New Species of Lissodendoryx Topsent, 1892 (Demospongiae, Poecilosclerida, Coelosphaeridae) and Myxilla Schmidt, 1862 (Demospongiae, Poecilosclerida, Myxillidae) from the Northeast Pacific.

Collections of sponges by the late Dr. William C. Austin and the authors (N. McDaniel, R. Harbo and B. Ott) provided material for descriptions of new species from two genera of Poecilosclerida for shallow waters of Southern British Columbia, Canada and Northern Washington, USA: Lissodendoryx and Myxilla. There have been no new species of these two genera described for the Northeast Pacific since Laubenfels' work in central California (Laubenfels 1930, 1932) and Lambe's reports in 1893 to 1895 for Geological Survey of Canada sponge collections from British Columbia, Canada to the Bering Sea. We describe three new species of Lissodendoryx (Lissodendoryx) (Demospongiae, Poecilosclerida, Coelosphaeridae) and one new species of Myxilla (Myxilla) (Demospongiae, Poecilosclerida, Myxillidae): L. (L.) barkleyensis n. sp., L. (L.) littoralis n. sp., L. (L.) toxaraphida n. sp. and M. (M.) austini n. sp. Lissodendoryx (L.) barkleyensis n. sp. is cave-dwelling, has acanthostyles 112-260 µm, tornotes 107-177 µm, arcuate isochelas 8-28 µm and two sizes of sigmas 18-29, 26-55 µm. Lissodendoryx (L.) littoralis n. sp. fistulate habitus is adapted to muddy substrates similar to some Polymastia species also found commonly in the Northeast Pacific. It has subtylostyles 185-336 µm, tylotes 112-229 µm, arcuate isochelas 11-23 µm, and sigmas 30-75 µm. Lissodendoryx (L.) toxaraphida n. sp. is the only described Lissodendoryx species with raphides shaped like toxas. It has acanthostyles 140-286 µm, tornotes 143-195µm, arcuate isochelas 18-34 µm and toxiform raphides 65-156 µm. Myxilla (M.) austini n. sp. has a fistulate habitus and both tornote and tylote megascleres. It appears to be tolerant of low oxygen environments. Myxilla (M.) austini n. sp. has smooth to sparsely spined styles 193-353 µm, tylotes 153-221 µm, tornotes 174-260 µm, two sizes of anchorate isochelas 13-27, 42-81 µm, and two sizes of sigmas 13-47, 33-78 µm. All specimens were collected from shallow water (intertidal to 25 m).

Salmonid microarrays identify intestinal genes that reliably monitor P deficiency in rainbow trout aquaculture.

Nutrient-responsive genes can identify important metabolic pathways and evaluate optimal dietary levels. Using a 16K Salmo salar microarray, we identified in rainbow trout (Oncorhynchus mykiss) 21 potential phosphorus (P)-responsive genes, mainly involved in immune response, proteolysis or transport, whose expression levels changed in the intestine after 5 days of feeding a low-P (LP) diet. Diet-induced changes in the expression levels of several genes in each fish were tightly correlated with changes in serum P, and the changes persisted for an additional 15 days after dietary P deficiency. We then evaluated these and previously identified P-responsive genes under simulated farm conditions, and monitored the intestinal gene expression from 6 h to 7 days after the trout were switched from a sufficient-P (SP) diet to a LP diet (SP-->LP), and from a LP diet to a SP diet (LP-->SP). After 7 days, mean serum P decreased 0.14 mM/day for SP-->LP and increased 0.10 mm/day for LP-->SP. The mRNA abundance of the metalloendopeptidase meprin 1alpha (MEP1alpha), the Na(+)-dependent phosphate co-transporter (NaPi2b,SLC34A2), the sulfotransferase SULT2beta1 and carbonic anhydrase XIII genes all increased after SP-->LP and decreased after LP-->SP, suggesting that adaptive expression is reversible and correlated with dietary P. The duration of change in gene expression in response to SP-->LP was generally shorter than that of LP-->SP, suggesting potentially different mechanisms of adaptation to deficiency as opposed to excess. Diet-induced changes in mRNA abundance of other genes were either transient or modest. We identified, by heterologous microarray hybridization, new genes sensitive to perturbations in dietary P, and then showed that these genes can reliably monitor P deficiency under field conditions. Simultaneous changes in the expression of these P biomarkers could predict either P deficiency (to prevent economic losses to the farmers) or P excess (to prevent inadvertent pollution of nearby waters).

Oblique reformation in cervical spine computed tomography: a new look at an old friend.

