Spectrum of clinicopathologic manifestations of arrhythmogenic right ventricular cardiomyopathy/dysplasia: a multicenter study

OBJECTIVES: The aim of the present investigation was to redefine the clinicopathologic profile of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC), with special reference to disease progression and left ventricular (LV) involvement. BACKGROUND: Long-term follow-up data from clinical studies indicate that ARVC is a progressive heart muscle disease that with time may lead to more diffuse right ventricular (RV) involvement and LV abnormalities and culminate in heart failure. METHODS: Forty-two patients (27 male, 15 female; 9 to 65 years old, mean [+/-SD] age 29.6 +/- 18) from six collaborative medical centers, with a pathologic diagnosis of ARVC at autopsy or heart transplantation, and with the whole heart available, were studied according to a specific clinicomorphologic protocol. RESULTS: Thirty-four patients died suddenly (16 during effort); 4 underwent heart transplantation; 2 died as a result of advanced heart failure; and 2 died of other causes. Sudden death was the first sign of disease in 12 patients; the other 30 had palpitations, with syncope in 11, heart failure in 8 and stroke in 3. Twenty-seven patients experienced ventricular arrhythmias (ventricular tachycardia in 17), and 5 received a pacemaker. Ten patients had isolated RV involvement (group A); the remaining 32 (76%) also had fibrofatty LV involvement that was observed histologically only in 15 (group B) and histologically and macroscopically in 17 (group C). Patients in group C were significantly older than those in groups A and B (39 +/- 15 years vs. 20 +/- 8.8 and 25 +/- 9.7 years, respectively), had significantly longer clinical follow-up (9.3 +/- 7.3 years vs. 1.2 +/- 2.1 and 3.4 +/- 2.2 years, respectively) and developed heart failure significantly more often (47% vs. 0 and 0, respectively). Patients in groups B and C had warning symptoms (80% and 87%, respectively, vs. 30%) and clinical ventricular arrhythmias (73% and 82%, respectively, vs. 20%) significantly more often than patients in group A. Hearts from patients in group C weighed significantly more than those from patients in groups A and B (500 +/- 150 g vs. 328 +/- 40 and 380 +/- 95 g, respectively), whereas hearts from both group B and C patients had severe RV thinning (87% and 71%, respectively, vs. 20%) and inflammatory infiltrates (73% and 88%, respectively, vs. 30%) significantly more often than those from group A patients. CONCLUSIONS: LV involvement was found in 76% of hearts with ARVC, was age dependent and was associated with clinical arrhythmic events, more severe cardiomegaly, inflammatory infiltrates and heart failure. ARVC can no longer be regarded as an isolated disease of the right ventricle.     

Coenzyme-A-dependent esterification of cholesterol in rat intestinal mucosa

Rat intestinal mucosa contains an enzyme which catalyses the esterification of cholesterol. The enzyme is CoA-dependent and probably an acyl-CoA: cholesterol acyltransferase (ACAT) (E.C.2.3.1.26). Maximal activity in vitro is obtained when long chain acylcarnitines, CoA and carnitine palmityltransferase are used as an acyl-CoA generating system. The enzyme is localized in the microsomal fraction, has a pH optimum between 6.4-7.2, and oleate is the preferred acyl group. The activity of the enzyme is highest in the proximal jejunum, and has a capacity that can account for all cholesteryl esters found in intestinal rat lymph.     

Colour duplex ultrasonography in the rational management of chronic venous leg ulcers

Colour duplex ultrasonographic imaging has largely replaced venography in the assessment of lower-limb venous disorders. This is a study of the use of duplex in the management of patients with chronic venous ulceration in community ulcer clinics. Patients with chronic leg ulceration and an ankle: brachial pressure index of 0.85 or greater were studied. Assessment of venous competence in both the deep and superficial systems of the affected and unaffected legs was performed using colour venous duplex imaging. Reflux was defined as reverse flow for greater than 1 s after manual calf compression. One hundred consecutive patients were assessed over 15 months. Of 111 ulcerated legs, 96 had active ulceration, while 15 had been ulcerated within the previous 6 months. Fifty-seven (51 per cent) of the 111 ulcerated legs had superficial incompetence alone (88 per cent long saphenous system or its perforators, 12 per cent short saphenous system). Six legs (5 per cent) had isolated deep venous incompetence. Forty-two legs had mixed superficial and deep venous reflux; 22 of these had undergone previous venous surgery. Colour venous duplex assessment demonstrated superficial venous disease in approximately half of limbs with chronic leg ulceration. Venous dysfunction in these patients is potentially curable by surgery.     

The paternal effect gene ms(3)sneaky is required for sperm activation and the initiation of embryogenesis in Drosophila melanogaster

Calcium sensor proteins translate transient increases in intracellular calcium levels into metabolic or mechanical responses, by undergoing dramatic conformational changes upon Ca2+ binding. A detailed analysis of the calcium binding-induced conformational changes in the representative calcium sensors calmodulin (CaM) and troponin C was performed to obtain insights into the underlying molecular basis for their response to the binding of calcium. Distance difference matrices, analysis of interresidue contacts, comparisons of interhelical angles, and inspection of structures using molecular graphics were used to make unbiased comparisons of the various structures. The calcium-induced conformational changes in these proteins are dominated by reorganization of the packing of the four helices within each domain. Comparison of the closed and open conformations confirms that calcium binding causes opening within each of the EF-hands. A secondary analysis of the conformation of the C-terminal domain of CaM (CaM-C) clearly shows that CaM-C occupies a closed conformation in the absence of calcium that is distinct from the semi-open conformation observed in the C-terminal EF-hand domains of myosin light chains. These studies provide insight into the structural basis for these changes and into the differential response to calcium binding of various members of the EF-hand calcium-binding protein family. Factors contributing to the stability of the Ca2+-loaded open conformation are discussed, including a new hypothesis that critical hydrophobic interactions stabilize the open conformation in Ca2+ sensors, but are absent in "non-sensor" proteins that remain closed upon Ca2+ binding. A role for methionine residues in stabilizing the open conformation is also proposed.     

