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Biomedical subjects

A Ferro

Publications and source records attributed to A Ferro.

At least 37 records · Page 2Linked to original sources

[Biomechanical aspects of the space gaining therapy according to Cetlin].

The non extraction technique according to N. Cetlin for the treatment of crowded and protrusive dentitions in class I and class II malocclusions is assessed. The intent of this article is to outline the approach to non extraction treatment with the following major clinical objectives: 1) space gaining in both maxillary and mandibular arches; 2) anchorage preservation throughout treatment and 3) intrusion of the maxillary incisors.

Biomechanical Phenomena↗

Non extraction short-term arch changes.

OBJECTIVES: to examine the Cetlin protocol for short-term dentoalveolar changes in the sagittal and transversal planes in non-extraction treatment. MATERIALS AND METHODS: eighty patients with Class II, div.1 malocclusion treated with the Cetlin protocol, comprising upper distalizing plate, extraoral traction, and lower lip bumper. Dental study models were examined before treatment and after molar Class II correction during which upper molars were mechanically distalized, distobuccally rotated and expanded. RESULTS: the upper arch perimeter increased significantly. The lip bumper produced functional expansion of the lower arch, especially in the transverse plane, with an important increase in the arch perimeter. CONCLUSIONS: in the short-term, the Cetlin protocol made the following improvements: 1) molar correction, 2) resolution or improvement of crowding, 3) space recovery in both arches for leveling the curve of Spee and final adjustments. Further improvements in intercuspation can be made, if necessary, by fixed appliance therapy.

Activator Appliances↗

Nitric oxide generation mediated by beta-adrenoceptors is impaired in platelets from patients with Type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Type 2 diabetic patients have been shown to have reduced basal platelet nitric oxide synthase activity, which is a possible contributor to the vascular complications seen in the disease. We investigated platelet nitric oxide generation stimulated by beta-adrenoceptors and adenylyl cyclase in Type 2 diabetic patients and control subjects. METHODS: Platelets isolated from blood taken from nine Type 2 diabetic patients and nine healthy control subjects of similar age were treated with isoproterenol 1 micro mol/l, forskolin 1 micro mol/l or vehicle. Platelet nitric oxide synthase activity was measured by L-[(3)H]-arginine to L-[(3)H]-citrulline conversion, cyclic GMP content by radioimmunoassay, and nitric oxide synthase type 3 expression by western blotting. RESULTS: Basal platelet nitric oxide synthase activity was lower in diabetic patients than in control subjects (0.01+/-0.02 pmol L-citrulline/10(8) platelets, compared with 0.12+/-0.05; p<0.05), although no corresponding difference was seen in basal platelet cyclic GMP (0.61+/-0.39 and 0.13+/-0.22 pmol cyclic GMP/10(8) platelets respectively; p=0.37). In control subjects isoproterenol 1 micro mol/l and forskolin 1 micro mol/l increased platelet nitric oxide synthase activity (to 0.27+/-0.08 and 0.27+/-0.07 pmol L-citrulline/10(8) platelets respectively; p<0.05 for each in comparison with basal) and cyclic GMP (to 1.84+/-0.41 and 1.86+/-0.48; p<0.05 for each in comparison with basal). This effect was not achieved in diabetic patients. Isoproterenol- and forskolin-stimulated cyclic GMP correlated inversely with plasma glucose and HbA(1c). Platelet nitric oxide synthase type 3 expression was not different in control and diabetic subjects and was not changed by acute exposure of platelets to isoproterenol. CONCLUSIONS/INTERPRETATION: Nitric oxide generation stimulated by beta-adrenoceptors and adenylyl cyclase is impaired in platelets of people with Type 2 diabetes mellitus, with no corresponding change in nitric oxide synthase type 3 expression. It is possible that this impairment contributes to the thrombotic and atherosclerotic complications of Type 2 diabetes.

Angiotensin-Converting Enzyme Inhibitors↗

Maintaining hydraulic control using deep rooted tree systems.

