Parathyroid hormone-related protein mRNA in sheep endometrium and myometrium during late gestation and labor

OBJECTIVE

To determine quantitative changes of parathyroid hormone-related protein (PTHrP) mRNA in sheep myometrium and endometrium during late gestation and labor.

METHODS

Tissues were obtained from 22 pregnant ewes under halothane anesthesia: early controls at 131 days' gestational age (dGA) not in labor (ECNL; n = 6); during cortisol-induced premature labor (CPL at 131 dGA; n = 6); in term spontaneous labor (STL at 140-145 dGA; n = 5); or term control animals not in labor (TCNL at 140-145 dGA; n = 5). Total RNA was extracted and subjected to Northern blot analysis. Blots were probed with a human PTHrP cDNA probe, stripped, and rehybridized with an 18s rRNA nucleotide probe to normalize PTHrP mRNA levels.

RESULTS

Endometrial PTHrP mRNA:18s was unaffected by gestational age or labor in tissues from the four groups. In contrast, myometrial PTHrP mRNA:18s ratio was decreased when TCNL and STL were compared with both ECNL and CPL groups (P < .05).

CONCLUSIONS

Significant changes occur at the end of gestation in pregnant ovine myometrium PTHrP mRNA but not in the endometrium. In myometrium PTHrP mRNA levels were down-regulated at term regardless of whether labor was present. It seems that PTHrP mRNA levels in myometrium are related to gestational age rather than to labor per se in sheep. We hypothesize that PTHrP may play a role in maintaining uterine quiescence until term, at which time levels fall allowing myometrial contractile activity to increase unopposed by PTHrP.

Body fat distribution and race differences in apolipoprotein A1

OBJECTIVE

This is the first study to assess the role of waist-to-hip ratio in explaining race differences in levels of serum apolipoprotein A1, a protective risk factor for atherosclerosis.

METHODS

Linear regression analyses were used in a community-based survey of 3,043 adults (23.5% African-American) to assess associations of race, age, anthropometric measures, education, diabetes, blood pressure medication use, cigarette smoking, and leisure-time physical activity with apolipoprotein A1 levels.

RESULTS

Higher apolipoprotein A1 levels were observed among African-American than among white adults (African-American men: +15.6 mg/dl than white men, African-American women: +3.1 mg/dl more than white women; p < 0.05). Waist-to-hip ratio and other variables did not account for race differences among men. African-American women had +8.6 mg/dl higher levels than white women after adjustment for differing distributions of waist-to-hip ratio, age, body mass index and education. Cigarette smoking, physical activity, and medical history accounted for no further differences among women.

CONCLUSIONS

Higher levels of obesity indicators and lower educational attainment among African-American women reduced a potentially greater beneficial race difference in apolipoprotein A1. These findings also suggest that other environmental and biochemical factors may play roles in explaining the higher protective levels of apolipoprotein A1 observed among African-American children and adults.

The Q-switched neodymium:YAG laser and tattoos: a microscopic analysis of laser-tattoo interactions

The Nd:YAG laser effectively removes or lightens amateur and professional tattoos. The biomechanics of the removal of tattoo particles at the cellular level are incompletely understood. We examined biopsies obtained from 35 amateur and professional tattoos (including coloured tattoos), treated on three or more occasions with the Nd:YAG laser. Biopsies taken immediately after laser treatment showed vacuolation with complete clearance of tattoo particles in the most superficial layers of the dermis, as assessed by light and electron microscopy. We propose that the 'disappearance' of the tattoo particle arises from the formation of atomic species and gaseous products, which are rapidly dissolved in the extracellular fluid. Residual fragmented particles that are commonly found in the mid- and lower dermis are rephagocytosed. The interaction between the Nd:YAG laser and black tattoo particles at 1064 nm, and red tattoo particles at 532 nm, appears to be specific, as there was little evidence of thermal damage to adjacent cells or stromal collagen.

Developmental outcomes of children with myelomeningocele: prenatal predictors

OBJECTIVE

The purpose of the current investigation was to determine cognitive developmental outcomes for a cohort of children with prenatally detected myelomeningocele and to determine whether the variables of (1) severity of ventriculomegaly and (2) anatomic level of lesion were predictive of cognitive development.

