Disodium cromoglycate protects dystrophin-deficient muscle fibers from leakiness

In dystrophin-deficient fibers of mdx mice and in Duchenne dystrophy, the lack of dystrophin leads to sarcolemma breakdown and muscle degeneration. We verified that cromolyn, a mast-cell stabilizer agent, stabilized dystrophic muscle fibers using Evans blue dye as a marker of sarcolemma leakiness. Mdx mice (n=8; 14 days of age) received daily intraperitoneal injections of cromolyn (50 mg/kg body weight) for 15 days. Untreated mdx mice (n=8) were injected with saline. Cryostat cross-sections of the sternomastoid, tibialis anterior, and diaphragm muscles were stained with hematoxylin and eosin. Cromolyn dramatically reduced Evans blue dye-positive fibers in all muscles (P<0.05; Student's t-test) and led to a significant increase in the percentage of fibers with peripheral nuclei. This study supports the protective effects of cromolyn in dystrophic muscles and further indicates its action against muscle fiber leakiness in muscles that are differently affected by the lack of dystrophin.     

Role of interstitial apatite plaque in the pathogenesis of the common calcium oxalate stone

By using intraoperative papillary biopsy material from kidneys of idiopathic calcium oxalate, intestinal bypass for obesity, brushite, cystine, and distal renal tubular acidosis stone formers during percutaneous nephrolithotomy, we have determined that idiopathic calcium oxalate stone formers appear to be the special case, although the most commonly encountered one, in which stones form external to the kidney and by processes that do not involve the epithelial compartments. It is in this one group of patients that we find not only abundant interstitial plaque, but also strong evidence that the plaque is essential to stone formation. The initial site of plaque formation is always in the papillary tip, and must be in the basement membrane of the thin loop of Henle. With time, plaque spreads throughout the papilla tip to the urothelium, which under conditions we do not understand is denuded and thereby exposes the apatite deposits to the urine. It is on this exposed apatite that a stone forms as an overgrowth, first of amorphous apatite and then layers of calcium oxalate. This process generates an attached stone fixed to the side of a papilla, allowing the ever-changing urine to dictate stone growth and composition.     

New insights into the pathogenesis of idiopathic hypercalciuria

Idiopathic hypercalciuria (IH) is the most common metabolic abnormality in patients with calcium kidney stones. It is characterized by normocalcemia, absence of diseases that cause increased urine calcium, and calcium excretion that is greater than 250 mg/d in women and 300 mg/d in men. Subjects with IH have a generalized increase in calcium turnover, which includes increased gut calcium absorption, decreased renal calcium reabsorption, and a tendency to lose calcium from bone. Despite the increase in intestinal calcium absorption, a negative calcium balance is seen commonly in balance studies, especially on a low-calcium diet. The mediator of decreased renal calcium reabsorption is not clear; it is not associated with either an increase in filtered load of calcium or altered parathyroid hormone levels. There is an increased incidence of hypercalciuria in first-degree relatives of those with IH, but IH appears to be a complex polygenic trait with a large contribution from diet to expression of increased calcium excretion. Increased tissue vitamin D response may be responsible for the manifestations of IH in at least some patients.     

Ureteric stent card register - a 5-year retrospective analysis

INTRODUCTION

Ureteric stenting is a common urological procedure. Forgotten stents have a well-documented morbidity and mortality. Therefore, we asked the question, is a stent register an important factor in reducing the number of lost or overdue stents?

PATIENTS AND METHODS

We conducted a retrospective review of 203 patients who had ureteric stents inserted in the operating theatre, for the 5-year period 1 December 1998 to 1 December 2003. We analysed all stent cards, patient notes and theatre logs; where no record of stent removal was found, we contacted the patient, their GP or their local hospital.

RESULTS

A total of 191 patients were identified from the stent card register. An additional 12 patients were found from the theatre logs, but with no record in the stent card register. Of the 203 patients, 8 had bilateral stents. The most common indication for stenting was stone disease. Of the 203 patients, 11 had overdue stents and 51 had no record of the stents ever being removed. The 51 presumed ‘forgotten’ stents were traced, and it was found that 42 patients had had their stents removed by other hospitals, and 9 patients died with stents in situ, but before they were due for removal.

