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R Navarro

Publications and source records attributed to R Navarro.

At least 37 records · Page 2Linked to original sources
PubMed2001

Worsening of hepatic dysfunction as a consequence of repeated hydroxyethylstarch infusions.

BACKGROUND/AIMS: Due to its apparent safety and low cost, hydroxyethylstarch (HES) is increasingly used as a volume expander. The aim of this retrospective study was to highlight the risk of hepatic dysfunction after iterative HES infusions. METHODS: Between April 1996 and April 1998, nine patients were referred for worsening of their clinical condition after repeated HES infusions. Six patients had previous chronic liver disease, cirrhosis in four cases. All patients underwent a liver biopsy. RESULTS: All post-HES liver biopsies showed diffuse microvacuolization of Kupffer cells, which was associated with focal hepatocyte vacuolization in seven cases. The vacuoles contained periodic acid Schiff positive material at their margins and were lysosomal by electron microscopy. The clinical symptoms of hepatic disease, although difficult to interpret in cirrhotic patients, worsened after HES infusions. Portal hypertension was noted in three non-cirrhotic patients. Serum alkaline phosphatase and gammaglutamyl transferase activities were increased when compared with previous values. Eight patients died, six of them within 1-4 weeks of hepatic failure or septic shock. In the only living patient, symptoms improved after HES withdrawal. CONCLUSIONS: Repeated administration of HES could favour severe portal hypertension, liver failure and sepsis, particularly in the setting of chronic liver disease. The basis of these adverse effects is the lysosomal storage of HES in Kupffer cells and hepatocytes.

Aged↗
PubMed2001

[Recurrence of finger tendon giant cell tumors after excision through a "shark teeth" approach. Report of 25 cases].

Local recurrences after excision of a giant cell tumor of the tendon sheath are classically related to incomplete excision. We have review a special group of circumferential tumors excised through a huge approach. Twenty-six circumferential tumors were excised between 1985 and 1998, through a special incision described by the senior author. It is composed of four triangular flaps drawn around the finger, one dorsal, one palmar (both proximally based) and two lateral (distally based). Six presented already with a recurrence of previous operations (mean 2.5 interventions). Some anatomical neighboring structure was "invaded" in all except one case. However the approach allows for a macroscopically satisfactory excision. Twenty-five patients were reviewed by an independent observator after a mean follow-up of six years. Six patients (24%) presented a recurrence after a mean postoperative delay of 17 months. Among them five have been already operated (83%) and five had multiple tumors. Satisfactory excision does not prevent recurrence and two types of distinct tumors exist. Recent immunohistological studies give support to this view and such examination is recommended.

Adult↗
PubMed2001

[Percutaneous needle aponeurotomy. Complications and results].

Recently French rheumatologists have repopularized fasciotomy using a percutaneous needle technique. This blind approach has been claimed to be plagued by numerous complications. We reviewed the charts of 211 patients treated consecutively on 261 hands and 311 fingers to assess the rate of postoperative complications. The first 100 patients were evaluated with a mean follow up of 3.2 years to assess the rate of recurrences and extension of the disease. In the whole group the mean age was 65 years and delay between onset and treatment was six years. Rupture of the cords were performed only in the palm in 165 cases, in the palm and finger in 111 and purely at digital level in 35. Complications were scarce without infection or tendon injury but one digital nerve was found injured during the second procedure. Postoperative gain was prominent at metacarpophalangeal joint level (79% versus 65% at interphalangeal level). Reoperation rate was 24%. In the group controlled at 3.2 years follow up, recurrence rate was 58% and disease "activity" 69%. Fifty nine hands need further surgery. The ideal indication for this simple and reliable technique is an elderly patient with a bowing cord and a predominant MP contracture.

Adult↗
PubMed2001

Acquired haemophilia in the elderly is a severe disease: report of five new cases.