STUDY DESIGN

Prenatal ultrasonographic examinations were reviewed by a single perinatologist to determine the degree of ventriculomegaly and the anatomic level of the lesion. Ventriculomegaly was defined as a lateral ventricular atrial width > 10 mm. Anatomic level of lesion was defined as (1) thoracic, (2) high lumbar, (3) midlumbar, (4) low lumbar-high sacral, or (5) sacral. Cognitive developmental quotients for surviving children were determined by one of two developmental pediatricians with use of a modified version of the Clinical Adaptive Test/Clinical Linguistic Auditory Milestone Scale, a measure of visual-motor and language abilities.

RESULTS

The mean cognitive developmental quotient for subjects with absent to mild ventriculomegaly was 90.3 (range 54 to 120, SD 17.4), whereas the mean cognitive developmental quotient for those with moderate to severe ventriculomegaly was 74.0 (range 65 to 100, SD 17.1) (p < 0.01). There was a negative correlation between the degree of ventriculomegaly and the cognitive developmental quotient (r = -0.43, p < 0.025) and a positive correlation between the level of the lesion and the cognitive developmental quotient (r = 0.50, p < 0.01).

CONCLUSIONS

The degree of ventriculomegaly determined on high-resolution prenatal ultrasonography is predictive of early cognitive development in children with myelomeningocele, with worsening ventriculomegaly being associated with lower cognitive developmental quotients. The anatomic level of the lesion also has predictive value, with lower level lesions being associated with more favorable cognitive outcomes. However, because of the high degree of variance in developmental quotients within the two ventriculomegaly groups, we advise clinicians to use caution in the interpretation and use of our data.

Adult height in patients with childhood onset atopic dermatitis

Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.

Reversible dilated cardiomyopathy following treatment of atopic eczema with Chinese herbal medicine

Chinese herbal medicines are increasingly being used as an alternative treatment for chronic skin disease. Most patients and many doctors remain insufficiently aware of their potential toxicity. We report a patient with eczema who developed a severe cardiomyopathy following a 2-week course of Chinese herbal medicine. The connection between the two conditions was not made until 2 weeks after presentation when the patient was specifically asked if she had ingested any unusual substances. The belief that herbs, as natural products available without prescription, are harmless, is commonplace and patients may not consider them worthy of mention during a standard medical history.

Self-reported prevalence of diabetes and preventive health care practices among people with diabetes in South Carolina

In conclusion, South Carolina has a higher prevalence of diabetes compared to the national average. Age is a major factor associated with increased prevalence. African Americans had a disproportionately higher prevalence of diabetes relative to white Americans in South Carolina. Compared to the standards of diabetes care recommended by the ADA, health care practice by people with diabetes and health professionals still needs to be improved. Diabetes communication programs, including diabetes education for people with diabetes and health professional education, continue to be necessary for the improvement of diabetes care.

Giant glioependymal cyst resembling holoprosencephaly on prenatal ultrasound: case report and review of the literature

We report the earliest in utero presentation of a 'giant' glioependymal cyst detected on routine prenatal ultrasound at 22 weeks estimated gestational age. The clinicopathologic features of these rare lesions are reviewed as well as previous reports of glioependymal cysts detected in utero. The effects of large intracranial cysts on neurodevelopment are discussed as well as the differential diagnosis of infantile intracranial cysts and therapeutic alternatives.

Evaluation of the Nd/YAG laser for treatment of amateur and professional tattoos

Two hundred and twenty-one amateur tattoos and 27 professional tattoos were treated with a Nd/YAG laser (lambda 1064 nm and 532 nm). The response was expressed as the percentage area cleared of tattoo. Seventy-nine per cent of amateur black tattoos were > or = 75% clear after one to five treatments (mean 2) at 1064 nm. The response of professional tattoos was slower and less complete. Seventy-four per cent of black professional tattoos were > or = 75% clear after one to 11 treatments (mean 6.3) at 1064 nm. Red tattoos responded well to 532 nm and were > or = 75% clear after one to five treatments. Yellow, orange, blue and green tattoos were resistant to treatment. Side-effects included minor scarring in 1.2% of tattoos and transient pigmentary changes in 77% of patients.

