Biomedical subjects

J A Robles

Publications and source records attributed to J A Robles.

6 recordsLinked to original sources

PubMed2005

Reliability of zone IV in the deep inferior epigastric perforator flap: a single center's experience with 74 cases.

From March 2000 to June 2002, 74 deep inferior epigastric perforator (DIEP) flaps were performed in 73 female patients for oncological post-mastectomy breast reconstruction in Chang Gung Memorial Hospital. The mean age was 44.2 years and mean body weight was 56.6 kg. Twenty-five breast reconstructions were immediate and 49 were delayed. The average size of the flap was 30.1x12.0 cm and the mean number of perforators was 2.2. The average weight of the harvested flap was 595 g and 85.6% (mean: 509 g) of the flap was used for shaping the new breast mound. Zone IV was not discarded, except in one case. Total flap failure and donor site morbidity was not encountered. Only one flap was revised due to venous congestion (1.4%) and successfully salvaged. Partial flap loss occurred in two patients (2.7%). Fat necrosis was detected in 10 cases (13.5%) and sizes ranged from 2x2 to 4x5 cm. The numbers of perforators and the percentage of the used flap weight/total flap weight were not related to the complications. The free DIEP flap and inclusion of zone IV is a reliable and valuable method of breast reconstruction and provides superior aesthetic outcomes.

Abdomen↗

PubMed2005

Mycotic pseudoaneurysms after liver transplantation.

The most frequent etiology of visceral artery aneurysms is arteriosclerosis, but vascular manipulation during hepatic transplantation may also cause a mycotic pseudoaneurysm. Treatment with embolization, stents or percutaneous thrombin injection have been recommended but surgical revascularization is indicated when interventional techniques fail. A 43-year-old man with hepatitis C virus cirrhosis who underwent orthotopic liver transplantation from a cadaveric donor was treated with cyclosporine, mycophenolate, and steroids and was discharged from hospital at 35 days. Two months later he was readmitted with a febrile syndrome. Abdominal computed tomography showed necrosis of hepatic segments IV, V, and VI. Magnetic resonance imaging and angiography revealed partial thrombosis of the hepatic artery and stenosis of the portal anastomosis secondary to an aneurysm of the hepatic artery. A few hours after the radiological diagnosis, the patient suffered a bout of upper gastrointestinal bleeding and shock. Emergency surgery revealed a mycotic pseudoaneurysm of the common hepatic artery, which had ruptured into the bile tract with hemobilia. The liver graft was removed because of severe necrosis of the right liver. The patient died awaiting a new liver transplantation.

Adult↗

PubMed2000

Stimulus frequency affects c-fos expression in the rat visual system.

We have characterised the c-fos expression patterns in various centers of the visual pathway of adult rats monocularly stimulated either by continuous or flickering light at different frequencies. Results show different immunocytochemical patterns in all centers studied, the geniculate lateral complex (LGC), superior colliculus (SC) and primary visual cortex (Oc1), depending on the physical characteristics of the stimulus (blinking frequency and light wavelength). After stimulation of the left eye, the ipsilateral pathway presents a substantial density of immunoresponsive cells, which is greater than expected with respect to the number of fibers that project ipsilaterally from the retina to the LGC and the superficial layers of the SC. A surprisingly high positive immunoresponsiveness is obtained in all cases with coherent light stimulation in the red spectrum (634 nm).

Animals↗

PubMed2000

Preservation of a digital osteotendinous structure with an omental flap.