Acquired haemophilia is a rare but life-threatening bleeding disease that can be observed in males or females at various ages. In the present study, we report on five cases of acquired factor (F) VIII inhibitors diagnosed in the elderly population over a period of 5 years between 1995 and 1999 in our hospital. The median age of the patients at the time of diagnosis was 76.2 years (66-92 years). In all cases, the diagnosis was suggested by mild to severe bleeding with no previous bleeding history. While the absence of associated conditions is frequently reported especially among the elderly, in our series an underlying disease was found in four out of the five cases: kidney tumour (two cases) and autoimmune disease (two cases). The bleeding was controlled in four patients using porcine FVIII (two cases) or recombinant FVIIa (two cases). The inhibitors were completely resolved in two patients (kidney tumour, GoodPasture syndrome) by treatment of the underlying disease. However, three patients died as direct or indirect consequence of having an inhibitor. Our series confirms and extends previous data reporting the complexity and severity of this disorder. Because bleeding is often severe, a prompt and correct diagnosis is required to provide adequate therapeutic options that take the advanced age of the patients into account.

Aged↗
PubMed2001

Toe transfer in congenital hand malformations.

Fifty-eight patients with congenital hand abnormalities underwent 65 toe-to-hand transfers. Symbrachydactyly (51 cases) was the most frequent indication. Forty-seven second toe-to-hand transfers were performed in 44 patients. The mean follow-up time was 5.2 years. Two failures occurred in cases in which only one artery was anastomosed; no failures were noted when more than one artery fed the transfer. Two patients with a single second-toe transfer presented with lateral instability of the transferred metatarsophalangeal joint. The mean active range of motion was 38 degrees, with a mean extension lag of 25 degrees. The mean two-point discrimination was 5 mm. Forty-one patients used the transferred toe well, when performing activities of daily living and playing games. Toe-to-hand transfer, prior to the establishment of the grip pattern, facilitates integration of the transfer.

Child, Preschool↗
PubMed2001

Microsurgical reconstruction of the hypoplastic thumb, type IIIB.

If a classically hypoplastic thumb, type IIIA, presenting with a first carpometacarpal joint, is amenable to reconstruction, a type IIIB case without the basal joint, is classically treated by pollicization. The authors concur with this opinion, but found two circumstances in which reconstruction is an option in a type IIIB thumb, either when an adolescent asks for improvement of an unstable but utilized thumb, or when a parent definitely refuses pollicization. In such cases, a free, vascularized metatarsophalangeal joint is the first step of the reconstruction, followed by classic non-microsurgical steps. The authors reviewed five cases, with a mean follow-up of 7.8 years. Hypoplasia of the reconstructed thumb, and a limited pinch, allow this option only with restricted indications.

Hand Deformities, Congenital↗
PubMed2001

Comparing laser ray tracing, the spatially resolved refractometer, and the Hartmann-Shack sensor to measure the ocular wave aberration.

PURPOSE: To compare quantitatively three techniques to measure the optical aberrations of the human eye: laser ray tracing (LRT), the Hartmann-Shack wavefront sensor (H-S), and the spatially resolved refractometer (SRR). LRT and H-S are objective imaging techniques, whereas SRR is psychophysical. METHODS: Wave aberrations were measured in two normal subjects with all three techniques implemented in two different laboratories. RESULTS: We compared the experimental variability of the results obtained with each technique with the overall variability across the three methods. For the two subjects measured (RMS wavefront error 0.5 microm and 0.9 microm, respectively), we found a close agreement; the average standard deviation of the Zernike coefficients within a given method was 0.07 microm, whereas the average global standard deviation across techniques was 0.09 microm, which is only slightly higher. CONCLUSIONS: There is a close match between the Zernike coefficients obtained by LRT, H-S, and SRR. Thus, all three techniques provide similar information concerning wave aberration when applied to normal human eyes. However, the methods are operationally different, and each has advantages and disadvantages depending on the particular application.

Adult↗
PubMed2001

Metacarpal synostosis: a simple classification and a new treatment technique.