Diagnosis of vasa previa with endovaginal color Doppler and power Doppler sonography: report of two cases

Craniofacial osteomas are benign tumors of the skull base, often involving the paranasal sinuses. The frontal sinus is the most common site of involvement, followed by the ethmoid, maxillary, and sphenoid sinuses, respectively. The growth rate is very slow, and it may take many years for osteomas to become clinically apparent. The origin of these tumors has been ascribed to embryologic tissue maldevelopment, trauma, or infection. The tumors are hard and lobulated with an ivory-like appearance, often mixed with a coarse granular component. The bone is compact or cancellous, with vascular or connective tissue components. The complications of osteoma growth are obstruction of sinus ostia, extension into adjacent bones and the intracranial cavity, and displacement of anatomic structures. Management of uncomplicated sinus osteomas is controversial, since surgery involves serious potential risks. When surgery is performed, these tumors can be successfully managed via endoscopic, open, or combined techniques. This article reviews the clinical findings, diagnostic studies, and treatment of 16 patients with paranasal osteomas. The indications for surgical intervention are discussed.     

The effect of removable partial denture framework design on gingival inflammation: a clinical model

A clinical trial using the experimental gingivitis model developed for periodontal clinical research was performed to evaluate the effect of a removable partial denture mandibular major connector design on the surrounding gingival tissues. A comparison of the state of health of adjacent gingival tissues was made between the linguoplate (control) and cingulum bar (test) major connectors. Clinical parameters were recorded in a single-blind crossover experimental gingivitis trial. Subjects were brought to a level of optimal gingival health and then randomly assigned to use one framework design while refraining from any oral hygiene. Measurements were made at 7-day intervals for 21 days. The subjects were returned to optimal oral health and repeated the experimental period with the alternate design. Results showed a greater increase in mean gingival inflammation with the control than with the test removable partial denture, suggesting that the cingulum bar has fewer detrimental effects on gingival tissues than the linguoplate major connector. Results of this study suggest that the experimental gingivitis model can be a useful and valid system for studying the potential effects of a removable partial denture design on surrounding oral tissues.     

Faecal chymotrypsin in small for gestational age infants: effects of nucleotides and breast feeding

The effect of diet on pancreatic exocrine function, measured by faecal chymotrypsin activity (FCA), was studied longitudinally in three groups of small for gestational age (SGA) infants in the first six months of life. The three groups comprised breastfed infants (group B), those randomly allocated to receive a standard infant formula (group S), or the same formula supplemented with nucleotides (group N). The three groups did not differ in their birthweight or gestational age. Nucleotide supplementation of infant formula improves catchup growth in SGA infants but whether this is due to effects on the gastrointestinal mucosa or the exocrine pancreas is not known. There were no differences in FCA at study entry but by one month group B had significantly lower values than the other groups, and this was maintained at 2, 4, and 6 months. Groups N and S did not differ significantly at any time point. Nucleotide supplementation of infant formula does not influence pancreatic exocrine function and its effect on growth is unlikely, therefore, to be mediated through the pancreas. This study shows that breast feeding is associated with lower FCA which may be related to the lower protein content of human milk. Reliable interpretation of FCA in young infants requires information about their diet.     

Infant feeding and weaning practices in some semi-arid rural areas of Rajasthan

The paper contains information on infant feeding and weaning practices in the rural communities of a semi-arid district of Rajasthan. The findings have been drawn from a recent survey of 328 rural mothers. The rural women of this area are found to believe in old deep seated beliefs and customs, which in turn deprive their infants from advantages of colostrum (77% discarded colostrum) and nutritionally rich supplements, which otherwise should be supplemented to them at any cost in order to keep them healthy. The practices of prolonged breast feeding and delayed supplementation to infants are rampant in this area. Mean age at weaning (27.1 months) again not only affects the health status of mothers and their children but also leads to the undernutrition among both. The findings of the study necessitate to evolve an exhaustive educative programme dealing with various aspects of infant feeding and weaning practices, keeping in view their traditions, so that the useful practices can be encouraged and harmful ones be prohibited.     

Calcium waves in retinal glial cells

Calcium signals were recorded from glial cells in acutely isolated rat retina to determine whether Ca2+ waves occur in glial cells of intact central nervous system tissue. Chemical (adenosine triphosphate), electrical, and mechanical stimulation of astrocytes initiated increases in the intracellular concentration of Ca2+ that propagated at approximately 23 micrometers per second through astrocytes and Müller cells as intercellular waves. The Ca2+ waves persisted in the absence of extracellular Ca2+ but were largely abolished by thapsigargin and intracellular heparin, indicating that Ca2+ was released from intracellular stores. The waves did not evoke changes in cell membrane potential but traveled synchronously in astrocytes and Müller cells, suggesting a functional linkage between these two types of glial cells. Such glial Ca2+ waves may constitute an extraneuronal signaling pathway in the central nervous system.