Taking into account the angiogenic properties of the omentum to revascularize ischemic tissues, this experimental, longitudinal, prospective, double-blind study in rabbits was designed to revascularize and preserve the mobility of a digital osteotendinous structure surgically devascularized in advance and to compare such omental angiogenic ability with that of the muscle and the panniculus carnosus. Thirty New Zealand rabbits were used. Three toes from the hind feet were surgically amputated from each rabbit. The skin was removed, exposing the bones, tendons, ligaments, and joints, to form what we termed the osteotendinous structure. Through a median laparotomy, the first part of each rabbit's own osteotendinous structure was placed inside the panniculus carnosus (group I), the second under the rectus abdominis muscle (group II), and the third was wrapped in a pediculate omental flap (group III). Three weeks later, each structure was assessed clinically for mobility and fibrosis and microscopically for fibrosis, newly formed vessels, viability, and tissue regeneration. Clinically, the group I structures showed a greater amount of fibrosis. The structures in groups II and III showed minimal fibrosis in all but four cases, which showed moderate fibrosis. Differences in joint mobility were assessed with the Kruskal-Wallis test. There was a statistically significant difference in mobility for the structures from group III, which was higher, followed by those from groups II and I. The exception was the proximal interphalangeal joints in groups II and III, for which the differences had no statistical significance. Microscopically, fibrosis and tissue necrosis were intense in the structures in group I, moderate in the group II structures, and mild in the group III structures. Conversely, vessel neoformation and tissue regeneration were intense in the structures in group III, moderate in group II, and were nil in group I. This study confirms with statistical significance that, in the rabbit, the omentum has a higher ability to revascularize degloved tissues than do the muscle and the panniculus carnosus, thus preserving a higher joint and tendon mobility. Consequently, it is suggested that a free omental flap be used in the treatment of ring avulsion injuries that lead to degloving of the digits.

Abdominal Muscles↗

PubMed1997

Usefulness of cryohemolysis test in the diagnosis of hereditary spherocytosis.

The clinical suspicion of hereditary spherocytosis (HS) must be confirmed at the clinical laboratory. The osmotic fragility test (OFT) and the autohemolysis test (AHT) are the worldwide accepted assays to establish a definite diagnosis of HS; however, they have some disadvantages. We describe herein our experience with the cryohemolysis test (CHT) as a tool to confirm the HS diagnosis. We included four groups of subjects, namely, patients with clinical HS, patients with mechanical heart valve prosthesis, malignant hematological diseases and healthy blood donors. CHT was carried out in all the groups, while OFT and AHT only in the HS patients and healthy individuals. OFT and AHT were performed according to previously described techniques. CHT was performed using red blood cells incubated in a hypertonic solution, preheated for 10 min and then transferred to an ice bath for an additional 10 min. The resulting cryohemolysis was determined measuring the free hemoglobin in the sample. There were no differences among the groups in terms of general characteristics. All HS suspicious patients had a positive OFT and AHT. CHT was positive in all patients from the HS group but in none of the subjects from the control groups (p < 0.001). We found that CHT is a faster and easier-to-perform assay compared with OFT and AHT. Moreover, using CHT, the zone between normal and abnormal results is wider than OFT or AHT. We propose 0.7 to 11% hemolysis as reference values for CHT.

Adult↗

PubMed1997

Diagnostic value of the copper/zinc ratio in digestive cancer: a case control study.

The aim of this study was to assess the accuracy of the copper/zinc ratio (Cu/Zn ratio) in the evaluation of a large group of patients with digestive cancer compared to gender and age-matched control subjects. A total of 282 patients was studied and separated into three groups: group I (n = 75), patients with digestive cancer, group II (n = 112), patients with benign digestive disease, and group III (n = 95), healthy subjects. Serum levels of copper and zinc were measured by atomic absorption spectrophotometry. The results showed that the serum levels of copper (mg/dL) in patients with digestive cancer (91.6 +/- 27.3, p < 0.05) were significantly higher than in patients with benign digestive disease (75.8 +/- 19.8) or healthy subjects (54.4 +/- 8.9) and the serum levels of zinc (mg/dl) were significantly lower (68.7 +/- 21.9, p < 0.05) compared to benign digestive disease patients (80.1 +/- 18.7) or healthy subjects (100 +/- 11.4 mg/dl). The Cu/Zn ratio was also significantly higher in patients with digestive cancer (1.45 +/- .58, p < 0.05) than those with benign digestive disease (0.95 +/- 0.28) or healthy subjects (0.55 +/- 0.13). Considering a cutoff value of 0.87, the sensitivity of the copper/zinc ratio was 82.2%, with a specificity of 65.7%, a positive predictive value of 45.8% and a negative predictive value of 91.3%. In conclusion, Cu/Zn ratio was found to be considerably higher in patients with digestive cancer compared to age- and gender-matched controls, with a sensitivity of 82.2% that might be useful in the evaluation of suspected malignancy.

Adult↗