Hirschsprung's Disease Complicating Pregnancy

The first case of uncorrected Hitschsprung's disease complicating pregnancy is reported. The congenital aganglionic megacolon was confirmed by tissue biopsy. Following the completion of her pregnancy, the patient had definitive surgical correction of her malady. A brief discussion of bowel obstruction in pregnancy is included.     

UNILATERAL TESTICULAR INJURY FROM EXTERNAL TRAUMA: EVALUATION OF SEMEN QUALITY AND ENDOCRINE PARAMETERS

Purpose

Because few studies have described the impact of unilateral testicular trauma on fertility parameters, we review the experience at the Ben Taub General Hospital during a 16-year period. Semen and endocrine profiles were analyzed to evaluate the influence on the outcomes of orchiectomy versus testicular salvage.

Materials and Methods

From 1979 to 1995, 67 patients were identified who sustained unilateral testicular trauma. Of these patients 12 were located and 10 agreed to be evaluated. Injuries included gunshot wounds, stab wounds and blunt trauma, and treatment consisted of unilateral orchiectomy or testicular repair. The study protocol comprised a history and physical examination, routine semen analysis, determination of semen and serum antisperm antibody titers (Immunobead* assay) and a modified gonadotropin stimulation test. Results were compared with a group of semen donors with proved fertility.Biorad, Seattle, Washington.

Results

In the 7 patients who underwent unilateral orchiectomy mean sperm density was normal but significantly decreased compared with that of the fertile controls (81.6 versus 132.6 × 10⁶/ml., p = 0.04). Sperm motility was not significantly affected. Baseline follicle-stimulating hormone (FSH) and luteinizing hormone (LH), and post-stimulation LH were significantly increased in this group compared with controls (p <0.01). In the group that underwent testicular repair sperm density, motility, and baseline and post-stimulation FSH and LH levels were not significantly different from controls. In all patients in both groups testosterone levels and contralateral testicular size were normal. Only 1 patient in the repair group had an elevated serum and semen antisperm titer.

Conclusions

While the testicular salvage group had no significant seminal or endocrine abnormality, the orchiectomy group had a significant decrease in sperm density and elevation of baseline FSH and LH. These preliminary data suggest that testicular salvage is more protective of overall testicular function than orchiectomy.     

Bile secretion by the rat liver during synchronized regeneration

Simultaneous coexistence of differentiated, proliferating and re-differentiated hepatocytes occurs during normal liver regeneration (LR). The aim of the present work was to study the time course of the capacity of the liver to form bile during synchronized LR. Following two-thirds partial hepatectomy (PH) in rats, i.v. administration of the ribonucleotide reductase reversible inhibitor hydroxyurea (HU) was used to transiently block liver cells at G1/S boundary. Experiments were performed at 0 and 4 hours, and 1, 3 or 7 days after releasing HU-induced inhibition. Bile acid pool size was determined by collecting bile samples over 24 hours. Initial (first hour) bile flow and bile acid output were increased early on during synchronized LR as compared with the values found in non-hepatectomized control animals. These values were thereafter (1 day) reduced, but increased again at 3 days after halting HU infusion. The time course of bile acid depletion and changes in bile flow were very similar in control and synchronized LR, except that in the latter a more important early reduction in bile flow and bile acid output was found. Shortly after PH, part of the bile acid pool was lost, but this was quickly restored, soon (1 day) reaching a net bile acid pool size very similar to that found in control rats. The highest pool size relative to liver weight was found on day 1, when bile acid output and bile flow reached their lowest values. Additional experiments were performed using in situ perfused regenerating rat livers in which stepwise infusion of taurocholate (TC) was carried out. PH alone modified neither the bile acid-independent (BAIF) nor the bile acid-dependent fraction of bile flow (BADF). However, in normal LR, the BAIF decreased on day 1 and recovered at 7 days, while in synchronized LR it remained depressed up to 7 days. The BADF was only reduced during the early phase of normal LR and did not change significantly in synchronized LR. The maximal secretion rate (SRmax) for TC, as expressed per gram of remaining liver tissue, was not affected immediately after PH, but a marked reduction was observed on day 1 in both normal and synchronized LR. Afterwards, SRmax was quickly restored in both synchronized LR and, although in a slower way, normal LR. These results suggest that synchronization of LR involves changes in the time required to the recovery of specific liver functions such as bile formation.     

