PubMed Health⌕ Search

Biomedical subjects

C Alfonso

Publications and source records attributed to C Alfonso.

At least 37 records · Page 2Linked to original sources
PubMed1990

Nucleases in the autolysis of filamentous fungi.

RNase and DNase activities were studied in seven fungi of the subdivisions Ascomycotina, Zygomycotina and Basidiomycotina during their autolysis, and extracellular and intracellular RNase and DNase were found. RNase specific activity reached higher levels than DNase specific activity in the culture liquid and mycelial extract, except in Aspergillus nidulans. Generally maximal RNase specific activities were observed at the onset of autolysis in the culture liquid. In the mycelial extract an increase in this activity with the incubation time was observed, except in A. nidulans and Coriolus versicolor. The highest values of DNase specific activities were found at the third day of autolysis in A. nidulans culture liquid and at the thirtieth day of autolysis in Schizophyllum commune mycelial extract. A possible relationship between the culture liquid pH during the autolysis of the studied fungi and the levels of DNase specific activity was observed.

Ascomycota↗
PubMed1990

Cephalosporin C acylase in the autolysis of filamentous fungi.

Cephalosporin C acylase activity was studied using fluorescamine determination of free--NH2 groups produced in the deacylation of cephalosporin C by the enzyme. Fourteen fungi from different genera were studied and low extracellular cephalosporin C acylase activity was found in the genera Aspergillus, Fusarium and Penicillium. Forty one fungi of these genera were checked but not all presented acylase activity. The enzyme was generally found to be an extracellular enzyme and during the process of autolysis its activity increased with incubation time and with increasing pH of the medium. In no case was beta-lactamase activity detected. Penicillium rugulosum and Penicillium griseofulvum were identified as good cephalosporin C acylase producers. Deacetyl esterase activity was also detected in these fungi.

Amidohydrolases↗
PubMed1989

Penicillin amidohydrolases in fungal autolysis.

The production of penicillin G and penicillin V amidohydrolases or acylases (E.C.3.5.1.11) was studied during the autolysis of filamentous fungi in a mineral medium, and in the same medium with phenoxyacetic acid as inducer. In all the studied fungi, enzymes showing penicillin G and penicillin V amidohydrolase activities were found. Generally, an increase of these activities during fungal autolysis was observed. The presence of phenoxyacetic acid in the medium did not increase these activities. The activities found in the culture fluids were generally higher than that found in the mycelial extracts. Under these conditions, beta-lactamases (penicillinases) were not found. The fungi Alternaria alternata, Fusarium culmorum, Penicillium oxalicum, and the species Penicillium 222 were chosen to study penicillin G and penicillin V acylases. The enzymes were precipitated with tannic acid from the culture fluid of their autolyzed cultures. Some kinetic constants of these activities were determined.

Amidohydrolases↗
PubMedDate not supplied

Disseminated intravascular coagulation during total hip replacement.

Disseminated intravascular coagulation (DIC) is an extremely serious hemorrhagic disorder and one that is potentially lethal. DIC is more frequently observed as a complication of obstetric pathologies, diffused neoplasms, bacterial sepsis, blood transfusions, traumas and adipose embolias. The literature reports very few cases occurring after total hip replacement, two of which the cause of death. In all of the cases described one or boh prosthetic components are cemented. The authors report a case observed after total hip replacement in a patient submitted one year previously to contralateral hip replacement. Severe hypotension, bradychardia and profuse bleeding of the wound and from the drainages one hour after suturing constituted the initial symptom. Recognition of the clinical findings, after exclusion of a iatrogenic lesion, and subsequent treatment in intensive therapy allowed us to save the patient. The syndrome must be suspected and immediately diagnosed when profuse bleeding that cannot be related to vascular lesion is observed immediately postsurgery after cemented or hybrid hip replacement. Confirmation through hematological tests and timely treatment in a specialized center are indispensable requirements to save the life of the patient.

Aged↗
PubMedDate not supplied

Anterior surgery for the treatment of soft cervical disc herniation.