The current classification of metacarpal synostosis is based on the extent of the synostosis. The authors propose a new classification that takes into account the shape of the metacarpal bones, the curvature of the epiphysis, and the discrepancy in length between the two bones. This classification provides better guidelines for the correction of all components of the deformity. The classification is based on the authors' observations of and experience with 36 cases of metacarpal synostosis; 13 of the deformities were surgically corrected. The I-shaped deformity, whether with distinct (type d) or fused (type f) metacarpophalangeal joints, does not require surgical correction. The U-shaped deformity has parallel epiphysis and does not require surgery unless the two metacarpals are asymmetrical in length (type a) or tightly fused (type t); in these cases, simple lengthening or widening of the space with a bone graft is sufficient. Y-shaped synostosis should be separated whether the branches are symmetrical or asymmetrical, the latter having one branch shorter than the other. Because the epiphyses are already divergent, simple separation does not effectively correct Y-shaped synostosis. The authors propose an osteotomy to isolate a trapezoidal segment of bone from the bifurcation. The isolated bone segment is then reversed in the proximal-distal direction to provide a "plateau" upon which the two distal metacarpals can be realigned. Two cases of Ys (symmetrical) synostosis were successfully treated with this technique; one case of Ya (asymmetrical) synostosis also required distraction lengthening of the shorter metacarpal to achieve an excellent result. One of the most difficult types of metacarpal synostosis to treat is k-shaped synostosis, observed only between the fourth and fifth metacarpals; in this type, the head of the short fifth metacarpal abuts the metaphysis of the fourth. Osteotomy and distraction lengthening provide predictable results for correction of this deformity. The authors suggest that k-shaped synostosis might represent a late evolution of untreated Ua synostosis.

Child, Preschool↗
PubMed2001

Ocular aberrations before and after myopic corneal refractive surgery: LASIK-induced changes measured with laser ray tracing.

PURPOSE: To determine objectively the changes in the ocular aberrations (3rd order and above) induced by myopic LASIK refractive surgery and its impact on image quality. METHODS: The ocular aberrations of 22 normal myopic eyes (preoperative refraction ranged from -13 to -2 D) were measured before (2.9 +/- 4.3 weeks) and after (7.7 +/- 3.2 weeks) LASIK refractive surgery using a laser ray tracing technique. A set of laser pencils is sequentially delivered onto the eye through different pupil locations. For each ray, the corresponding retinal image is collected on a CCD camera. The displacement of the image centroid with respect to a reference provides direct information of the ocular aberrations. Root-mean-square (RMS) wavefront error was taken as image quality metric. RESULTS: RMS wavefront error increased significantly in all eyes but two after surgery. On average, LASIK induced a significant (P = 0.0003) 1.9-fold increase in the RMS error for a 6.5-mm pupil. The main contribution was due to the increase (fourfold, P < 0.0001) of spherical aberration. The increase in the RMS for a 3-mm pupil (1.7-fold) was also significant (P = 0.02). The modulation transfer (computed for 6.5-mm pupil) decreased on average by a factor of 2 for middle-high spatial frequencies. CONCLUSIONS: (1) Laser ray tracing is a well-suited, robust, and reliable technique for the evaluation of the change of ocular aberrations with refractive surgery. (2) Refractive surgery induces important amounts of 3rd and higher order aberrations. The largest increase occurs for spherical aberration. Decentration of the ablation pattern seems to generate 3rd order aberrations. (3) This result is important for the design of customized ablation algorithms, which should cancel existing preoperative aberrations while avoiding the generation of new aberrations.

Adult↗
PubMed2001

[Progressive bone lengthening of the hand in congenital malformations. 41 cases].

PURPOSE OF THE STUDY: We retrospectively reviewed the experience of two Hand Units with progressive bone distraction lengthening, collecting 41 cases of hand skeleton lengthening for congenital malformations. MATERIAL AND METHODS: The Ilizarov callostasis method was used in 31 cases and in 10 cases bone union was reestablished at a second stage with an iliac graft (2 cases), vascularized metacarpal bone graft (one case), and vascularized (one case) or nonvascularized (3 cases) toe epiphysis. In the last three cases of index lengthening, the distal part was translocated to the tip of the third, deepening at the same stage the first web. The most frequently treated malformation was symbrachydactyly (22 cases). RESULTS: Mean lengthening was 2.3 cm (0.9 to 3.5) with a mean treatment duration of 3.8 months (1.5 - 8.2). The "lengthening index" was 0.59. There was a significant difference between phalanx and metacarpal lengthening, but the amount of lengthening or treatment duration were not affected by technique (Ilizarov vs bone grafting) or age. The complication rate was 32%. There were two complete failures, one extensor tendon tear, 3 pin tract infections (one requiring interruption of the lengthening), 2 cases of relevant pain, 2 delayed unions, 2 angulations and 1 callus fracture, 1 metacarpophalangeal dislocation and 1 joint stiffness. DISCUSSION: Despite advances in micorsurgical toe transfer, there are still indications for bone lengthening in congenital malformations. The apparent simplicity of the technique can mask a certain number of complications, emphasizing the need for surgical experience. Progressive bone lengthening in congenital deformity has the advantage of preserving sensitivity and avoiding bone resorption. Callostasis does not increase the duration of treatment compared to bone graft.

