Coronary bifurcation lesions.

Coronary bifurcations are prone to develop atherosclerotic plaque due to turbulent blood flow and high shear stress. These lesions amount to 15-20% of the total number of interventions. The true bifurcation lesion consist of >50% diameter obstruction of the main vessel (MV) and of the side branch (SB) in an inverted "Y" fashion. Treatment of coronary bifurcation lesions represents a challenging area in interventional cardiology but recent advances in percutaneous coronary interventions (PCI) have led to the dramatic increase in the number of patients successfully treated percutaneously. When compared with non-bifurcation interventions, bifurcation interventions have a lower rate of procedural success, higher procedural costs, longer hospitalization and a higher clinical and angiographic restenosis. Introduction of drug-eluting stents (DES) has resulted in a lower event rate and reduction of main vessel (MV) restenosis in comparison with historical controls. However, side branch (SB) ostial residual stenosis and long-term restenosis remains a problem. Although stenting the MV with provisional SB stenting seems to be the prevailing approach, in the era of DES various two-stent techniques have emerged to allow stenting of the large side branch.

Electronic and atomic shell structure in aluminium nanowires.

We report experiments on aluminium nanowires in ultra-high vacuum at room temperature that reveal a periodic spectrum of exceptionally stable structures. Two 'magic' series of stable structures are observed: at low conductance, the formation of stable nanowires is governed by electronic shell effects whereas for larger contacts atomic packing dominates. The crossover between the two regimes is found to be smooth. A detailed comparison of the experimental results to a theoretical stability analysis indicates that, while the main features of the observed electron-shell structure are similar to those of alkali and noble metals, a sequence of extremely stable wires plays a unique role in aluminium. This series appears isolated in conductance histograms and can be attributed to 'superdeformed' non-axisymmetric nanowires.

Preduodenal portal vein causing duodenal obstruction associated with situs inversus, intestinal malrotation, and polysplenia: A case report.

Preduodenal portal vein (PDPV) is a rare anomaly described in only 82 patients in the literature. In a few patients, the PDPV was the direct cause of duodenal obstruction. The authors have treated a newborn with PDPV associated with total situs inversus, intestinal malrotation and polysplenia who presented clinically with duodenal obstruction.

Unusual presentation of psoas abscess in a child.

Primary abscess of the psoas muscle is relatively rare in infants and young children. The clinical presentation of the disease, with limping, fever, and abdominal pain, may be confused with conditions such as septic arthritis of the hip, osteomyelitis, or appendicitis. The authors present an unusual case of a ruptured left psoas abscess presenting as generalized peritonitis in a child. J Pediatr Surg 36:1859-1860.

Angiotensin AT1 receptor antagonist irbesartan decreases lesion size, chemokine expression, and macrophage accumulation in apolipoprotein E-deficient mice.

Recent data suggest that angiotensin II AT1 receptor antagonists may be beneficial in the treatment of atherosclerosis. To clarify how AT1 receptor antagonists reduce atherosclerosis, the effect of irbesartan on atherosclerotic lesion development was determined in low-fat, chow-fed apolipoprotein (Apo) E-deficient mice. Irbesartan (50 mg/kg per day) strongly decreased lesion development after a 12-week treatment period (lesion size: irbesartan treated, 20,524 +/- 4,200 microm(2) vs. control, 99,600 +/- 14,500; 79.4% inhibition, p < 0.001). This effect was not due to an effect of irbesartan on lipoprotein levels because irbesartan slightly increased total cholesterol levels and decreased the ratio of Apo A-I relative to Apo B levels. Immunochemical analysis of the atherosclerotic lesions using the mac3 monoclonal antibody showed the presence of macrophages in the lesions of control mice, whereas sections from irbesartan-treated animals only showed occasional labeling in the lesion area. These data suggest that irbesartan inhibits monocyte/macrophage influx into the vessel wall. Therefore, expression levels of monocyte chemoattractant protein-1 (MCP-1), as well as other chemokines involved in macrophage infiltration into the lesion area, were measured in the aortic sinus of control and irbesartan-treated animals. Irbesartan treatment strongly decreased MCP-1 mRNA levels as well as MCP-1 immunostaining in the lesion area. This effect of irbesartan on MCP-1 occurred without an effect on CCR2, the receptor of MCP-1. Expression of macrophage inflammatory protein (MIP)-1alpha, another CC chemokine expressed in atherosclerotic lesions, was also reduced after irbesartan treatment, without effect on CCR3 and CCR5, the receptors of MIP-1alpha. Concomitantly, the expression of the angiogenic chemokines KC and MIP-2, which are functionally related to interleukin-8, were downregulated, whereas their shared receptor CXCR2 was upregulated. These data suggest that inhibition of the inflammatory component of lesion progression plays an important role in the inhibitory effect of AT1 receptor antagonists on atherosclerotic lesion formation.