Functional motor outcome in children with myelomeningocele: correlation with anatomic level on prenatal ultrasound

Fifteen children with prenatally diagnosed myelomeningocele were followed for at least three years to determine the relations between prenatal anatomic level visualized on high-resolution ultrasound, radiographic level, neuromotor level and functional motor outcome. Prenatal anatomic level accurately predicted neuromotor level and functional motor outcome in 12 of the children and was a better predictor than motor level at birth. Clinicians involved in prenatal counseling may use the anatomic level determined on high-resolution ultrasound to discuss motor prognosis with families.

Fetal radiation exposure is minimal after pelvimetry by modified digital radiography

OBJECTIVE

Our purpose was to determine the maximal fetal exposure to radiation by use of thermoluminescent dosimeters when pelvic measurements were performed by standard or modified digital radiography.

STUDY DESIGN

Digital radiography of the pelvis was performed according to a standard technique. Lithium fluoride thermoluminescent dosimeters were positioned on the patient's skin to quantitate the maximal amount of radiation exposure to the fetus. The standard technique often included a portion of fetal vertex. The axial view technique was modified to use an angle of inclination of 17 to 29 degrees relative to the vertical axis.

RESULTS

Digital radiography was well tolerated and interpretable images were consistently obtained. The maximal dose to the fetal vertex by use of the standard digital axial slice was 465 mrad. By modifying the standard digital technique and using an angle of inclination of 17 to 29 degrees it was possible to obtain an axial section without including any portion of the fetal vertex. This reduced the maximal total dose to the fetal vertex to 55 mrad, which is less than the background radiation exposure to the fetus over a 9-month period from natural sources.

CONCLUSION

Data reported indicate that total fetal radiation exposure is minimal after pelvimetry by digital radiography. Incorporating the modification of the angle for the axial slice, as reported here, resulted in a further significant decrease in fetal radiation exposure.

Vertical and horizontal transmission of unique Candida species to premature newborns

The number of nosocomial bloodstream infections due to Candida species in critically ill newborns is increasing. This pathogen may be vertically transmitted from the mother or nosocomially acquired in the nursery. The goal of this study was to identify the route of transmission of unique Candida species and strains from mothers to their preterm offspring. Specimens from mothers for fungal cultures were obtained before delivery, and specimens from infants for sequential fungal cultures were obtained at defined intervals. Candida species were identified by standard methods and were typed by electrophoretic karyotyping (EK) and restriction endonuclease analysis of genomic DNA (REAG) with pulsed-field gel electrophoresis. Antifungal susceptibility testing was performed on all isolates. Fungal cultures were positive for Candida species in 12 (63%) of 19 mothers' specimens and in seven (33%) of 21 infants' specimens. EK and REAG revealed that both the mother and the infant in three (14%) of 21 mother-infant pairs were colonized with the identical strain of Candida albicans. C. albicans was most commonly transmitted vertically. Candida parapsilosis colonized other infants and could not be accounted for by a maternal reservoir.

Enalapril-induced toxic pustuloderma

Enalapril is widely prescribed for hypertension and cardiac failure. Rashes are an uncommon side-effect, occurring in approximately 1.4% of patients, and in approximately 0.4% of patients the rash is sufficient to require discontinuation of enalapril. (Merck Sharp and Dohme, pers. comm.) We report a case of toxic pustuloderma related to enalapril therapy for congestive cardiac failure. To our knowledge enalapril-induced toxic pustuloderma has not been previously reported.