STUDY DESIGN: Cervical spine computed tomograms were evaluated for neural foraminal stenosis in both the standard axial plane and the oblique reformatted plane. OBJECTIVE: To assess whether oblique reformation of cervical spine computed tomograms reduces interobserver variability in the evaluation of neural foraminal stenosis. SUMMARY OF BACKGROUND DATA: Radiographic assessment of neural foraminal stenosis is subjective, may vary among observers, and can affect surgical planning. METHODS: The cervical spine images from 19 patients with various degrees of neural foraminal stenosis were reformatted in an oblique plane perpendicular to the long axis of the right and left neural foramens. Seven independent observers graded the degree of foraminal stenosis (none, mild [1-25%], moderate [26-75%], or severe [>75%]) and their confidence level (definite, probable, possible) on both the axial images and the oblique reformations. RESULTS: The ages of the 12 male (mean, 67.5 +/- 13.24 years) and 7 female (mean, 62.7 +/- 14.79 years) patients ranged from 39 to 83 years. Interobserver variability was assessed with chi2 analysis. Rates of agreement on degree of stenosis (chi2 = 19.94; df= 9; P< 0.02) were significantly higher for oblique reformations. Confidence ratings also were significantly higher for oblique reformations (chi2 = 18.19; df= 7; P< 0.02). CONCLUSIONS: Oblique reformation of cervical spine images significantly reduces the degree of interobserver variability and increases observer confidence in the assessment of neural foraminal stenosis. Oblique reformations should be considered in the routine evaluation of neural foraminal stenosis.

Racial differences in vaginal douching knowledge, attitude, and practices among sexually active adolescents.

STUDY OBJECTIVE: The study sought to assess knowledge of, attitude toward, and practices of vaginal douching among adolescent females attending a public family planning clinic, in order to better understand racial influences on douching. DESIGN, SETTING, PARTICIPANTS: In this descriptive, cross-sectional study, a one-page questionnaire was administered to all adolescent females (< or=19 years) presenting to a public family planning clinic in a small southern city between March 1 and May 31, 1999. RESULTS: Of the 169 participants, the mean age was 17.0 years (+/-1.5 years), 53% were Caucasian, and 47% were African-American. Sixty-nine percent of participants reported vaginal douching, mostly for hygienic reasons (68%). Those reporting vaginal douching were more likely to have a history of sexual intercourse (P < 0.01) and a history of one or more sexually transmitted diseases (P < 0.05). Age of first douche correlated positively with age of first sexual intercourse (r = 0.34, P < 0.001). African-Americans did not douche to a greater degree than Caucasians. However, racial differences were noted in knowledge of and attitude toward vaginal douching. CONCLUSIONS: Vaginal douching was a common practice among adolescent females attending a public family planning clinic in a small southern city. Culturally appropriate educational strategies for African-American and Caucasian adolescent females should improve awareness of adverse events associated with vaginal douching, despite family and personal beliefs about this practice.

Vaginal douching in adolescents attending a family planning clinic

Background: One of the variables most consistently associated with vaginal douching is race, with African-American women douching more regularly. Sparse data exists in the medical literature about the practice of vaginal douching among adolescents. The purpose of this study was to assess the prevalence, knowledge, attitude, and practices of vaginal douching among adolescent females attending a public family planning clinic, and determine whether African-American (AA) females douche to a greater degree than Caucasian females.Methods: In this cross-sectional study, a one-page questionnaire was administered to all adolescent females (

Parietal cells express high levels of Na-K-2Cl cotransporter on migrating into the gastric gland neck.

Na-K-2Cl cotransport and Cl/HCO3 exchange are prominent mechanisms for Cl- uptake in Cl--secreting epithelial cells. We used immunofluorescence microscopy to delineate the distributions of Na-K-2Cl cotransporter-1 (NKCC1) and anion exchanger-2 (AE2) proteins in rat gastric mucosa (zymogenic zone). Parietal cells (PCs) above the neck of the gastric gland contained abundant AE2 but little or no NKCC1, whereas those in the neck and base contained high NKCC1 but diminished AE2. Lower levels of NKCC1 were detected in surface mucous cells and in cells comprising the blind ends of all glands. Pulse labeling of proliferating cells with bromodeoxyuridine indicated that new PCs originate in the isthmus with scant NKCC1; the subset of PCs that migrate downward expresses NKCC1 abruptly on entering the neck, within 7 days of cell division. Our results suggest that downwardly migrating PCs replace one mechanism for Cl- entry (Cl/HCO3 exchange) with another (Na-K-2Cl cotransport).