Peritoneal encapsulation: a rare cause of bowel obstruction in children.

Two rare cases of peritoneal encapsulation causing partial intestinal obstruction are described. Both were operated on, and one of them had a "cocoonlike" appearance. The characteristics and differences of peritoneal encapsulation and abdominal cocoon are discussed.

Hoptel equalizes length of stay for homeless and domiciled inpatients.

BACKGROUND: There is growing evidence that homeless individuals have longer inpatient lengths of stay with significantly higher medical costs than domiciled individuals. We compared adjusted mean lengths of stay among domiciled patients and homeless patients discharged to a hospital hotel (hoptel). Because the hoptel allowed homeless patients to be discharged when medically indicated, we hypothesized no significant differences in lengths of stay between the 2 groups after adjustment for severity of illness. METHODS: Demographic, diagnosis, and length of stay data were obtained for all patients discharged from all inpatient wards at a large, urban Veterans Affairs Medical Center during the first 32 months of hoptel operation (1996 through 1998). Adjusted mean lengths of stay for domiciled patients and homeless patients discharged to the hoptel were compared. ANCOVA was used to adjust for demographic characteristics (age, income, race/ethnicity), diagnosis-related group (DRG), principal diagnosis, and substance abuse comorbidity. Three types of hospitalizations were analyzed on the basis of major DRG categories: general medical, psychiatric, and all hospitalizations. RESULTS: No significant differences were found in adjusted mean lengths of stay between domiciled patients and homeless patients discharged to the hoptel. Homeless hoptel patients stayed an average 0.7, 0.3, and 0.4 days longer than domiciled patients for all, general medical, and psychiatric hospitalizations (P = 0.504, 0.627, and 0.839), respectively. CONCLUSIONS: These data suggest that hoptels may help equalize inpatient lengths of stay among domiciled and homeless patients discharged to a hoptel. Public health care systems seeking innovative ways of reducing inpatient lengths of stay among homeless patients ought to consider establishing hoptels.

Unusual presentation of omphalomesenteric duct remnant: a variant of mesodiverticular band causing intestinal obstruction.

Two unusual cases of small bowel obstruction associated with an omphalomesenteric duct remnant are described in 2 girls aged 14 years. The causative factor was a stenotic area in the terminal ileum caused by a ringlike lipovascular mesenteric band encroaching externally on the lumen. A phytobezoar was lodged proximally. This is as yet an undescribed variant of a mesodiverticular band.

Traumatic avulsion of kidney into the chest through a ruptured diaphragm in a boy.

This report presents a case of a teenage patient who survived following severe blunt trauma with complete avulsion of the right kidney into the chest through a ruptured diaphragm. The combination of kidney avulsion into the chest is extremely rare. Only three similar cases have been reported in the English literature to date (1-3).

Reducing psychiatric hospitalization among mentally ill veterans living in board-and-care homes.