Concentration and separation of hypoglycemic drugs using solid-phase extraction-capillary electrophoresis

Solid-phase extraction-capillary electrophoresis (SPE-CE) is a technique whereby very dilute analytes may be selectively extracted from a sample matrix and concentrated on-line for analysis. This study describes the first phase in the development of a method exploiting this technique for the direct analysis of hypoglycemic drugs in urine. Effective separation and detection of six sulfonylurea drug standards at concentrations below the detection limit of conventional capillary electrophoretic techniques is shown to be attainable. Since surfactant interfered with the on-line concentration process, non-MEKC (micellar electrokinetic chromatography) separation conditions were defined. Using 250 mM borate/5 mM phosphate at pH 8.4, all drugs in a mixture at 285 ng/ml were effectively extracted, concentrated from an injected volume of 2.5 microliters, non-selectively desorbed with an organic-based elution buffer and electrophoretically resolved. Sample loading was found to be linear in the 0.12-1.9 microliters range and drugs in a volume of up to 190 microliters could be concentrated and detected with a sensitivity of approximately 5 ng/ml. Not only was resolution of the desorbed material uncompromised by the presence of the SPE-tip, but separation of glipizide and glyburide was observed despite the fact that these drugs were unresolved under the same separation conditions by standard capillary zone electrophoresis (CZE). From these results, it is clear that SPE-CE not only increases the sensitivity for detection but that selectivity may be altered due to chromatographic processes occurring on the solid-phase resin.

Detection of hypoglycemic drugs in human urine using micellar electrokinetic chromatography

Micellar electrokinetic chromatography (MEKC) is evaluated as a potential analytical method for the separation and detection of a series of sulfonylurea drugs used in the treatment of hyperglycemia. These drugs are often surreptitiously abused, producing extremely low blood glucose levels and symptoms indistinguishable from those associated with an insulin-secreting tumor. Separation buffer containing 50 mM sodium dodecyl sulfate (SDS) was found to be adequate for the MEKC separation of the third generation drugs (glipizide and glyburide) but not the second generation drugs (acetohexamide chlorpropamide, tolazamide, and tolbutamide). At a pH of 8.5 in the presence of 20 mM borate/20 mM phosphate and 150 mM SDS, all seven components were adequately resolved with an analysis time of 17 min. Altering the concentration of the buffering components to either 5 mM borate/5 mM phosphate or 40 mM borate alone reduced the analysis time to less than 10 min with no observable loss in resolution. A series of other micelle-forming surfactants were evaluated, and only sodium cholate provided an improvement over the SDS-based system. Optimal separation was obtained with 75 mM sodium cholate and led to complete analysis with baseline resolution of all seven components in less than 8 min. These conditions were shown to be adequate for the detection of the hypoglycemic drugs spiked into normal urine and in patients taking these drugs. The precision associated with nine consecutive injections of six samples (n = 54) was found to be acceptable with percent coefficient of variance for absolute migration times (MTabs) for all peaks averaging 0.89 with peak area and peak height being 8.49 and 8.26, respectively. The between-sample precision was found to average 0.92% for MTabs and 8.56% and 8.45%, respectively, for the relative peak area and peak height. With a detection limit for the drugs in urine (following extraction) in the 50 ng/mL range, the potential exists for an MEKC-based assay for the detection of sulfonylurea drugs in urine.

Predictors of adopting leisure-time physical activity among a biracial community cohort

Literature on the correlates and predictors of leisure-time physical activity among African-American population is sparse. This cohort study assessed correlates of leisure-time physical activity (specific large muscle activities during the past month at least three times a week) in a biracial population in 1987 and predictors for the adoption of this behavior 4 years later among those initially inactive. Random digit dialing methods were used to identify residents of two South Carolina communities in 1987. In 1991, 3,223 of these residents were resurveyed (62% response rate). In general, the correlates of leisure-time physical activity (education, > or = 12 years; nonsmoking; weight loss behaviors; and physician advice) were similar for each sex and race group. In 1987, the definition of leisure-time physical activity was not met by 831 (54% of 1,542) white women, 374 (76% of 489) African-American women, 586 (59% of 991) white men, and 126 (63% of 201) African-American men. Among those who were inactive in 1987, 22-24% of white adults and African-American men and 14% of African-American women adopted physical activity 4 years later. Twelve years or more of education was a predictor among white women (risk ratio = 1.7, 95% confidence interval 1.2-2.6) and African-American women (risk ratio = 3.1, 95% confidence interval 1.4-6.9), but not among men. Having a physician discuss physical activity was a predictor among white women (risk ratio = 1.9, 95% confidence interval 1.3-2.7), African-American women (risk ratio = 1.7, 95% confidence interval 0.9-3.2), white men (risk ratio = 2.0, 95% confidence interval 1.3-3.1), and African-American men (risk ratio = 2.7, 95% confidence interval 1.0-7.6). These results highlight the strong effect of educational attainment on adoption of healthy behaviors and support the involvement of physicians to promote physical activity among all race and sex groups.