Left ventricular mass in hypertensive patients with mild‐to‐moderate reduction of renal function

Aim: Left ventricular hypertrophy (LVH) is an independent predictor of cardiovascular (CV) morbidity and mortality. The aim of the present study was to evaluate the relationship between LV mass and mild‐to‐moderate renal dysfunction in a group of non‐diabetic hypertensives, free of CV diseases, participating in the Renal Dysfunction in Hypertension (REDHY) study. Methods: Patients with diabetes, a body mass index (BMI) of more than 35 kg/m², secondary hypertension, CV diseases and a glomerular filtration rate (GFR) of less than 30 mL/min per 1.73 m² were excluded. The final sample included 455 patients, who underwent echocardiographic examination and ambulatory blood pressure monitoring. Results: There was a significant trend for a stepwise increase in LV mass, indexed by both body surface area (LVMI) and height elevated to 2.7 (LVMH^2.7), with the declining renal function, that remained statistically significant after correction for potential confounders. The prevalence of LVH, defined either as LVMI of 125 g/m² or more or as LVMH^2.7 of 51 g/m^2.7 or more, was higher in subjects with lower values of GFR than in those with normal renal function (P < 0.001 in both cases). The multiple regression analysis confirmed that the inverse association between GFR and LVM was independent of confounding factors. Conclusion: The present study confirms the high prevalence of LVH in patients with mild or moderate renal dysfunction. In the patients studied (all with a GFR of 30 mL/min per 1.73 m²), the association between LVM and GFR was independent of potential confounders, including 24 h blood pressure load. Taking into account the negative prognostic impact of LVH, further studies focusing on a deeper comprehension of the mechanisms underlying the development of LVH in chronic kidney disease patients are needed.     

Assessment of RNA amplification by multiplex RT‐PCR and IgM detection by indirect and capture ELISAs for the diagnosis of measles and rubella

Sanz JC, Mosquera M, Ramos B, Ramírez R, de Ory F, Echevarria JE. Assessment of RNA amplification by multiplex RT‐PCR and IgM detection by indirect and capture ELISAs for the diagnosis of measles and rubella. APMIS 2010; 118: 203–9. The aim of the study was to compare RNA amplification using multiplex RT‐PCR and IgM detection by means of indirect and capture ELISAs for the diagnosis of measles and rubella. A total of 229 cases of maculopapular rash with serum and throat swab samples were included. Specific serological IgM to measles and rubella was determined by Enzygnost^® (Siemens) and Platelia^TM (Bio‐Rad). Both viruses were researched using multiplex RT‐PCR performed on throat samples. Criteria for inclusion of measles or rubella cases were a positive RT‐PCR result for one virus and negative for the other; and/or a positive IgM result for one virus by both ELISAs and negative RT‐PCR for the other virus. A total of 74 cases were classified as measles and 54 as rubella. In measles, sensitivity and specificity were 93.2% and 100% for RT‐PCR, 97.3% and 98.1% for Enzygnost^®, and 90.5% and 95.5% for Platelia^TM. For rubella, these values were 42.6% and 100% for RT‐PCR, 100% and 97.1% for Enzygnost^®, and 94.4% and 98.3% for Platelia^TM. Enzygnost^® and Platelia^TM are useful techniques for detecting IgM against measles and rubella. RNA amplification by RT‐PCR was both sensitive and specific for the diagnosis of measles; however, for rubella, the sensitivity of this technique must be improved.     

CHRONIC MENINGOCOCCEMIA IN AN IMMUNOCOMPETENT GIRL

A 13-year-old healthy girl consulted with a 4-week history of recurrent fever (39–40°C) and erythematous macules and plaques on the distal parts of her legs and forearms, and the palms and soles, A migrating arthritis developed on the left ankle and, later, on the knees, elbows, wrists, and hand joints. General symptoms included anorexia, malaise, and weight loss. Physical examination revealed several erythematous macules, plaques, and nodules, 1–3 cm in diameter, located on the anterior and posterior aspects of the legs, soles, forearms, dorsum of the hands, and palms (Fig. 1), Some lesions showed very small petechiae and vesicles in the center. The nodules in acral locations were painful. A hemogram displayed mild anemia (hemoglobin 11.3 g/dL) and leukocytosis (11,500 WBc/mm³). The erythrocyte sedi-mentation rate was 63 mm in 1 hour. Serum biochemistry, protein and protein fractions, and fractions of immunoglobu-lins were within normal limits. Urinalysis showed microhe-maturia and a few leukocytes. Two serial blood cultures were taken during the first two febrile peaks after admission, but both were negative. A third one (1 week after admission) was positive for group B Neisseria meningitidis. This bacterium was also recovered from pharyngeal samples, but was not isolated in the culture of cerebrospinal fluid. Antibiotic therapy was established with intravenous cephtriaxone, 100 mg/kg/day for 10 days, with dramatic im-provement of the fever and arthritis within 3 days. The cu-taneous lesions disappeared within 1 week. Some of the components of complement proteins (C3, C4, and C5) were measured to rule out any deficiency, but they were normal. A normal value of CH50 supported the adequate presence of all of the components of the mem-brane attack complex (C6 to C9) in the serum. Several relatives of the patient were found to be oropha-ryngeal carriers of group B Neisseria meningitidis. They were treated successfully with rifampin (20 mg/kg/day for 2 days).     