Is vertical vein ligation necessary in repair of total anomalous pulmonary venous connection?

BACKGROUND: In the repair of total anomalous venous connection, vertical vein ligation is recommended to eliminate left-to-right shunting. However, the small left heart chambers may not always tolerate the immediate increase in blood flow after combined repair and vein ligation. METHODS: A retrospective review of 23 infants and children undergoing correction of total anomalous pulmonary venous connection was undertaken to determine whether vertical vein ligation is a necessary component of successful surgical repair. In 14 patients this vein was ligated, whereas in 9 it was left patent. Six patients who underwent ligation and 5 who did not had pulmonary venous obstruction before operation. RESULTS: The operative mortality rate was 36% (5 of 14 patients) for the ligated group compared with 0% (0 of 9 patients) for the nonligated group (p = 0.06). All deaths occurred in patients with preoperative obstruction and a low mean left atrial pressure, and four of the deaths were directly attributable to left heart failure. Follow-up echocardiography in patients in whom the vertical vein was not ligated revealed adequate cardiac function and no residual left-to-right flow through the previously patent venous conduit. CONCLUSION: Vertical vein ligation during the repair of total anomalous pulmonary venous connection is not routinely necessary and actually may be undesirable in patients with preoperative obstruction, in whom the left heart chambers are particularly small.

Myosin light chain kinase phosphorylation in nitrovasodilator induced swine carotid artery relaxation.

Nitrovasodilators are hypothesized to induce smooth muscle relaxation by their metabolism to nitric oxide, which then activates soluble guanylyl cyclase, increases [cGMP], and activates cGMP-dependent protein kinase. cGMP-dependent phosphorylation is then proposed to decrease intracellular [Ca2+] ([Ca2+]i) and to reduce the Ca(2+)-sensitivity of contraction. We hypothesized that one component of decreased Ca(2+)-sensitivity, reduced Ca(2+)-sensitivity of MLC phosphorylation, was due to phosphorylation of myosin light chain kinase (MLCK) on the peptide site A. In the swine carotid artery, histamine (10 microM) stimulation increased aequorin-estimated [Ca2+]i, MLCK site A phosphorylation, MLC phosphorylation, and force. Subsequent addition of 100 microM nitroglycerin (NTG) or 100 microM sodium nitroprusside (NP) to histamine-stimulated tissues increased [cGMP], decreased both MLC phosphorylation and force, but did not significantly alter [cAMP], [Ca2+]i, or MLCK site A phosphorylation. Addition of NTG and NP alone to unstimulated tissues increased MLCK site A phosphorylation, but did not alter [Ca2+]i. In tissues preincubated with NP, subsequent histamine contraction was slowed compared with controls, however, this slowed rate of contraction appeared to result from an attenuation of histamine-dependent increases in [Ca2+]i. These data suggest that, in swine carotid artery, nitrovasodilators can decrease the Ca(2+)-sensitivity of MLC phosphorylation without increasing MLCK site A phosphorylation. Nitrovasodilators, per se, can induce site A MLCK phosphorylation, potentially by cGMP dependent activation of cAMP-dependent protein kinase.

Association of hypertrophic maxillary frenulum with hypoplastic left heart syndrome.

We report a previously unrecognized association between a hypertrophic frenulum separating the alveolar portion of the maxillary palatine suture with hypoplastic left heart syndrome in one fetus and seven children. A hypertrophic frenulum was not found in 25 pediatric cardiology patients without hypoplastic left heart syndrome. This finding may provide a marker for suspecting hypoplastic left heart syndrome in the neonate.

Cyclic nucleotide dependent relaxation in vascular smooth muscle.

Although not without controversy, the mechanisms inducing contraction of vascular smooth muscle are relatively well defined. There is a stimulus-induced increase in myoplasmic [Ca2+] with activation of myosin light chain kinase by the Ca(2+)-calmodulin complex, phosphorylation of the 20-kDa regulatory light chain of myosin, with subsequent cross-bridge cycling and force development. Ca(2+)-dependent phosphorylation of the myosin regulatory light chain appears to be the primary mechanism responsible for regulating stress in vascular smooth muscle. The relationship between myoplasmic [Ca2+] and myosin phosphorylation (i.e., the calcium sensitivity of phosphorylation) is regulated. It is higher with agonist stimulation than in tissues depolarized with high potassium solutions or after skinning procedures. The relationship between myosin phosphorylation and stress appears to be invariant with physiologic stimulation. This suggests that cross-bridge phosphorylation normally determines contraction. The mechanisms of relaxation are less well defined. In the most simple scheme, reduction of myoplasmic [Ca2+] with a fall in myosin light chain kinase activity would suffice to account for dephosphorylation of the regulatory light chain and relaxation. However, other mechanisms have been implicated in cyclic nucleotide dependent relaxation in vascular and other smooth muscle tissues. The current hypotheses of the mechanism of cyclic nucleotide dependent relaxation in vascular smooth muscle are reviewed.

