The ulnar tunnel: a rare disposition of its contents

The ulnar tunnel is located at the proximal part of the hand radial to the pisiform bone and to the proximal part of the carpal tunnel. Inside it lie the ulnar nerve and artery. Compression of the ulnar nerve in this tunnel is often reported. Cysts, occupational trauma, fractures and muscle variations are among the main causes (Schjelderup, 1964; Kleinert & Hayes, 1971). Damage to the ulnar nerve and artery during the endoscopic decompression of the carpal tunnel has been reported recently (Agee et al. 1992; Nath et al. 1993; De Smets & Fabry, 1995). The structures within the ulnar tunnel are closely related to the medial part of the flexor retinaculum, in particular the ulnar artery which is located lateral to the ulnar nerve. During a study of this region we found a rare disposition of the contents of this tunnel. We believe that knowledge of this variation is important for the surgical anatomy of this region.     

Relation Between Cellular Repolarization Characteristics and Critical Mass for Human Ventricular Fibrillation

INTRODUCTION: The critical mass for human ventricular fibrillation (VF) and its electrical determinants are unclear. The goal of this study was to evaluate the relationship between repolarization characteristics and critical mass for VF in diseased human cardiac tissues. METHODS AND RESULTS: Eight native hearts from transplant recipients were studied. The right ventricle was immediately excised, then perfused (n = 6) or superfused (n = 2) with Tyrode's solution at 36 degrees C. The action potential duration (APD) restitution curve was determined by an S1-S2 method. Programmed stimulation and burst pacing were used to induce VF. In 3 of 8 tissues, 10 microM cromakalim, an ATP-sensitive potassium channel opener, was added to the perfusate and the stimulation protocol repeated. Results show that, at baseline, VF did not occur either spontaneously or during rewarming, and it could not be induced by aggressive electrical stimulation in any tissue. The mean APD at 90% depolarization (APD90) at a cycle length of 600 msec was 227+/-49 msec, and the mean slope of the APD restitution curve was 0.22+/-0.08. Among the six tissues perfused, five were not treated with any antiarrhythmic agent. The weight of these five heart samples averaged 111+/-23 g (range 85 to 138). However, after cromakalim infusion, sustained VF (> 30 min in duration) was consistently induced. As compared with baseline in the same tissues, cromakalim shortened the APD90 from 243+/-32 msec to 55+/-18 msec (P < 0.001) and increased the maximum slope of the APD restitution curve from 0.24+/-0.11 to 1.43+/-0.10 (P < 0.01). CONCLUSION: At baseline, the critical mass for VF in diseased human hearts in vitro is > 111 g. However, the critical mass for VF can vary, as it can be reduced by shortening APD and increasing the slope of the APD restitution curve.     

UMBILICAL CORD CORTISOL AND PROLACTIN LEVELS IN PRETERM INFANTS

ABSTRACT. The influence of labor and route of delivery upon the umbilical cord serum levels of cortisol and prolactin in ninety-nine preterm infants not exposed prenatally to corticosteroids was studied. Vaginally born infants (group A) presented a higher mean cord cortisol concentration than those delivered by cesarean section (group B); mean prolactin values, however, were not different between both groups. Although there was no difference in cortisol and prolactin levels between infants delivered by cesarean section after spontaneous onset of labor (group B-I) and those without labor (group B-II), the mean cortisol concentration was significantly higher in group A than in group B-I. The mean prolactin levels did not differ among all the studied groups. It is concluded that there is no association between presence of labor or route of delivery and cord seum levels of prolactin, there is no association between spontaneous preterm labor and cord cortisol values and there is an association between vaginal delivery and high cord cortisol levels in preterm infants. It is suggested that the increase in serum cortisol levels does not precede the initiation of preterm parturition but it is secondary to the stress caused by vaginal delivery.     

MELANOCYTE RESERVOIR IN VITILIGO

Background. Dopa-negative, inactive melanocytes, present in the middle portion of the hair follicle, but also in hair bulbs, have been reported as a source of pigment cells, when repopulation of epidermal melanocytes occurs. A melanocyte reservoir in these anatomical sites has been suggested. Our objective was to investigate the ability of the lower third of the hair follicle (hair bulb) to repigment achromic skin in vitiligo. Methods. Scalp hair bulbs were transplanted within leukodermic areas in 10 patients with vitiligo. Results. Repigmentation around the grafts was suitable for evaluation in four cases. Dopa-positive (+) cells were seen in the epidermal basal cell layer of the repigmented areas. Conclusions. Although these findings were observed only in a few patients, they suggest that melanocytes from the implanted lower third portion of the hair follicle (hair bulb) act as a reservoir in this anatomic location and are able to migrate and repigment achromic areas in vitiligo.     