Expression of parathyroid hormone-related peptide and its receptor messenger ribonucleic acid in human amnion and chorion-decidua: implications for secretion and function

OBJECTIVE

Our purpose was to define the location and packaging of parathyroid hormone-related peptide in amnion-chorion and the potential target tissues for its action in fetal membranes.

STUDY DESIGN

We studied fetal membranes by use of light microscopic immunocytochemistry with three monoclonal antibodies against distinct regions of the parathyroid hormone-related peptide molecule. For electron microscopy immunogold analysis with a monoclonal antibody specific to the 109-141 fragment was used to observe parathyroid hormone-related peptide intracellularly in amnion membrane and in the chorion layers. Multiplex reverse transcriptase-polymerase chain reaction with Southern blotting was used to identify parathyroid hormone/parathyroid hormone-related peptide receptor and control messenger ribonucleic acids in amnion and chorion-decidua.

RESULTS

All monoclonal antibodies revealed immunoreactive parathyroid hormone-related peptide in the amniotic epithelial cells and in some fibroblast-like cells embedded in the extracellular matrix of the amnion. Parathyroid hormone-related peptide was also found in the chorion in fibroblast and trophoblast layers and in decidua. Ultrastructurally immunogold particles were evenly distributed throughout the amniotic epithelial cells and were present in apical microvilli and near the basal membranes. Electron microscopy studies of the chorion cytotrophoblast also showed freely dispersed immunogold particles of parathyroid hormone-related peptide with no packaging in secretory granules. Low to undetectable levels of parathyroid hormone/parathyroid hormone-related peptide receptor messenger ribonucleic acid were found in amnion tissue, whereas abundant receptor messenger ribonucleic acid was found in chorion-decidua.

CONCLUSIONS

These results suggest the presence of a parathyroid hormone-related peptide paracrine system within the human fetal membranes.

Interleukin-1 beta and interleukin-4 increase parathyroid hormone-related protein secretion by human umbilical vein endothelial cells in culture

OBJECTIVE

Our purpose was to learn whether cytokines such as interleukin-1 beta and related (or antagonistic) cytokines, hormones, and growth factors could regulate secretion of the vasorelaxant parathyroid hormone-related protein in human umbilical vein endothelial cells in culture.

STUDY DESIGN

Secondary cultures of human umbilical vein endothelial cells were grown to confluence and treated with interleukin-1 beta, an array of factors with possible regulatory actions (cytokines, growth factors, vasoactive peptides, and steroids), and a phorbol ester as a stimulatory control. After 24 hours immunoreactive parathyroid hormone-related peptide in the media was measured by a two-site sandwich radioimmunoassay. The mechanism of interleukin-1 beta action was probed with interleukin-1 beta receptor antagonist and selected inhibitors.

RESULTS

Interleukin-1 beta (10 ng/ml) produced up to an eightfold increase in parathyroid hormone-related peptide secretion from human umbilical vein endothelial cells in culture (p < 0.01). Half-maximal stimulation was seen at 0.23 ng/ml. Interleukin-1 receptor antagonist, cycloheximide, and actinomycin D blocked the effects of interleukin-1 beta (p < 0.05). Interleukin-4 at 10 ng/ml and phorbol 12-myristate 13-acetate at 10(-7) mol/L significantly increased the secretion of parathyroid hormone-related peptide by human umbilical vein endothelial cells (p < 0.05). The time course of each interleukin showed an effect beyond 12 hours. The effects of interleukin-1 beta and interleukin-4 appeared to be specific, because a large series of related interleukins and other growth factors and cytokines were without effect.

