The overlooked, retained double J stent

A series of 4 patients with long overlooked, retained ureteral stents is presented to illustrate the variable, unpredictable, and at times, hazardous course of such patients. These cases are cited to re-emphasize the need for careful documentation, observation, and follow-up of patients in whom stents are placed.     

Involvement of alkylating agents in schistosome-associated bladder cancer: the possible basic mechanisms of induction.

Carcinoma of the urinary bladder is a common malignancy in many tropical and subtropical countries. There is a well documented sequela of chronic urinary schistosomal infection and bladder cancer associated with schistosomiasis is a major cause of morbidity and mortality in the endemic areas. Experimental bladder cancer can be induced in schistosome-infected animals. Multiple factors have been suggested as causative agents in schistosome-associated bladder carcinogenesis and the N-nitroso compounds appear to be of particular importance. These agents have long been suspected to play a major role in the aetiology of a variety of human cancers. A model for the induction of bladder cancer associated with schistosomiasis is proposed which takes into account the interrelationships between different factors resulting from the infection, especially the role of alkylating agents that can contribute to the induction of this neoplasm.     

Mechanisms of resistance to Leishmania aethiopica. I. Interferon-gamma in combination with a cytokine (not tumor necrosis factor-alpha) is required, but cannot act alone in the inhibition of intracellular forms of L. aethiopica in THP1 cells.

Following exposure to promastigotes of various Leishmania species, mononuclear cells from non-exposed as well as potentially exposed individuals produced a cytokine response which inhibited intracellular forms of Leishmania aethiopica in a permissive monocytic cell line (THP1). Interferon-gamma (IFN-gamma), was one of the cytokines responsible for this anti-leishmanial effect. IFN-gamma was necessary for inhibition but could not act on its own inhibiting L. aethiopica. Tumor necrosis factor-alpha seemed not to be involved in the anti-L. aethiopica effect. The observed effects were in the absence of endotoxin. The results suggest that the mechanisms of killing of L. aethiopica in human cells may differ from those responsible for inhibition of other Leishmania parasites (such as Leishmania major) in mouse macrophages. Furthermore, that potentially relevant responses to Leishmania antigens may exist in normal individuals.     

Soleus H-reflex measures in patients with focal and generalized dystonia.

OBJECTIVE: The purpose of this study was to examine neurophysiological characteristics of dystonia patients using electromyographic soleus H-reflex methods. METHODS: Thirty normal healthy individuals were compared to 27 patients with focal (cervical) or generalized dystonia. Three H-reflex assessment methods were included: the ratio of maximum H-reflex to direct muscle potential (H/M ratio); vibration inhibition (H(v)/H(c) ratio); and H-reflex recovery curves (HRRC). RESULTS: Average H/M ratios between groups were not statistically significant. The average H(v)/H(c) ratio for the generalized dystonia group was significantly greater than the focal dystonia and normal groups. Average values of the HRRC showed the generalized dystonia group had significantly greater disinhibition than the focal dystonia and control groups during the early inhibition phase. The HRRC for the focal dystonia group was greater than normal and more similar to the generalized dystonia group during the late phases of the recovery curve. The average value of the localized late facilitation phase for the focal dystonia group was significantly greater than the control group and less than the generalized dystonia group. No differences were observed between groups for the average localized late inhibition phase of the recovery curve. CONCLUSIONS: Soleus H-reflex measures identified neurophysiologic differences between generalized dystonia, cervical dystonia and normal conditions. SIGNIFICANCE: This methodology enables analysis of the underlying characteristics of dystonic pathologies using soleus H-reflex methods rather than upper extremity H-reflex techniques.     

Complications in infants undergoing surgery for congenital cataract in the first 12 weeks of life: is early surgery better?

PURPOSE: To determine if there is an association between the timing of surgical intervention for congenital cataract within the first 12 weeks of life and the prevalence of postoperative complications. METHODS: We performed a retrospective review of records from 1990 to 2000 of infants who underwent surgery for congenital cataract within the first 12 weeks of life. Eighty eyes in 55 children were involved with a minimum follow up of 6 months. Bilateral cataracts were present in 25 and monocular cataracts in 30 infants. A limbal approach lensectomy-vitrectomy was performed in all infants. Children with aphakia were rehabilitated with contact lens or glasses. Operative and postoperative complications-including glaucoma, nystagmus, strabismus, retinal detachment, and posterior capsule opacification/secondary membranes-were recorded. Ocular and systemic associations were noted. Statistical analysis was carried out with classification and regression trees (CART). RESULTS: The mean age at the time of surgery was 31.5 +/- 23.3 days (median, 26.5; range, 2 to 84). Mean follow up from the time of surgery was 2.85 +/-1.9 years (median, 2; range, 0.5 to 8). Persistent fetal vasculature (persistent hyperplastic primary vitreous) was present in 14 eyes. One infant with bilateral persistent fetal vasculature had bilateral retinal dysplasia and was excluded from the analysis. Glaucoma developed in 12 infants (22%); nystagmus was present in 18 infants (33%); strabismus developed in 28 infants (52%); and secondary membranes developed in 7 eyes (13%). CART analysis suggests that glaucoma is more prevalent in infants when the surgery was performed between 13.5 and 43 days of life (CART = 0.370); nystagmus when surgery is performed between 48 and 84 days of life (CART = 0.500); strabismus when surgery is performed between 55.5 and 84 days of life (CART = 0.600); and secondary membranes when surgery is performed between 26.5 and 40 days of life (CART = 0.4). CONCLUSIONS: Our data suggest that the first 2 weeks of life comprise the most favorable time for decreasing postoperative complications resulting from surgical intervention for infants presenting with cataracts within the first 12 weeks of life.     

Right superficial femoral artery to superior vena cava graft using a polytetrafluroethylene graft: a new technique in a complicated dialysis access patient.

Sir, The expansion of haemodialysis includes older patients withcomorbidities, poor quality vessels, unsuitable for transplantationor peritoneal dialysis. Vascular access complications accountfor 20% of hospital admissions [1]. With exhausted sites inupper extremities, unusual sites for arteriovenous grafts formationare used [2]. The