Groundwater phytotechnology systems are currently being used to control the migration of contaminant plumes and remove groundwater that flows into containment areas. Trees in such systems function by reducing recharge and using groundwater via transpiration. A stand of deep-rooted trees can act as a biological "pump", removing a substantial amount of water from the saturated zone. Depth to groundwater compared to rooting depth is an important consideration. Many useful tree species are not naturally deep-rooted, but various cultural practices can produce trees with roots that are deep enough to tap into the water table. Hydraulic control can be calculated or modeled using equations that compare transpired water to groundwater flow and take into account site-specific geologic and climatic variables. However, field measurements should be carried out whenever possible to obtain more precise estimates of groundwater capture and control.

Biodegradation, Environmental↗

Use of fluoxetine for treatment of Machado-Joseph disease: an open-label study.

CONTEXT: Machado-Joseph Disease (MJD/SCA3) is an autosomal dominant spinocerebellar degeneration that evolves to disability and death. Experimental data have shown that serotonin is an important cerebellar neurotransmitter and that impairment of the serotoninergic cerebellar system can induce cerebellar ataxia. OBJECTIVES: To evaluate the efficacy of fluoxetine, a serotonin reuptake inhibitor, in treating neurologic dysfunction in patients with MJD. PATIENTS AND METHODS: Thirteen MJD patients were treated with fluoxetine (20 mg/day) and were followed-up for 6 weeks. Outcome measures included functional capacity, standardized neurologic and cognitive ratings. The Montgomery-Asberg depression rating scale was used to control depressive symptoms. RESULTS: There was no significant improvement in motor abilities after 6 weeks of treatment. CONCLUSIONS: These results suggest that fluoxetine has no benefit in motor function of patients with MJD/SCA3.

Adolescent↗

[Jeiuno-ileal diverticula complicated by perforation. Clinical case].

The diverticular disease is rarely located in the small intestine (0.1-1.4%). The most important feature is due to the lack of a typical symptomatology which may appear only on the occasion of the complications it may incur (perforation, haemorrhage and so on). It isn't also infrequent that the surgeon may observe intestinal diverticula accidentally, on the occasion of laparotomies carried out in emergency or for other pathologies. The literature on intestinal diverticula is reviewed and personal experience in a clinical case presenting as acute abdomen is described.

Abdomen, Acute↗

[Day Surgery. Five years of experience and activity].

BACKGROUND: The aim of this paper is to evaluate the management of an integrated unit of Day Surgery in a General Surgery Department. METHODS: An outline of the first 5 years of activity is presented. Setting of investigation: little provincial hospital. Patients have been selected on a basis of Day Surgery specific features: a total of 1,294 patients. Pathologies treated: inguinal hernias, phlebectasias, phimosis, borsitis, arthritic cysts, tendon cysts, carpal tunnel, Dupuytren's disease ("crispatura tendinum"), lymphadenitis, mammary nodules, hemorrhoids, hydroceles, varicoceles, adipomas. Patients' selection parameters, surgical operation type and modalities, postoperative course, protected discharges from hospital, follow-up and complications have all been carefully recorded. RESULTS: The most numerous operations were related to hernial pathology (54.32%) and to adipomas (10.81%). The form of anesthesia was mainly loco-regional. Only 4 cases (0.3%) had to be hospitalized for the night after operation. COMPLICATIONS: 1 serious wound infection, needing removal of the hernial prosthesis; 1 painful "tumefaction" on the inguinal wound for hernioplastic operation; 3 "seromas" in inguinal hernioplastics. CONCLUSIONS: Advantages of Day-Surgery: cut in health costs due to the reduction of admissions to hospital; reduction in hospital infections and in surgical wounds; reduction in drug use; thinning of waiting lists; increase of available beds for other pathologies; reduction of disability days; high appreciation index.

Adolescent↗

AntiClustal: Multiple Sequence Alignment by antipole clustering and linear approximate 1-median computation.

In this paper we present a new Multiple Sequence Alignment (MSA) algorithm called AntiClusAl. The method makes use of the commonly use idea of aligning homologous sequences belonging to classes generated by some clustering algorithm, and then continue the alignment process ina bottom-up way along a suitable tree structure. The final result is then read at the root of the tree. Multiple sequence alignment in each cluster makes use of the progressive alignment with the 1-median (center) of the cluster. The 1-median of set S of sequences is the element of S which minimizes the average distance from any other sequence in S. Its exact computation requires quadratic time. The basic idea of our proposed algorithm is to make use of a simple and natural algorithmic technique based on randomized tournaments which has been successfully applied to large size search problems in general metric spaces. In particular a clustering algorithm called Antipole tree and an approximate linear 1-median computation are used. Our algorithm compared with Clustal W, a widely used tool to MSA, shows a better running time results with fully comparable alignment quality. A successful biological application showing high aminoacid conservation during evolution of Xenopus laevis SOD2 is also cited.