The authors present the results obtained in a series of 57 cases of soft cervical disc herniation submitted to anterior surgery. The cases included 52 radiculopathies and 5 myeloradiculopathies. Among the radiculopathies, 20 cases were treated by discectomy without magnification, and interbody fusion, and 32 by radical microdiscectomy, completed with interbody fusion in 19 cases and without fusion in 13. The 5 cases of myeloradiculopathy were all treated by microdiscectomy, with fusion in 2 cases and without fusion in 3. The results of treatment of the radiculopathies were evaluated as excellent or good in 80% of the cases treated by "macro" technique, and in 84% of those treated with "micro" technique; in the latter cases, more rapid and complete regression of pain, were always observed probably due to the more radical neurological compression obtained. The 5 cases of myeloradiculopathy obtained excellent results, with evident sensory and motor recovery. Long-term results for cases treated with or without fusion did not differ; the complications observed in the entire series may all be related to use of interbody grafting. The authors conclude that the method of choice in the surgical treatment of soft cervical herniation, with radicular or myeloradicular compression, is radical anterior microdiscectomy without interbody fusion.

Bone Transplantation↗
PubMedDate not supplied

Degenerative spondylolisthesis: lumbar stenosis and instability.

Degenerative spondylolisthesis may manifest itself with different clinical pictures depending on the phase of the spondylotic disease. Based on pathophysiological criteria 24 patients affected with degenerative spondylolisthesis were divided into three groups: group I: those with spondylotic instability; group II: those with lumbar stenosis and current or potential segmental instability; group III: those with lumbar stenosis and naturally stabilized spondylolisthesis. Group I was treated by posterolateral fusion; group II by laminectomy, removal of the medial portion of the facets and posterolateral fusion; group III by laminectomy and removal of the medial portion of the facets. Long-term results were positive in 100% of the cases in group I, 90% in group II and 83% in group III, with no statistically significant differences between groups, because of the limited series of cases. The authors conclude that surgery for the treatment of degenerative spondylolisthesis must be based on age, symptoms, and the phase of the disease, and that when these indications suited to the clinical-radiographic picture are taken into account, good results may be obtained with different operations.

Adult↗
PubMedDate not supplied

Complications in the surgical treatment of lumbar stenosis.

The authors analyze the complications which may occur in the surgical treatment of lumbar stenosis. They report 4 cases of cauda equina syndrome and 8 dural tears in 96 patients aged from 21 to 81 years submitted to multiple bilateral laminectomy. Based on a review of the patients some considerations on surgery for the treatment of lumbar stenosis are discussed. The advanced age of the patients, hypertension, diabetes, vasculopathies in general, severe neurological deficit dating back some time contraindicate surgery. When surgery is indicated a correct preoperative evaluation by MRI from T12 to the sacrum is required to determine the extent of the laminectomy and a safe and accurate intra- and postoperative bleeding control is mandatory. Dural laceration may be repaired by a thoracolumbar fascia patch.

Age Factors↗
PubMedDate not supplied

Lumbosciatic pain and coagulopathies.

Three cases of nerve compression causing lumbosciatic pain and/or cruralgia due to hematoma secondary to coagulopathies of varying etiology are described. The cases involved a multiple nerve root syndrome of the cauda equina due to extradural hematoma in coagulopathy resulting from the administration of dicumarol drugs, a neuropathy of the crural nerve caused by hematoma of the iliopsoas muscle in hemophilia B, and a neuropathy of the sciatic nerve caused by hematoma in the gluteus and thigh in coagulopathy resulting from the administration of dicumarol drugs. In all three of the cases the clinical picture resembled that of lumbar disc herniation, but a careful evaluation of each patient's history, objective picture, and laboratory and radiological testing allowed us to make a correct diagnosis. Medical therapy is based on the correction of the coagulopathy by means of suitable drugs or hemoderivates. Surgical treatment is reserved for the most severe cases.

Acute Disease↗
PubMedDate not supplied

Extruded cervical disc herniation: treatment with anterior microdiscectomy.

Nine cases of extruded cervical disc herniation (7 with radiculopathy, 2 with acute myeloradiculopathy) were treated by radical anterior microdiscectomy, with opening of the posterior longitudinal ligament, removal of the extruded peridural disc material, bilateral resection of the posterior part of the uncovertebral joints; in 6 cases surgery was completed with Smith-Robinson intersomatic fusion. In all of the cases symptoms rapidly regressed, with considerable neurological recovery. There were no major complications in any of the cases, and 2-5 years after surgery results were evaluated as excellent in 7 cases and good in 2. The use of the operating microscope allows for removal of extruded disc herniations under magnification, in a bloodless surgical field and with no manipulation of the nervous structures. Because of these features, this method is preferred to traditional posterior surgery and anterior surgery without magnification.