Mechanisms of increased sensitivity to A2 adenosine receptor stimulation in immature rabbit aortic rings.

Adenosine receptor-mediated vasodilation is increased in immature vessels compared to mature vessels. To determine the mechanism of this increased sensitivity, isolated vascular rings from mature and immature rabbits were studied to evaluate the contribution of the endothelium and the contribution of adenosine-dependent 3',5'-cyclic monophosphate (cAMP) to adenosine receptor-mediated relaxation. Dose responses were measured in endothelial-intact and nonendothelialized aortic rings using 5'-(N-ethylcarboxamido)-adenosine (NECA), a nonhydrolyzable adenosine agonist. Immature rings were more sensitive to NECA than mature rings as demonstrated by a lower ED50 and steeper slope of the dose-response curve. There was no effect on endothelial removal in immature rings while there was a significant decrease in response in mature rings. Despite being more sensitive to NECA, immature rings had less increase in cAMP (percent change from basal level) at maximal vasodilation than mature rings although cAMP did not change in either age at the ED50. The lack of change with endothelial removal in immature vessels suggests that the endothelium is not involved in the increased sensitivity of immature rings to NECA. The cAMP data suggests that other mechanisms for vasodilation are important at the ED50 for NECA in both ages. Maximal vasodilation with NECA on the other hand was associated with increases in cAMP although they were lower in the immature rings.

Nitrovasodilators relax arterial smooth muscle by decreasing [Ca2+]i and uncoupling stress from myosin phosphorylation.

Elevations in guanosine 3',5'-cyclic monophosphate concentration ([cGMP]) are proposed to induce arterial smooth muscle relaxation by either 1) decreasing myoplasmic [Ca2+] ([Ca2+]i), 2) decreasing the [Ca2+]i sensitivity of phosphorylation, or 3) uncoupling force from myosin phosphorylation. We evaluated the importance of each of these mechanisms by measuring changes in [cGMP], aequorin- and fura-2-estimated [Ca2+]i, myosin light chain phosphorylation, and stress in histamine-stimulated swine carotid arteries. In tissues submaximally stimulated with 3 microM histamine, nitroprusside (NP) induced a proportional decrease in myoplasmic [Ca2+] and myosin phosphorylation, suggesting that the relaxation was at least partially induced by decreases in [Ca2+]i without a change in the [Ca2+]i sensitivity of phosphorylation. In tissues maximally stimulated with 10 microM histamine, NP and nitroglycerin produced significant relaxations that were not associated with significant sustained reductions in [Ca2+]i or myosin phosphorylation. With both submaximal and maximal histamine stimulation, nitrovasodilators produced more substantial relaxation than that expected from the nitrovasodilator-induced reduction in myosin phosphorylation. These results suggest that nitrovasodilators relax histamine-stimulated swine arterial smooth muscle by at least two mechanisms: 1) reducing [Ca2+]i, an effect observed in submaximally stimulated tissues, and 2) uncoupling of stress from myosin phosphorylation.

Cyclic AMP relaxes swine arterial smooth muscle predominantly by decreasing cell Ca2+ concentration.

1. Our objective was to evaluate the mechanism of cyclic AMP-dependent arterial smooth muscle relaxation. Cyclic AMP-dependent relaxation has been proposed to result from either (a) a decrease in intracellular [Ca2+] or (b) a decrease in [Ca2+] sensitivity of myosin light chain kinase by protein kinase A-dependent phosphorylation of myosin kinase. 2. We evaluated these proposed mechanisms by examining forskolin-induced changes in aequorin-estimated myoplasmic [Ca2+], [cyclic AMP], myosin phosphorylation and stress generation in agonist-stimulated or KCl-depolarized swine common carotid media tissues. 3. Forskolin, an activator of adenylyl cyclase, increased [cyclic AMP] and reduced [Ca2+], myosin phosphorylation and stress in tissues pre-contracted with phenylephrine or histamine. This relaxation was not associated with an alteration of the [Ca2+] sensitivity of phosphorylation, nor the dependence of stress on phosphorylation. 4. Forskolin pre-treatment attenuated, but did not abolish, agonist-induced increases in [Ca2+] and stress. 5. These results suggest that cyclic AMP-induced relaxation of the agonist-stimulated swine carotid media is primarily caused by cyclic AMP-mediated decreases in myoplasmic [Ca2+].