Algorithms↗

Trinucleotide repeats in 202 families with ataxia: a small expanded (CAG)n allele at the SCA17 locus.

BACKGROUND: Ten neurodegenerative disorders characterized by spinocerebellar ataxia (SCA) are known to be caused by trinucleotide repeat (TNR) expansions. However, in some instances the molecular diagnosis is considered indeterminate because of the overlap between normal and affected allele ranges. In addition, the mechanism that generates expanded alleles is not completely understood. OBJECTIVE: To examine the clinical and molecular characteristics of a large group of Portuguese and Brazilian families with ataxia to improve knowledge of the molecular diagnosis of SCA. PATIENTS AND METHODS: We have (1) assessed repeat sizes at all known TNR loci implicated in SCA; (2) determined frequency distributions of normal alleles and expansions; and (3) looked at genotype-phenotype correlations in 202 unrelated Portuguese and Brazilian patients with SCA. Molecular analysis of TNR expansions was performed using polymerase chain reaction amplification. RESULTS: Patients from 110 unrelated families with SCA showed TNR expansions at 1 of the loci studied. Dominantly transmitted cases had (CAG)(n) expansions at the Machado-Joseph disease gene (MJD1) (63%), at SCA2 (3%), the gene for dentatorubropallidoluysian atrophy (DRPLA) (2%), SCA6 (1%), or SCA7 (1%) loci, or (CTG)(n) expansions at the SCA8 (2%) gene, whereas (GAA)(n) expansions in the Freidreich ataxia gene (FRDA) were found in 64% of families with recessive ataxia. Isolated patients also had TNR expansions at the MJD1 (6%), SCA8 (6%), or FRDA (8%) genes; in addition, an expanded allele at the TATA-binding protein gene (TBP), with 43 CAGs, was present in a patient with ataxia and mental deterioration. Associations between frequencies of SCA2 and SCA6 and a frequency of large normal alleles were found in Portuguese and Brazilian individuals, respectively. Interestingly, no association between the frequencies of DRPLA and large normal alleles was found in the Portuguese group. CONCLUSIONS: Our results show that (1) a significant number of isolated cases of ataxia are due to TNR expansions; (2) expanded DRPLA alleles in Portuguese families may have evolved from an ancestral haplotype; and (3) small (CAG)(n) expansions at the TBP gene may cause SCA17.

Adenine↗

Influence of sialic acid content of low-density lipoprotein particles on endothelium-dependent vasorelaxation in rabbit aorta.

Low-density lipoprotein (LDL) concentration in plasma is an important predictor for atherosclerosis, and desialylated LDL has been proposed to be particularly atherogenic. Atherosclerosis is also associated with vascular endothelial dysfunction. We therefore wished to test the hypothesis that removal of sialic acid residues from LDL increases its ability to inhibit endothelium-dependent vasorelaxation. We studied vasorelaxant responses to acetylcholine (ACh) in isolated rabbit aortic rings as a model of endothelium-dependent relaxation, in the presence or absence of LDL treated either with saline or with neuraminidase, to cleave sialic acid residues. Vasorelaxant responses to ACh were inhibited by 300 microg protein per ml saline-treated LDL (E(max) 77.5+/-4.5 vs. 89.7+/-2.2% in the absence of LDL, P<0.05). This inhibitory effect was not altered by neuraminidase treatment of LDL. In contrast, 300 microg protein per ml LDL, either saline- or neuraminidase-treated, did not affect vasorelaxant responses to the endothelium-independent dilator sodium nitroprusside. We found no correlation between sialic acid content of saline-treated LDL and its ability to inhibit endothelium-dependent vasorelaxation, in rabbit aortic rings, at a concentration of 300 microg protein per ml. Our results therefore suggest that sialic acid content is not an important determinant of the effect of LDL on vascular endothelium-dependent relaxation.

Acetylcholine↗

Improvement in the molecular diagnosis of Machado-Joseph disease.