Adult↗
PubMedDate not supplied

Lateral retrovascular approach to the upper cervical spine.

The authors describe the surgical anatomy of lateral approach to the upper cervical spine. The approach is retrovascular retropharyngeal extraoral allowing for anterolateral exposure of the upper cervical column, and it may be enlarged posteriorly on the homolateral posterior hemiarch of C1 and C2, and/or inferiorly on the lower cervical column. Absolute indications to this approach are anterolateral fusion with transarticular screws C1-C2 and excision of skeletal neoplasms adjacent to the vertebral artery. For other indications such as the treatment of anterior neoplasms and spinal cord decompression it is preferable to use pre-vascular extraoral approach or transoral approach.

Adolescent↗
PubMedDate not supplied

Failed back syndrome: a study on 95 patients submitted to reintervention after lumbar nerve root decompression for the treatment of spondylotic lesions.

The persistence of lumbar and nerve root pain after nerve root decompression surgery may be attributed to one of five causes; 1) progression of the spondylotic disease in the presence of peridural fibrosis; 2) recurrence of disc herniation or new hernia; 3) stenosis of the spinal or nerve root canal; 4) arachnoiditis; 5) vertebral instability. In most patients with peridural fibrosis and worsening of spondylotic lesions regression of nerve root symptoms was obtained after several months of conservative treatment, which continues to constitute essential treatment for most patients with recurrence of lumbar symptoms. The authors report the results obtained with the surgical treatment of 95 patients performed between 1981 and 1991 and divided into the categories listed above. Of these patients, 70 were submitted to further decompression surgery while 25 were submitted to posterolateral vertebral fusion. Reintervention obtained useful results in 83% of the cases where there had been recurrence of disc herniation; nerve root release obtained positive results in 100% of the cases where there was stenosis. Results obtained after wide decompression were poor in all of the cases with arachnoiditis; in these patients conservative treatment with T.E.N.S. can obtain a fair amount of control over pain. Positive results were obtained in 84% of the 25 patients submitted to posterolateral fusion for the treatment of vertebral instability, with fusion obtained in 96% of the cases. Surgical treatment is indicated for psychotic, neurotic patients or those with insurance-related motivations only when the organic cause of the symptoms is clearly evident.

Adolescent↗
PubMedDate not supplied

Differential diagnosis of low back pain.

Low back pain is a symptom common to many vertebral and extravertebral affections. The origin of low back pain mostly derives from a pathology localized in the spine, as in the case of degenerative lesions, neoplastic lesions, infections, fractures, metabolic diseases such as osteoporosis, or more rarely, rheumatological diseases. The causes of extravertebral low back pain may be renal, pancreatic, gastrointestinal, or of the female genital apparatus. The authors present a series of clinical aspects which must always be taken into consideration in order to avoid errors in the diagnosis and evaluation of a patient with low back pain.

Diagnosis, Differential↗
PubMedDate not supplied

Posterolateral spinal fusion: a study of 123 cases with a long-term follow-up.

A total of 123 patients submitted to posterolateral fusion according to the Wiltse method were followed-up after 2-10 years (mean 6 years and 2 months). The series included: isthmic spondylolisthesis: 80; degenerative spondylolisthesis: 18; failed back syndrome: 25. Good morphological fusion of the arthrodesis evaluated by conventional radiology and CT, was obtained in 87% of the entire series, while in 89% of the cases excellent or good clinical results were obtained according to the Friberg evaluation scale. Extent of the fusion to 1 or 2 intervertebral segments, or association of laminectomy did not influence the results. Clinical and radiographic results were maintained stable in time: in only 3 cases did we observe clinical deterioration due to degeneration of the segment located above the fusion 3-7 years after surgery. The only important complications observed were one cauda equina syndrome due to peridural hematoma after laminectomy-fusion, and one iliocaval venous thrombosis. The results of the series studied and the data reported in the literature show that posterolateral fusion is a method capable of providing a high percentage of good clinical and radiographic results, and it may be favorably compared with methods of interbody fusion and of pedicular fixation, compared to which it has the advantage of involving a minor number of complications. Anterior interbody fusion is however indicated for stabilization of the reduction of severe spondylolisthesis in the adolescent. Fusion with pedicular osteosynthesis is indicated for the treatment of macroscopic instability and in fusions which are extended to more than two intervertebral segments.

Adolescent↗