Adolescent↗
PubMed2001

The treatment of gastroesophageal reflux disease with proton-pump inhibitors and its implications on managed care--clinical overview of gastroesophageal reflux disease. Roundtable discussion.

The importance of gastroesophageal reflux disease (GERD) to managed health care systems cannot be overestimated. It contributes significantly to the use of health care resources, including doctor's services, medication consumption, and diagnostic testing. A roundtable meeting of 13 managed care experts was convened January 23, 2001 in Dallas, to discuss the implications of GERD on the managed care system. The following proceedings are published in five sections. In the first part, Jeffrey Danzig, MD, a gastroenterologist, provides the clinical foundation for the discussion, based on the existing literature and his personal practice.

Anti-Ulcer Agents↗
PubMed2001

Uterine prolapse in 2 dromedary camels.

Two cases of uterine prolapse in dromedary camels in a herd with concomitant cases of white muscle disease are described. Serum selenium and glutathione peroxidase in whole blood were investigated in both patients and showed statistical difference compared with a control group. Results suggest that selenium deficiency could promote uterine prolapse in dromedary camels.

Animals↗
PubMed2000

Molecular batteries: ferrocenylsilylation of dendrons, dendritic cores, and dendrimers: new convergent and divergent routes to ferrocenyl dendrimers with stable redox activity

The ferrocenylsilylation of the phenol triallyl dendron 2, of the phenol nonaallyl dendron 4, and of the 9-, 27-, 81-, and 243-allyl dendrimers 7-10 (monitored by the disappearance of the signals of the olefinic protons in 1H NMR spectra) has been achieved using ferrocenyldimethylsilane 1 and Karstedt's catalyst in diethyl ether at 40 degrees C, yielding the corresponding ferrocenyl dendrons and dendrimers. An alternative convergent synthesis of the nonaferrocenyl dendron 5 was carried out by reaction of the triferrocenyl dendron 2 with a protected triododendron followed by deprotection. Reaction of the nonaferrocenyl dendron 5 with hexakis(bromomethyl)benzene gave the 54-ferrocenyl dendron 6. All the ferrocenyl dendron and dendrimers produce a chemically and electrochemically reversible ferrocenyl oxidation wave at seemingly the same potential. Stable platinum electrodes modified with the high ferrocenyl dendrimers were fabricated. The soluble orange-red ferrocenyl dendrimers can also be oxidized in CH2Cl2 by [NO][PF6] to the insoluble deep blue polyferrocenium dendrimers. For instance, the 243-ferrocenium dendrimer has been characterized by its Mossbauer spectrum, which is of the same type as that of ferrocenium itself. The ferrocenium dendrimers can be reduced without any decomposition back to the ferrocenyl dendrimer, indicating that these multielectronic redoxstable dendrimers behave as molecular batteries.

Journal Article↗
PubMed2000

Vibrational analysis and spectra of orotic acid.

The IR and Raman spectra of polycrystalline anhydrous orotic acid and its N1, N3, and O12 trideuterated isotopomer are recorded in the 4000-40 cm(-1) spectral interval as part of a series of vibrational analyses of nucleosides, nucleotides, and related compounds carried out in our laboratory. The frequencies of the fundamental transitions and the potential energy distributions of the 39 normal modes of orotic acid and its isotopomer are calculated by an ab initio density functional theory Becke3P86/6-311G** treatment. Assignments of the vibrational modes are proposed that consider the results of these calculations and the observed spectra. The results of the ab initio treatment are related to crystallographic and spectral data, and they are compared with previous assignments for similar molecules.

Deuterium↗