OBJECTIVE: The effectiveness of a community-based case management program at the Veterans Affairs West Los Angeles Healthcare Center in reducing hospital readmission of mentally ill veterans living in privately operated board-and-care homes was evaluated. METHODS: A retrospective cohort design was used. The sample consisted of 321 patients identified by hospital records as living in one of 24 board-and-care homes in the Los Angeles area that were approved by the community residential care program. A total of 214 subjects who received monthly home visits from case managers (program group) were compared with 107 subjects who did not receive monthly home visits (comparison group). The median number of psychiatric bed-days used was calculated for the two years before and after follow-up. The number of days from the start of follow-up to the first psychiatric hospitalization was also calculated. RESULTS: Among subjects in the program group, the median number of psychiatric bed-days used decreased significantly, from 59 days to 50 days. No significant change in the median number was observed for comparison subjects. Comparison subjects were rehospitalized 1.7 times more often than program subjects. Overall, program subjects under age 62 (younger subjects) were rehospitalized 2.5 times more often than older subjects. In the program group, those who had received home visits for more than two years were hospitalized three times more often than those who had received visits for less than two years, and younger subjects were rehospitalized 1.8 times more often than older subjects. CONCLUSIONS: The findings suggest that home visits conducted by case managers in a community residential care program helped reduce psychiatric hospitalization among veteran patients living in privately operated board-and-care homes.

Nissen fundoplication and Boix-Ochoa antireflux procedure: comparison between two surgical techniques in the treatment of gastroesophageal reflux in children.

Over a period of 19 years an antireflux procedure was performed for gastroesophageal reflux in 59 children. Thirty-two patients underwent Nissen fundoplication and 27 children underwent the Boix-Ochoa antireflux procedure. Six patients died between two and 15 months post surgery of unrelated causes. Follow-up period from six months to 18 years was available in 45 (85%) of the surviving patients. This report summarizes the complications and long-term results with the two surgical procedures and their comparisons. The follow-up evaluation included parental interview and physical examination. Upper GI series and pH monitoring were performed only in children with signs and symptoms of recurrent GER or other post-operative complications. At follow-up with a mean period of 8.7 years following Nissen fundoplication, 87.5% showed good results without any residual symptoms. However, the overall complication rate was as high as 50%. Following the Boix-Ochoa antireflux procedure, 17 (81%) children showed excellent results while four children had recurrent GER. This occurred in two neurologically impaired children and two patients following esophageal atresia repair. No other post-operative complications were encountered with the Boix-Ochoa antireflux procedure. In our experience, the Boix-Ochoa antireflux procedure should be the procedure of choice in the surgical treatment of GER in otherwise normal children while the Nissen fundoplication is preferable in neurologically impaired children and in patients with GER following esophageal atresia repair.

Granular cell tumor (myoblastoma) of the labia major: a rare benign tumor in childhood.

The clinical presentation, surgical findings, and histology of a granular cell tumor (myoblastoma) of the vulva in a 9-year-old girl are presented. Although rare, this benign lesion must be considered in the differential diagnosis of the labia major masses, such as Bartholin's duct cyst, lipoma, papilloma, hydradenoma, and fibroma.

Near total intestinal aganglionosis with extreme short-bowel syndrome--a difficult surgical dilemma.

Forty cases of total or near-total intestinal agangliosis (NTIA) were described to date in the English literature. Most cases had a lethal outcome. We describe the 41st case--a Beduin male neonate--who had only 30 cm of proximal hypoganglionic jejunum. He is presently almost one-year-old and thriving on home TPN, receiving one quarter of his caloric requirements orally using pregestamil, an MCT formula. The initial intricate course, diagnosis and several operative procedures, are elaborated. A review of the scant literature is discussed. The elusiveness of the correct diagnosis is pointed out and means to overcome these errors are described. Various surgical procedures have been suggested, none of which offer the perfect solution to the severe basic problem of short bowel. Long-term parenteral hyperalimentation is still the main modality of treatment. Based on our modest experience, we suggest saving every possible length of jejunum, even if hypoganglionic, since this bowel, following a few weeks of adaptation, starts to function fairly well, suggesting perhaps some neuro-muscular maturation. The best surgical approach is still pending. We present a report of a child with this disease and discuss the therapeutic dilemma.

Comparative experimental study of esophageal wall regeneration after prosthetic replacement.

