Myocardial siderosis due to hemochromatosis in an individual with hypertrophic cardiomyopathy

A patient with hypertrophic cardiomyopathy (HCM) and transfusion-dependent sideroblastic anemia, who presented with decompensated heart failure, is described. The present case demonstrates the usefulness of cardiac magnetic resonance imaging as a noninvasive imaging modality to assess the etiology of new systolic dysfunction in the setting of HCM. Cardiac magnetic resonance imaging is able to differentiate between the dilated ‘burned-out’ phase of HCM and a concomitant dilated cardiomyopathy secondary to myocarditis or hemosiderosis.     

PapD-like chaperones provide the missing information for folding of pilin proteins

A fundamental question in molecular biology is how proteins fold into domains that can serve as assembly modules for building up large macromolecular structures. The biogenesis of pili on the surface of Gram-negative bacteria requires the orchestration of a complex process that includes protein synthesis, folding via small chaperones, secretion, and assembly. The results presented here support the hypothesis that pilus subunit folding and biogenesis proceed via mechanisms termed donor strand complementation and donor strand exchange. Here we show that the steric information necessary for pilus subunit folding is not contained in one polypeptide sequence. Rather, the missing information is transiently donated by a strand of a small chaperone to allow folding. Providing the missing information for folding, via a 13-amino acid peptide extension to the C-terminal end of a pilus subunit, resulted in the production of a protein that no longer required the chaperone to fold. This mechanism of small periplasmic chaperone function described here deviates from classical hsp60 chaperone-assisted folding.     

Meningitis and midline facial deformity

A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.     

Feto-placental steroid metabolism in growth retarded human fetuses

The goal of the study was the determination of the relative roles of the placenta and the fetus in causing low serum estriol (E3) levels in women bearing fetuses with intrauterine growth retardation (IUGR). Umbilical venous levels of E3 and dehydroepiandrosterone sulfate (DHAS) were measured in 31 samples from fetuses with IUGR, 21 of whom were vaginally delivered and 10 who were delivered by cesarean section. In addition, estrone (E1) and estradiol (E2) were measured in 11 of the samples. The results were compared with 11 samples from cesarean section delivered control term infants and 54 samples from vaginally delivered control infants. The vaginally delivered IUGR group had a significantly lower mean umbilical venous DHAS level than did their control group (2128 +/- 158 ng/ml SEM versus 2645 +/- 130, p less than 0.05). Both the vaginally delivered and cesarean section delivered IUGR infants had umbilical venous E3 levels significantly lower than in their control groups (70 +/- 10 ng/ml SEM versus 144 +/- 10, p less than 0.001, and 46 +/- 11 ng/ml SEM versus 136 +/- 23, p less than .01, respectively). Umbilical venous E1 and E2 levels were not different from the control values. E1, E2, E3, and DHAS were measured in eight maternal venous samples obtained from mothers bearing fetuses with IUGR. In comparison with 11 control mothers, only E3 was significantly different (10.7 +/- 3.0 ng/ml SEM in mothers with IUGR fetuses versus 25.0 +/- 4.9 in control mothers p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Magnetic resonance imaging to determine the distribution of a vaginal gel: before,during, and after both simulated and real intercourse

To provide effective contraception and protection against sexually transmitted disease, vaginal gels should maximally cover the cervical os and the vaginal epithelium before, during and after intercourse. To non-invasively monitor the intravaginal distribution of an applied intravaginal gel, we performed high-resolution magnetic resonance imaging (MRI) of the female pelvis before, during and after both real and simulated sexual intercourse. We sought to determine whether simulated intercourse with a plastic phallus could be used as a surrogate for real intercourse for such experiments.

Dilute gadolinium chelate solution was mixed with Gynol-II gel and introduced intravaginally to volunteer female human subjects using a conventional applicator. MRI was performed at 1.5 Tesla with a surface coil. Imaging of the female pelvis was performed: (1) immediately after insertion of the gel; (2) during real intercourse with a male partner (2 subjects) or simulated intercourse with a plastic phallus (4 subjects); and (3) after completion of real or simulated intercourse. Subjects were studied after application of both 3 mL and 5 mL of vaginal gel. Measurements of gel thickness covering the vaginal mucosa were made digitally using electronic calipers.

The bolus of gel is initially located in the upper vaginal canal, superior to the urogenital diaphragm. Both real and simulated intercourse dramatically increases the spread of gel to the lower vagina. The cervix appears to be adequately covered with gel both before and after intercourse. Increasing the volume of the gel increases initial vaginal mucosal coverage but also increases leakage from the introitus. No statistically significant differences in vaginal mucosal coverage were found between patients having undergone real vs. simulated intercourse, or on post-intercourse scans of 3 mL versus 5 mL. MRI is a sensitive, reproducible means of tracking the spread of intravaginal medications.