Opposite Effects of Myocardial Stretch and Verapamil on the Complexity of the Ventricular Fibrillatory Pattern: An Experimental Study

CHORRO, F.J., et al. : Opposite Effects of Myocardial Stretch And Verapamil on The Complexity of The Ventricular Fibrillatory Pattern: An Experimental Study. An experimental model is used to analyze the effects of ventricular stretching and verapamil on the activation patterns during VF. Ten Langendorff‐perfused rabbit hearts were used to record VF activity with an epicardial multiple electrode before, during, and after stretching with an intraventricular balloon, under both control conditions and during verapamil (Vp) infusion (0.4–0.8 μmol). The analyzed parameters were dominant frequency (FrD) spectral analysis, the median (MN) of the VF intervals, and the type of activation maps during VF (I = one wavelet without block lines, II = two simultaneous wavelets with block lines, III = three or more wavelets with block lines). Stretch accelerates VF (FrD: 22.8 ± 6.4 vs 15.2 ± 1.0 Hz, P < 0.01; MN: 48 ± 13 vs 68 ± 6 ms, P < 0.01 ). On fitting the FrD time changes to an exponential model after applying and suppressing stretch, the time constants (stretch: 101.2 ± 19.6 s; stretch suppression: 97.8 ± 33.2 s ) do not differ significantly. Stretching induces a significant variation in the complexity of the VF activation maps with type III increments and type I and II decrements (control: I = 17.5%, II = 50.5%, III = 32%; stretch: I = 7%, II = 36.5%, III = 56.5%, P < 0.001 ). Vp accelerates VF (FrD: 20.9 ± 1.9 Hz, P < 0.001 vs control; MN: 50 ± 5 ms, P < 0.001 vs control ) and diminishes activation maps complexity (I = 25.5%, II = 60.5%, III = 14%, P < 0.001 vs control ). On applying stretch during Vp perfusion, the fibrillatory process is not accelerated to any greater degree. However, type I and II map decrements and type III increments are recorded, though reaching percentages similar to control (I = 16.5%, II = 53%, III = 30.5%, NS vs control ). The following conclusions were found: (1) myocardial stretching accelerates VF and increases the complexity of the VF activation pattern; (2) time changes in the FrD of VF during and upon suppressing stretch fit an exponential model with similar time constants; and (3) although stretching and verapamil accelerate the VF process, they exert opposite effects upon the complexity of the fibrillatory pattern.     

Muscarinic Effects on Action Potential Duration and its Rate Dependence in Canine Purkinje Fibers

Studies of the autonomic influence on action potential duration (APD) in the ventricles show direct effects of muscarinic stimulation on epicardial, but not endocardial, APD and conflicting results regarding direct vagal effects on the conduction system. In canine Purkinje fibers, we analyzed the action of the M₂ agonist oxotremorine (OXO, 0.1μM) on APD and on its cycle length (CL) dependence. Fibers were impaled with glass microalectrodes and superfused with Tyrode s solution. APD₉₀ was measured after 3 minutes of drive at CL between 0.3 and 5 seconds. The best fit for the APD/CL relationship at steady state was a hyperbole: APD = APD_max*CL/(CL+CL₅₀), where APD_max (APD at infinite CL) is a rate independent measure of APD, and CL₅₀ (CL at which 50% APD_max is reached) is an index of the rate dependence of APD. In five fibers, OXO reduced APD at all CL (P < 0.05), APD_max was also reduced to 377 ± 41 ms from 447 ± 34 ms (P < 0.05), while CL₅₀ was unchanged (405 ± 46 ms from 437 ± 28 ms). No effects of OXO on APD and APD_max were seen in two fibers obtained from dogs pretreated with pertussis toxin (PTX). In conclusion, stimulation of M₂ receptors in intact, and not PTX treated, Purkinje fibers affects APD but not its CL dependence. This may reflect the activation of a rate independent, background current through a GTP binding protein-linked pathway, such as, I_K.ACH These data differ from those obtained in endocardial and epicardial muscle, stressing the regional differences in vagal modulation of ventricular electrophysiological properties.     

The Atria: From Morphology to Function

Functional Anatomy of the Atria . The fact that some atrial and ventricular disorders (e.g., atrial fibrillation and heart failure) have a structural basis and cause atrial myocardial remodeling has led to increasing attention being paid to the atrial chambers. Furthermore, the rapid development of mapping and ablative procedures as a means of diagnosing and treating supraventricular arrhythmias has generated considerable interest in atrial gross anatomy, histology and ultrastructure. The aim of this article is to provide a comprehensive overview of the structure of the left and right atria (at macroscopic, histological and ultrastructural level) in relation to their function. In addition to analyzing normal atria, we also discuss functional anatomy in the case of atrial fibrillation and heart failure. (J Cardiovasc Electrophysiol, Vol. 22, pp. 223‐235, February 2011)