This study compares three prosthetic materials for potential use in patching and bridging congenital and acquired esophageal defects. The study was divided into two parts. In the first part, full-thickness, 6-cm2 cervical esophageal defects were induced in three groups of young mongrel dogs and were replaced with patches of lyophilized dura mater (Lyodura), polyethylene terephthalate (Dacron), or expanded polytetrafluoroethylene (PTFE). The dogs in the Lyodura subgroup were scheduled to be sacrificed after 1, 2, 4, 8, and 12 weeks and the dogs in the PTFE and Dacron subgroups were sacrificed after 1, 2, 3, 4, 6, and 7 months. The patched esophagus was removed for gross and microscopic examination. In the second part of the study a segment of the esophagus was excised in another three groups of dogs and replaced with 3 x 2 cm tubes of Lyodura, Dacron, or PTFE. Here the follow-up was prolonged and included radiological, endoscopic, and histological assessment. The dogs of each subgroup were scheduled to be sacrificed after 6, 8, and 12 months. Results indicated that lyophilized dura mater covered and neoepithelialized the patched area within the shortest period of time without foreign body reaction and with only slight collagen deposit, resulting in a ductile repaired esophageal wall. Therefore, its use may be considered for replacement of partial esophageal defects. For complete circumferential defects, the present study and our review of the literature showed that there is as yet no ideal prosthetic material that promotes good incorporation but is not prone to stenosis. Further studies in this area are required.

Familial idiopathic intussusception: a report of two families.

The authors report on two families with 5 out of 10 and two of two siblings who presented with idiopathic ileocolic intussusception. This may suggest hereditary predisposition as an etiologic factor.

Relaxant effect of 2-methyl-thio-adenosine diphosphate on rat thoracic aorta: effect of clopidogrel.

The main aim of this study was to determine the functional effect of 2-methyl-thio-adenosine diphosphate (2MeS-ADP) on vascular purinoceptors, in comparison with that of a characterised agonist of the P2Y1 receptor, 2-methyl-thio-adenosine triphosphate (2MeS-ATP), and of the P2Y2 receptor, uridine triphosphate (UTP). On phenylephrine-precontracted rat aortic rings, mounted isometrically in organ baths, we found that 2MeS-ADP (10(-9) to 10(-6) M) induced concentration-dependent relaxation of rings with a functional endothelium. Mechanical removal of the endothelium abolished the relaxant effect of 2MeS-ADP. The 2MeS-ADP-induced relaxation of phenylephrine-precontracted rings was inhibited by Nomega-nitro-L-arginine methyl ester (L-NAME) (100 microM) but not by indomethacin (100 microM) or aspirin (1 mM), indicating that the 2MeS-ADP-induced relaxation was nitric oxide (NO) synthase-mediated but not cyclooxygenase-dependent. Repeated stimulation with 2MeS-ADP resulted in desensitisation of the receptor. Under these conditions, the relaxant effect of 2MeS-ATP was abolished. On the contrary, UTP-induced relaxation was not affected, showing that 2MeS-ADP and 2MeS-ATP but not UTP shared the same receptor. Suramin (100 microM), a non-specific P2 inhibitor, abolished the effect of 2MeS-ADP, 2MeS-ATP and UTP. In contrast, pyridoxal-phosphate-6-azophenyl-2'-4'-disulphonic acid (PPADS) and adenosine-3'-phosphate-5'-phosphosulphate (A3P5PS) abolished only the vasodilator responses to 2MeS-ADP and 2MeS-ATP and did not affect the relaxant effect of UTP, showing that 2MeS-ADP acted through the P2Y1 receptor. Clopidogrel, a potent platelet ADP receptor antagonist, at a dose that strongly inhibited ADP-induced platelet aggregation ex vivo, did not modify the relaxant responses to 2MeS-ADP or 2MeS-ATP. In conclusion, these results showed that 2MeS-ADP induces endothelium-dependent, NO-mediated relaxation of rat aortic rings. This effect, resistant to clopidogrel treatment, occurred through activation of the P2Y1 receptor.