LEPROMATOUS AND TUBERCULOID LEPROSY: CLINICAL PRESENTATION AND CYTOKINE RESPONSES

Objective. This study analyzes the major clinical characteristics of patients with active leprosy in relation to the in vitro immune response to the T- lymphocyte activator anti-CD3. Methods. Thirty-eight patients with an established diagnosis of leprosy were classified according to the Ridley and Jopling table. Peripheral blood mononuclear cells from both lepromatous leprosy (LL) and tuberculoid leprosy (TL) patients and healthy controls were used to evaluate lymphocyte proliferation; immunoenzymatic assays were used to evaluate cytokine production (IL-I, IL-2, IL-4, IL-6, IL-10, IFN-gamma). Results. Peripheral blood mononuclear cells from both LL and TL patients displayed blastogenic responses to anti- CD3. The cytokines IL-1β, IL-6, IL-10, and IFN-γ were detected in culture supernatants. Endogenous production of IL-1ß was significantly higher in cell cultures from patients with the lepromatous form of the disease compared to those with tuberculoid leprosy. Production of IL-6 in response to anti CD3 was observed in a significantly higher proportion of LL than TL patients (P = 0.0025). Gamma-interferon production did not differ between TL and LL, but a direct correlation was observed between time of multidrug treatment and IFN production in vitro (P = 0.016). Interleukin-10 was detected in culture supernatants of lymphocytes activated by anti-CD3 from both patient groups, but not from healthy controls. Conclusions. The findings of this study suggest that patients with the two distinct forms of leprosy are capable of responding to a polyclonal T-lymphocyte stimulus such as anti-CD3 and provide evidence suggestive of alterations in the immune responses mediated by cytokines that may contribute to the spectrum of disease and response to treatment.     

Radiofrequency Catheter Ablation of an Incessant Supraventricular Tachycardia Initiated by a Hisian Parasystole

The coexistence of a pamsystolic focus, tachycardia dependent right bundle branch aberrancy, and an AV accessory pathway is reported here. This condition was present in a 40-year-old man, which led to an incessant AV reciprocating tachycardia. Further electrophysiological study revealed that the parasystolic focus was located somewhere in the His bundle; endocardial mapping disclosed a right posterior accessory pathway. Radiofrequency current was delivered at the atrial level of the right posterolateral AV groove and successfully ablated the accessory pathway, leading to a dramatic improvement in cardiac function. In conclusion, the recognition of the electrophysiological mechanism of incessant Supraventricular tachycardia was of crucial importance for the therapy decision. A definitive intervention using radiofrequency catheter ablation should be considered early and not postponed in patients with tachycardia-induced cardiomyopathy.     

Congenital absence of the testis in human fetuses and in cryptorchid patients

BACKGROUND: The aim of the present study is to make a comparative study in human fetuses and in patients with cryptorchidism, analyzing the incidence of a number anomalies of the testes for both populations. METHODS: We studied 326 testes from 163 human fetuses ranging in age from 10 to 35 weeks postconception (WPC) and 133 testes from 101 cryptorchid patients aged from 1 to 15 years old (mean, 6.4 years). The Fisher's exact test was used for comparison. RESULTS: Among 326 fetal testes, 224 (68.7%) were abdominal, 45 (13.8%) were inguinal and 55 (16.8%) were scrotal. In one fetus at 23 WPC, both testes (0.6%) were absent. Of the 133 cryptorchid testes, 17 (12.78%) were abdominal, 92 (69.1%) were inguinal and 24 (18%) were high scrotal. Of the 17 abdominal testes, three (17.6%) were atrophic and two were vanished (11.7%). Of the 92 inguinal testes, one (1.08%) was vanished. Twenty-eight (21%) of the cryptorchid testes were impalpable and among these, 17 were located in the abdomen (60.7%) and 11 (38.2%) in the inguinal region (internal ring). CONCLUSIONS: Testicular agenesis is a very rare anomaly, both in fetuses and patients with cryptorchidism.     

Neutralization of the activity of a Fasciola hepatica cathepsin L proteinase by anti-cathepsin L antibodies

Fasciola hepatica secretes a cathepsin L proteinase that is suggested to play an in vivo role in immunoprotection since the enzyme can cleave host immunoglobulin. In the present report, rabbit anti-cathepsin L IgG was shown to bind to the cathepsin L enzyme and inhibit its ability to cleave IgG molecules. Cathepsin L can prevent the antibody-mediated attachment of eosinophils to newly excysted juveniles in in vitro assays; however, if anti-cathepsin L IgG are mixed with the cathepsin L prior to the addition of the enzyme to the assay, eosinophils attach to the newly excysted juveniles. Thus it is possible to prepare antibodies that can bind and disrupt the biological activity of the F. hepatica cathepsin L.     

Down to the Wire: Tricuspid Stenosis in the Setting of Multiple Pacing Leads

Tricuspid stenosis in the setting of endocardial pacing leads is a rare entity, attributed to infection or lead malposition. We report the case of a 37‐year‐old man without these risk factors, who presented with new onset severe tricuspid stenosis in the setting of multiple chronic pacing leads. (PACE 2010; e49–e52)