CONCLUSIONS

Our current stent card tracking system is ineffective, because it was infrequently reviewed. However, despite overdue and ‘forgotten’ stents which were removed by other hospitals, no patients came to any real harm and we had no lost stents. Our stent register system did not appear to play any role in terms of preventing stent loss, and it seems likely that there are other more effective safeguards in place to prevent this from happening. However, if a stent register was required at all, a computerised system would be preferable. Alternatively, patients could share some of the responsibility of stent tracking with their clinicians.     

Kt/V underestimates the hemodialysis dose in women and small men

Current guidelines suggest a minimum Kt/V of 1.2 for three weekly hemodialysis sessions; however, using V as a normalizing factor has been questioned. Parameters such as weight(0.67) (W(0.67)) and body surface area (BSA) that reflect the metabolic rate may be preferable. To determine this, we studied 328 hemodialysis patients (221 male) with a target Kt/V of 1.2. Using this relationship and the individual's Watson Volume, we calculated the Kt, Kt/BSA, and Kt/W(0.67) equivalent to the target and measured the effects of body size and gender on these parameters for each patient. The target corresponded to a range of equivalent Kt/BSA and Kt/W(0.67) each significantly higher in males than females and in larger than smaller males. V/BSA and V/W(0.67), the conversion factors of Kt/V to Kt/BSA and Kt/W(0.67) respectively, were significantly greater in males than females and heavier than lighter men. Our study shows that if Kt/BSA and Kt/W(0.67) reflect the true required dose, prescribing a target Kt/V of 1.2 would underestimate this in females and in small males. Further work is required to develop clinical outcome-based adequacy targets.     

Antileishmanial and antifungal activity of plants used in traditional medicine in Brazil

The antileishmanial and antifungal activity of 24 methanol extracts from 20 plants, all of them used in the Brazilian traditional medicine for the treatment of several infectious and inflammatory disorders, were evaluated against promastigotes forms of two species of Leishmania (L. amazonensis and L. chagasi) and two yeasts (Candida albicans and Cryptococcus neoformans). Among the 20 tested methanolic extracts, those of Vernonia polyanthes was the most active against L. amazonensis (IC(50) of 4 microg/ml), those of Ocimum gratissimum exhibited the best activity against L. chagasi (IC(50) of 71 microg/ml). Concerning antifungical activity, Schinus terebintifolius, O. gratissimum, Cajanus cajan, and Piper aduncum extracts were the most active against C. albicans (MIC of 1.25 mg/ml) whereas Bixa orellana, O. gratissimum and Syzygium cumini exhibited the best activity against C. neoformans (MIC of 0.078 mg/ml).     

Outcome assessment of bracing in adolescent idiopathic scoliosis by the use of the SRS-22 questionnaire

The SRS-22 questionnaire is specifically designed for the assessment of quality of life in spinal deformity patients. This study is the first to use it to assess the quality of life of adolescent idiopathic scoliosis patients under brace treatment and compares the results with an observational group matched by age and curve magnitude. Forty-six patients were enrolled into each group. Overall, it was found that patients under observation had a significantly better quality of life than braced patients. Specifically, the domains for function/activity and self-image were most affected. This effect was most apparent in those with a curve magnitude of under 20 degrees . The scores did not improve significantly with the duration of brace wear, suggesting little adaptation. This study has implications for treatment, and more attention will need to be given to those with mild but progressive curves to help improve patients' understanding of their treatment and hence their compliance and satisfaction.     

Strauch's technique for epigastric free flaps in rats revisited: a simple and effective method to increase patency rates

Described by Strauch and Murray in 1967, the rodent epigastric free flap remains a versatile tool for microsurgery research and training. We report herein three sequential phases of our quest to improve efficiency and effectiveness of the original technique, making it more accessible to more microsurgeons. Ninety-six allotransplants were performed. Surgical technique, complication rates, clinical findings, and histopathologic correlation of each phase are reported. In phase I, two experienced microsurgeons employed the original technique and succeeded in 77% of the procedures. In phase II, two junior microsurgeons achieved a patency rate of 16.6% using the same technique, as opposed to 100% in phase III, utilizing the not-yet-described simplified flow-thru technique. Although patency rate using the original method varies from 9 to 78% (according to other reports), this technical modification can increase even the less experienced microsurgeons' success rates, perpetuating the use of Strauch's epigastric flap in experimental microsurgery.