in the group that received HRT. The amount of bone mineral density loss was significantly less in the HRT group at the lumbar spine, although it was not prevented completely.

CONCLUSION

The addition of HRT to GnRH-a for the treatment of endometriosis did not reduce the efficacy of treatment, and adverse hypoestrogenic effects were decreased, although not abolished.

Effects of the pure anti-oestrogen ICI 182780 on oestrogen receptors, progesterone receptors and Ki67 antigen in human endometrium in vivo

The new steroidal pure anti-oestrogen ICI 182780 was studied for the first time in pre-menopausal women. A total of 30 patients requiring hysterectomy for benign gynaecological disease were randomized to ICI 182780, 12 mg/day i.m. (n = 19) or no treatment (n = 11) for 7 days prior to surgery. Immunohistochemical measurements were made in the snap-frozen, resected endometrium for oestrogen receptors (ER), progesterone receptors (PgR) and Ki67, a nuclear antigen whose expression is closely related to proliferation. Five control patients ovulated prior to surgery and, as expected, the secretory endometria had lower Ki67 antigen concentrations than endometria had lower proliferative phase. The endometria from patients treated with ICI 182780 had reduced Ki67 compared with controls. This demonstration of reduced proliferative activity indicates that the pharmacological effectiveness of the treatment was maintained despite increased plasma oestradiol concentrations. In contrast to results from rodents, ICI 182780 did not markedly reduce ER expression, although there was significantly lower ER in the myometrial cells of the treated group. The lack of effect on PgR shows a dissociation between the drug's effect on this oestrogen-dependent protein and its effects on proliferation.

Diploid and hyperdiploid rat Schwann cell strains displaying negative autoregulation of growth in vitro and myelin sheath-formation in vivo

Neonatal rat Schwann cells were cultured for several months with intermittent exposure to the mitogen, cholera toxin, and infrequent passaging to avoid premature transformation. A cell line SCL4.1/F7 was derived following the cloning of one of these long-term cultures by limiting dilution in liquid medium to select for cells capable of continuous proliferation in the absence of mitogen. F7 cells have been passaged 40 times (80-120 generations) over 14 months. Two substrains were identified at passage 20, one of which ,s diploid and the other which has trisomy 7 (t7). The cell line displays a characteristic flattened or crescent-shaped morphology, substratum adhesion which is calcium-dependent in the millimolar range, and pronounced contact-inhibition of growth. Confluent or subconfluent cultures readily cease proliferation and change to a differentiated (stellate/bipolar) morphology through the mediation of an autocrine growth-inhibitory factor. F7 cells grafted into the site of a crush injury in adult rat sciatic nerves remained viable and myelinated host axons. F7 is the first clonally derived diploid immortal Schwann cell line to have been published and should provide a suitable tool for the study of the biochemical and cellular basis of sheath cell-neuron interactions, myelin stabilization in peripheral nerve and Schwann cell growth autoregulation.

HIV roundtable. Professional perspectives

As the HIV epidemic escalates, concern is mounting over the implications of infection among health care workers. Should all medical professionals be tested? Should supervisors and/or patients be notified if the results are positive? Should the infected PA continue to practice? What about performing surgery? Should he or she be considered impaired? And what about the long-term stress of working with HIV patients? Experts discuss the AAPA's latest recommendations, and share suggestions on prevention and patient care with the audience.

The histologic reliability of laser cone biopsy of the cervix

Laser conization of the cervix has been advocated as the technique of choice for the treatment of cervical intraepithelial neoplasia (CIN) in preference to ablative techniques, because it provides a specimen for histologic diagnosis while retaining the advantages of an outpatient procedure with minimal short- and long-term morbidity. To determine whether specimens so obtained are adequate for reliable histologic diagnosis, we reviewed 77 laser conizations performed for lesions confirmed to contain CIN in a colposcopically directed biopsy and satisfying the criteria for local ablation and scored the cones for the presence of epithelial denudation and laser coagulation artifact that interfered with the diagnosis of CIN or the assessment of the margins of excision. Thirty specimens (39%) were negative for CIN. Twenty-eight (36%) showed extensive epithelial denudation, ten (13%) contained coagulation artifact that made recognition of CIN extremely difficult or impossible, and in 11 (14%), assessment of margins was extremely difficult or impossible because of laser coagulation artifact. We conclude that these difficulties with the histologic interpretation of laser cone specimens make it an unsuitable excisional technique when reliable histologic diagnosis of cervical lesions is required.

Rapid culture confirmation of herpes simplex virus by a monoclonal antibody-based enzyme immunoassay

Rapid confirmation of herpes simplex virus (HSV) is essential in many clinical settings. Viral isolation in cell culture is the standard method for diagnosing HSV infection, with confirmation by specific immunological staining. The performance of the Rapid Absorbent Matrix Pad (RAMP) HSV culture confirmation test was evaluated with specimens obtained from 71 patients with suspected HSV infection and inoculated into African green monkey kidney cell lines. Forty-one culture-positive specimens were confirmed to be HSV by both the RAMP HSV test and the Bartels HSV immunoperoxidase test. Thirty immunoperoxidase-negative specimens were also negative in the RAMP HSV test. The sensitivity and specificity of the RAMP HSV test were 100%. Twelve specimens positive for cytomegalovirus, adenovirus, or enterovirus tested negative by the RAMP HSV test. Thus, the RAMP HSV test was faster than, easier to perform than, as sensitive as, and as specific as other well-documented confirmation methods.