CONCLUSION

Interleukin-1 beta and interleukin-4 increase parathyroid hormone-related protein secretion in human umbilical vein endothelial cells in culture. Because interleukin-1 beta messenger ribonucleic acid has been found in umbilical cord endothelial cells, we propose that the umbilical cord has a novel vasorelaxant regulatory system that uses interleukin-1 beta endothelial action and secretion of the vasorelaxant parathyroid hormone-related peptide.

Elevated maternal serum alpha-fetoprotein levels: what is the risk of fetal aneuploidy?

OBJECTIVE

Our purpose was to present the findings of a project to determine the efficacy of including routine fetal karyotyping in the investigation of an elevated maternal serum alpha-fetoprotein concentration.

STUDY DESIGN

Targeted ultrasonographic examinations were performed in 658 patients with elevated maternal serum alpha-fetoprotein levels. The scans were normal in 557 women, of whom 427 consented to amniocentesis; 435 fetuses were karyotyped. In the 101 patients with abnormal ultrasonographic examinations 75 had fetal karyotyping.

RESULTS

In the 435 fetuses with normal scans, two had karyotypic anomalies, a 47,XYY and an inherited balanced translocation. Three fetuses with normal karyotypes and high amniotic fluid alpha-fetoprotein levels had congenital nephrosis. In the 101 patients with abnormal scans, 75 fetuses were karyotyped. There were four aneuploidies. Among the 26 patients with abnormal scans who declined amniocentesis one fetus with multiple anomalies was karyotyped after delivery and triploidy was discovered.

CONCLUSIONS

These results provide little justification for including fetal karyotyping in the investigation of elevated maternal serum alpha-fetoprotein when the targeted ultrasonographic examination is normal. When it is abnormal, selective rather than routine karyotyping is more appropriate.

Separation of urinary estrogens by micellar electrokinetic chromatography

Urinary estrogen levels are important for monitoring the normal pregnancy process as well as for the diagnosis of reproductive diseases. 17 beta-Estradiol and estrone are maintained at very low concentrations in urine and, therefore, are difficult to determine using standard chromatography with UV detection. In the present study, we describe a potential method for the determination of urinary estrogens (estrone, estradiol and estriol) using a solid-phase extraction and rapid capillary electrophoretic (CE) separations. Micellar electrokinetic chromatographic (MEKC) analysis was optimized by evaluating the number of surfactants in a 5 mM borate-5 mM phosphate separation buffer, of which sodium cholate (75-90 mM) was found to be optimal. Changing the hydrophobic character of the separation buffer with organic additives had a significant effect on the resolution of the three estrogens and an internal standard (d-equilenin). The addition of an organic additive (20% acetonitrile) was found to be necessary for the resolution of all components of the mixture. Substitution with 20% methanol provided a similar separation with better resolution but at the cost of increased analysis time. Analysis of two extracted urine samples from 18-weeks and 21-weeks pregnant women showed that, with the present technology, CE can provide adequate resolution and superior speed, but the sensitivity limits attainable with the existing technology may limit its utility to the measurement of estriol and estrone.

Continuous infusion of 5-fluorouracil with alpha 2b interferon for advanced colorectal carcinoma

Thirty patients with symptomatic colorectal carcinoma were commenced on treatment with 5-fluorouracil (2.5 g week-1) administered by continuous intravenous infusion and alpha 2b interferon (3 x 10(6) U s.c. three times a week). Six out of 30 patients (20%) achieved a partial response. Three patients (10%) had stable disease and 21 patients (70%) progressed on treatment. Twenty patients (67%) completed ten or more weeks of treatment. In nine patients, treatment was withdrawn after 2-9 weeks because of disease progression or death. One patient's treatment was interrupted by emergency surgery. The median survival for all patients was 210 days (7 months). The principal side-effects were oral mucositis (12/30 patients), nausea (8/30 patients) and transient diarrhoea (4/30 patients), and initial constitutional symptoms due to alpha 2b interferon. The combination of low-dose continuous infusional 5-fluorouracil and low-dose alpha 2b interferon is well tolerated but has no obvious advantage over alternative infusional regimens using 5-fluorouracil as a single agent.

Early prenatal diagnosis of an infratentorial arachnoid cyst: association with an unbalanced translocation

Arachnoid cysts are an uncommon central nervous system malformation, representing only 1 per cent of all intracranial masses. We report the second-trimester prenatal diagnosis of a posterior fossa arachnoid cyst, associated with an unbalanced X;9 translocation.