Progression of cardiac disease in Emery-Dreifuss muscular dystrophy.

Emery-Dreifuss muscular dystrophy (EDMD) is a rare X-linked muscular dystrophy characterized by early contractures, progressive muscle weakness, and atrial arrhythmias. Recent reports suggest that there may be additional cardiac problems in affected males and that carrier females may also show ECG abnormalities. We restudied two large families with EDMD in order to determine the extent of these problems. We examined 10 affected males and interviewed 2 others. The 3 affected males less than 20 years old had no ECG changes. All affected men of 35 years or older had arrhythmias. One had more severe arrhythmias when asleep, indicating the usefulness of continuous 24-h ECG monitoring in the evaluation of males affected with EDMD. Two required pacemakers, 4 had already had a pacemaker placed, and 4 other affected men with pacemakers had died prior to this study. One affected man with a pacemaker developed ventricular bigeminy and another developed congestive heart failure. Thus of 10 affected males with pacemakers, 6 had additional cardiac symptoms and 4 have died. Males with EDMD may survive longer with a ventricular pacemaker, but this may increase the likelihood that they will develop cardiomyopathy and ventricular arrhythmias. Of 34 carrier females examined, 6 had arrhythmias typical of EDMD. Two required a pacemaker. The risk of arrhythmia increased with age. Results from one family should be extrapolated to another with caution, as there appears to be significant interfamilial variation. We suggest careful cardiologic follow-up of EDMD patients and regular cardiac evaluations for older carrier females.

Intrapericardial teratoma causing nonimmune hydrops fetalis and pericardial tamponade: a case report.

A case of fetal anasarca secondary to an intrapericardial teratoma is reported. The clinical, echocardiographic, and histologic features are described, along with a review of intrapericardial lesions.

Repair of large muscular ventricular septal defects in infants employing left ventriculotomy.

The approach to muscular ventricular septal defect has been controversial. Traditional approaches have included pulmonary artery banding or right ventriculotomy. Left ventriculotomy has been employed in older children because of the ease of exposure in the absence of trabeculations, but concern has been raised regarding potential loss of left ventricular function. Four infants less than 4 months of age underwent repair of a large muscular ventricular septal defect by left ventriculotomy. One infant had no associated defects; 2 had undergone previous coarctation repair (1 with pulmonary artery banding); and 1 had a large secundum atrial septal defect. All had congestive heart failure refractory to maximal medical management. All patients survived, and there was no myocardial dysfunction. Echocardiographic indices of ventricular function 3 to 24 months postoperatively were normal (mean shortening fraction, 32.5%). Left ventriculotomy with patch closure of the ventricular septal defect provides a simple approach to a large muscular ventricular septal defect in infants with heart failure.

Internal consistency of echocardiographic estimates of the severity of left ventricular outflow obstruction.

To determine their internal consistency, M-mode and Doppler echocardiography were used to estimate the gradient across the left ventricular outflow tract during 74 evaluations of 50 infants, children, and young adults with congenital valvular (n = 43), subvalvular (n = 6), and supravalvular (n = 1) aortic stenosis. By M-mode the gradient was estimated from the wall-stress formula (left ventricular pressure = 225 x wall thickness/end-systolic diameter) minus systolic blood pressure determined by sphygmomanometry. Doppler (pulsed or continuous wave) methods utilized the Bernoulli formula (gradient = 4 x V2). There was good agreement between the M-mode and Doppler estimates of outflow gradient in most patients (r = 0.69, standard error of the estimate = 26.9). In 46 of 74 comparisons (62%) the two estimates differed by less than 20 mm Hg, and the estimates placed the patient in the same clinical class (mild, moderate, or severe). In 22 patients undergoing cardiac catheterization, there was only a fair correlation between the M-mode (r = 0.50) and Doppler (r = 0.58) gradients and those obtained at catheterization. Each noninvasive technique yielded major overestimates or underestimates of the gradient in several instances. The M-mode and Doppler techniques for estimating the severity of congenital aortic stenosis are complementary. Their combined use minimizes but does not totally eliminate errors of overestimation or underestimation of outflow gradient.