HIV roundtable. Strategies to enhance professional awareness and involvement. Part II

Despite extensive public attention to the social and medical problems associated with HIV infection and AIDS, many clinicians remain largely uninvolved in public health and patient counseling programs aimed at preventing infection and getting patients into treatment. Suggestions to enhance professional involvement include improved schooling and continuing medical education; increased liaison and exchange of information among the various groups working with AIDS patients and at-risk populations; and programs to help clinicians confront their own feelings and concerns relating to AIDS.

HIV roundtable. Strategies to enhance professional awareness and involvement, Part I

Despite extensive public attention to the social and medical problems associated with HIV infection and AIDS, many clinicians remain largely uninvolved in public health and patient counseling programs aimed at preventing infection and getting patients into treatment. Suggestions to enhance professional involvement include improved schooling and continuing medical education; increased liaison and exchange of information among the various groups working with AIDS patients and at-risk populations; and programs to help clinicians confront their own feelings and concerns relating to AIDS.

Cytomegalovirus infection in children with AIDS

Data for 38 children perinatally exposed to human immunodeficiency virus (HIV) were evaluated to determine the impact of cytomegalovirus (CMV) infection on the course of perinatally acquired HIV infection. Thirteen children belonged to the P0 (indeterminate) group, one to the P1 (asymptomatic) group, and 24 to the P2 (symptomatic) group, per the classification of the Centers for Disease Control. Of the 24 children in the P2 group, 10 died. The mean follow-up time was 22.8 months for the 10 children who died and 16.3 months for the 13 children in the P0 group. Serial cultures of urine were performed for all 38 patients. CMV was isolated from seven of 10 children who died and from four of 14 children who survived (P less than .05). Only one of the 13 P0 children was culture-positive for CMV, as compared with 11 of 24 P2 children (P less than .05). All CMV-infected children continued to demonstrate CMV viruria in serial cultures. The mean age at the time of the first culture positive for CMV was 13 months. Microcephaly was present in 15 (65%) of 23 P2 children but in none of the P0 and P1 children (P less than .05). Eight of 11 CMV-infected children were microcephalic; seven of 12 children not infected with CMV were microcephalic (P greater than .05). These data suggest that the prevalence of active CMV infection is significantly higher in P2 children than in P0 and P1 children. In addition, there is a significant association between CMV infection and mortality among P2 children.

Medical imagery in the art of Frida Kahlo

Images

Philippino and Vietnamese women--a study of intrapartum differences

The pregnancies of 140 Philippino women (168 deliveries) and 198 Vietnamese women (250 deliveries) were compared to those of Australian-born women delivered at the Mater Mothers' Hospital, Brisbane over the 5-year period 1980-1984 with the aim of detecting differences in their labour and mode of delivery. The Philippino women were predominantly married to Caucasian men whereas the Vietnamese women were married to Vietnamese men. The study assesses the clinical impression that this difference between the 2 groups affects intrapartum outcome. Birth-weights of the babies of Philippino women followed the same pattern as those of Australian women while Vietnamese women delivered smaller babies. Philippino primiparas had increases in all parameters of labour studied, notably an increased Caesarean section rate, especially those performed in the second stage. Comparable increases were not found in either Philippino multiparas or Vietnamese women. Based on these results 'relative' cephalopelvic disproportion is postulated among the Philippino women.

Levels of the small insulin-like growth factor-binding protein are strongly related to those of insulin in prepubertal and pubertal children but only weakly so after puberty

We have looked at the relationship between fasting levels of insulin and a small insulin-like growth factor (IGF)-binding protein (IBP-1) in a cross-sectional study of 116 normal subjects aged 5-48 years. The relationship between IBP-1 and insulin was also examined within individual normal children in overnight profiles of IBP-1 and insulin obtained from two children at each stage of puberty (Tanner stages 1-5). In the cross-sectional study high levels of IBP-1 were found in early childhood and these fell throughout puberty as fasting levels of insulin rose. Multiple regression analysis revealed that both these changes were predominantly due to pubertal development rather than to age. After the age of 16 IBP-1 levels remained low despite fasting insulin levels returning to prepubertal levels. A strong negative correlation was obtained between IBP-1 and insulin in children of 5-16 years (r = -0.63; n = 60; P less than 0.001), no such relationship being found after the age of 16. In the second study, IBP-1 underwent a marked circadian variation in all cases and an inverse correlation with insulin, measured at the same time, was obtained at pubertal stages 1 to 4, but not at stage 5 (pooled data stages 1-4, r = -0.69; n = 53; P less than 0.001). We have demonstrated that a potential inhibitor of IGF-activity is inversely related to insulin throughout the period of active GH-related growth and that this relationship weakens after puberty.

Circulating levels of placental protein 12 in complications of first trimester pregnancy

Serum placental protein 12 (PP12) levels were determined in 34 women with threatened miscarriage in whom a diagnosis of anembryonic pregnancy (n = 19), missed abortion (n = 4), complete or incomplete abortion (n = 5), hydatidiform mole (n = 1) and subsequent abortion of a live fetus (n = 5), was made ultrasonically and confirmed by histological examination. Twenty-four of the 34 patients had one or more levels between the 10th and 90th centiles of the reference range. In 7 of the 19 patients (37%) with anembryonic pregnancy and in 3 of the 4 patients (75%) with a missed abortion, PP12 levels were markedly elevated. However, in cases where serial measurements were available (n = 6), PP12 levels were seen to fall in all cases. It is concluded that pregnancies that have failed or will subsequently fail in the first or second trimester are not associated with depressed maternal PP12 levels, suggesting that the decidual synthesis of this protein is independent of the presence or viability of the fetus.