Phenotypic heterogeneity in breast fibroblasts: functional anomaly in fibroblasts from histologically normal tissue adjacent to carcinoma

Histologically normal breast tissue was obtained from women undergoing surgery for benign breast lesions (n = 12) and mammary carcinomas (n = 15). Four fibroblast subpopulations (FI, FII, FIII and FIV) were isolated from these specimens by differential digestion and centrifugation. FI cells were the first to be released from the tissue digest and consequently assumed to be derived from the interlobular stroma; FIV fibroblasts were tightly associated with the epithelial organoids and are therefore believed to be of intralobular origin. These cells were characterised in terms of their migratory phenotype (classified as either foetal- or adult-like) and the production of motility factors according to previously described techniques. FI fibroblasts obtained from patients with benign breast lesions displayed a foetal migratory phenotype (10/11) and secreted detectable quantities of motility factors (11/11). In contrast, none of the FIV fibroblasts (0/10) obtained from these same patients displayed a foetal-like migratory phenotype or secreted motility factors. In the case of fibroblasts obtained from cancer patients, both FI (13/13) and FIV (13/13) fibroblasts displayed a foetal-like migratory phenotype and secreted motility factors. Fibroblasts were also derived from skin (n = 12) and breast fat tissue (n = 4) of certain patients. In agreement with our previously published observations, skin fibroblasts obtained from non-cancer and cancer patients also differed in terms of their migratory behaviour: none of the skin fibroblast lines (0/5) obtained from non-cancer patients were foetal-like, compared to 3/7 lines from cancer patients. All fat-derived fibroblasts (1 non-cancer and 3 cancer patients) were also foetal-like. Our results indicate (i) functional heterogeneity between FI and FIV fibroblasts of normal breast, and (ii) the presence of functionally aberrant (i.e., foetal-like) FIV fibroblasts in histologically normal breast tissue adjacent to a carcinoma.

Attenuation of agonist-induced desensitization of the rat substance P receptor by microinjection of inositol pentakis-and hexakisphosphates in Xenopus laevis oocytes

Recently, inositol hexakisphosphate (phytic acid) was shown to bind to photoreceptor arrestin and block its interaction with rhodopsin. Such an interaction might predict that inositol polyphosphates could alter G protein-coupled receptor desensitization. To investigate the possible roles of higher inositol polyphosphates on receptor desensitization, we have expressed the rat substance P receptor in Xenopus laevis oocytes. The functional expression of substance P receptor was monitored by voltage-clamp recording of substance P-induced Ca(2+)-dependent Cl- currents. When control oocytes were stimulated with substance P (30 nM), after 10 min of washing the second responses to substance P were approximately 15% of the first responses. Cytosolic injection of inositol pentakisphosphate (100 microM) or inositol hexakisphosphate (100 microM) inhibited the reduction of the second substance P-induced current responses, maintaining the second responses to 57-58% of the initial responses. The protective effects of inositol pentakisphosphate and inositol hexakisphosphate against agonist-induced desensitization were concentration and time dependent and structurally specific, in that inositol hexasulfate and inositol tris- and tetrakisphosphate isomers were inactive. Microinjection of inositol hexakisphosphate did not (a) change the potency of substance P or the sensitivity of the expressed substance P receptor to substance P, (b) inhibit 12-O-tetradecanoylphorbol-13-acetate-induced loss of substance P-induced current responses, or (c) alter the currents elicited by microinjection of inositol-1,4,5-trisphosphate. These results suggest that inositol pentakisphosphate and inositol hexakisphosphate have specific inhibitory effects on the agonist-induced loss of responsiveness of the rat substance P receptor. Moreover, these protective effects of inositol hexakisphosphate against desensitization were also observed with the endogenous lysophosphatidic acid/phosphatidic acid receptor, indicating that this mechanism is not specific to ectopic receptors. These results suggest that inositol pentakisphosphate and inositol hexakisphosphate may be novel pharmacological tools for the study of agonist-induced desensitization.