Morphology of ventricular septal defect associated with coarctation of aorta.

It is now well established that the morphology of the ventricular septal defect associated with interrupted aortic arch is such as to compromise blood flow to the ascending aorta. Though there is some evidence that a similar mechanism may be operative in coarctation with ventricular septal defect, we are unaware of any necropsy study of this hypothesis. We therefore studied 25 hearts from the Heart Museum of Children's Hospital of Pittsburgh with coarctation and ventricular septal defect. Four had a malalignment defect with left ventricular outflow tract obstruction such as is seen in cases with interruption. Twenty of the remaining cases had a particular form of perimembranous defect with aortic overriding. The defects were partially closed by tricuspid valve tissue, the left ventricular outflow tract being further narrowed by various anatomical lesions. In addition, mitral valve malformations were present in 14 cases. The anatomy of the group as a whole suggests a possible reduction of aortic blood flow during fetal development. The clinical implications of these findings remain to be evaluated.     

The relationship between CR3 deficiency and neutrophil actin assembly

Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency.     

Anti-CS1 humanized monoclonal antibody HuLuc63 inhibits myeloma cell adhesion and induces antibody-dependent cellular cytotoxicity in the bone marrow milieu

Currently, no approved monoclonal antibody (mAb) therapies exist for human multiple myeloma (MM). Here we characterized cell surface CS1 as a novel MM antigen and further investigated the potential therapeutic utility of HuLuc63, a humanized anti-CS1 mAb, for treating human MM. CS1 mRNA and protein was highly expressed in CD138-purified primary tumor cells from the majority of MM patients (more than 97%) with low levels of circulating CS1 detectable in MM patient sera, but not in healthy donors. CS1 was expressed at adhesion-promoting uropod membranes of polarized MM cells, and short interfering RNA (siRNA) targeted to CS1 inhibited MM cell adhesion to bone marrow stromal cells (BMSCs). HuLuc63 inhibited MM cell binding to BMSCs and induced antibody-dependent cellular cytotoxicity (ADCC) against MM cells in dose-dependent and CS1-specific manners. HuLuc63 triggered autologous ADCC against primary MM cells resistant to conventional or novel therapies, including bortezomib and HSP90 inhibitor; and pretreatment with conventional or novel anti-MM drugs markedly enhanced HuLuc63-induced MM cell lysis. Administration of HuLuc63 significantly induces tumor regression in multiple xenograft models of human MM. These results thus define the functional significance of CS1 in MM and provide the preclinical rationale for testing HuLuc63 in clinical trials, either alone or in combination.     

Cerebrospinal fluid corticotropin-releasing hormone in healthy humans: effects of yohimbine and naloxone

CRH neurons projecting from the paraventricular nucleus (PVN) of the hypothalamus to the median eminence control hypothalamic-pituitary-adrenal (HPA) axis activity. However, CRH neurons outside the PVN as well as PVN neurons projecting to sites other than the median eminence also contribute to the stress response and may play a role in mood and anxiety disorders. We have attempted to investigate possible noradrenergic and opioid regulation of these non-HPA CRH neurons. We hypothesized that yohimbine (an alpha2-adrenergic antagonist) would have stimulatory action on non-HPA CRH neurons, whereas naloxone (a mu-opioid receptor antagonist) would not have this effect. Adult normal volunteers received i.v. yohimbine (n = 5; 0.4 microg/kg), naloxone (n = 4; 125 microg/kg), or placebo (n = 3; 0.9% saline). Cerebrospinal fluid (CSF) was collected continuously, and concentrations of CSF CRH, CSF norepinephrine (NE), and plasma cortisol were measured. Administration of either yohimbine or naloxone caused significant increases in plasma cortisol concentrations over time. Although yohimbine robustly increased CSF NE levels and appeared to increase CSF CRH levels, these effects were not seen after naloxone or placebo administration. Intraindividual correlations were not observed between the measured concentrations of plasma cortisol and CSF CRH for any of the subjects. The results support the idea that CSF CRH concentrations reflect the activity of non-HPA CRH neurons. Although both yohimbine and naloxone stimulated the HPA axis, only yohimbine appeared to have stimulatory effects on central NE and non-HPA CRH.     

Colorectal Stenting for Malignant and Benign Disease: Outcomes in Colorectal Stenting

INTRODUCTION: Self-expanding metal stents are now an established treatment for malignant colonic obstruction. Favorable outcomes have been reported both for cancer palliation and treatment of acute obstruction as a bridge to surgery. However, little data exists regarding the use of stents for benign colonic obstruction.METHODS: All cases of colonic stent insertion occurring between December 1996 to October 2002 were reviewed. During the study period, 36 patients with malignant obstruction and 6 patients with benign obstructive disease underwent placement of self-expandable stents using a combined endoscopic and fluoroscopic technique.RESULTS: Stent placement was successful in 36 of 42 patients (86 percent). Complications occurred in 16 of 36 patients (44 percent): migration (n = 7), reobstruction (n = 5), perforation (n = 2), fistula formation (n = 1), and stent fracture (n = 1). Stent placement was successful in 100 percent of patients with benign strictures but poststent migration was frequent (2/6).CONCLUSIONS: Stent insertion provided an effective outcome in patients with malignant colonic obstruction as a palliative and preoperative therapy. Although a relatively high migration rate was observed in patients with benign strictures, stenting was still effective in providing luminal patency (median follow-up, 7.5 months). Stenting should be considered as a first-line treatment for malignant strictures and as a potential therapy for selected benign strictures.