BACKGROUND: Direct detection of the gene mutation allows for the confirmation of the clinical diagnosis of Machado-Joseph disease (MJD), the most frequent cause of autosomal dominant spinocerebellar ataxia worldwide. OBJECTIVE: To address the main difficulties in our national MJD predictive testing program. The first was the emergence of intermediate alleles, for which it is not yet possible to determine whether they will cause disease. The second was the issue of homoallelism, ie, homozygosity for 2 normal alleles with exactly the same (CAG)(n) length, which occurs in about 10% of all test results. METHODS: A large pedigree with 1 affected patient carrying a 71 and a 51 CAG repeat and 2 asymptomatic relatives carrying the 51 CAG repeat and normal-size alleles underwent clinical and molecular studies. Intragenic haplotypes for these alleles were determined. A representative sample of the healthy population in the region was obtained to assess the distribution of the normal (CAG)(n) length. We established the genotype for 4 intragenic polymorphisms in the gene for MJD (MJD1) in 21 homoallelic individuals, to distinguish their 2 normal chromosomes. In addition, we developed a new Southern blot method to completely exclude cases of nonamplification of expanded alleles in the homoallelic individuals. RESULTS: The study of the family in which the 51 CAG repeat was found suggests that the allele is apparently not associated with disease. These intermediate alleles were not present in a large sample of the healthy population from the same region. Intragenic polymorphisms allowed distinction of the 2 different normal alleles in all cases of homoallelism. The absence of an expanded allele was also confirmed by Southern blot. CONCLUSIONS: We propose an improved protocol for molecular testing for MJD. These strategies, developed to overcome the practical difficulties mostly in the presymptomatic and prenatal diagnosis of MJD, should prove useful for other polyglutamine-related disorders.

Adult↗

Neurologic findings in Machado-Joseph disease: relation with disease duration, subtypes, and (CAG)n.

CONTEXT: Machado-Joseph disease (MJD), an autosomal dominant spinocerebellar degeneration caused by an expanded CAG repeat on chromosome 14q32.1, is a heterogeneous disorder for clinical manifestations. The reasons for the wide range of neurologic findings in this disease are poorly understood. OBJECTIVE: To explain part of this heterogeneity through the association of the neurologic findings with sex, disease duration, age of onset, clinical type, and size of CAG repeat expansion. DESIGN: A case-control study. SETTING: Ambulatory care. PATIENTS: A consecutive sample of 62 patients with MJD. MAIN OUTCOME MEASURE: Neurologic signs. RESULTS: A direct relationship was found between the disease duration and severity of gait and limb ataxia, dysarthria, dysphagia, fasciculations, pyramidal syndrome, and ophthalmoplegia (P<.02). The most severe forms of nuclear ophthalmoplegia were associated with type 1 MJD, whereas those of supranuclear ophthalmoplegia were associated with type 3 MJD (P<.001). It was also found that higher mean (CAG)(n) lengths were associated with worse degrees of the pyramidal syndrome and dystonia (P<.001). The presence and severity of nystagmus, eyelid retraction, rigidity and/or bradykinesia, and optic atrophy were not clearly associated with any of the predictive variables under study. CONCLUSIONS: Disease duration can explain part of the heterogeneity of ataxia, dysarthria, dysphagia, fasciculations, pyramidal syndrome, and ophthalmoplegia, in MJD. Type 1 MJD was positively associated with nuclear ophthalmoplegia; type 3 MJD was positively associated with supranuclear ophthalmoplegia. Higher mean CAG lengths were found to correlate with the pyramidal syndrome and dystonia. Nystagmus, eyelid retraction, rigidity and/or bradykinesia, and optic atrophy were hardly attributable to any known reason or variable.

Adult↗

A survey of spinocerebellar ataxia in South Brazil - 66 new cases with Machado-Joseph disease, SCA7, SCA8, or unidentified disease-causing mutations.

BACKGROUND: The autosomal dominant spinocerebellar ataxias (SCAs) are a clinical and genetically heterogeneous group of debilitating, neurodegenerative diseases, related to fourteen different loci - SCAs 1, 2, 4, 5, 6, 7, 8, 10, 11,12,13 and 14, Machado-Joseph disease (MJD/SCA 3), and DRPLA. OBJECTIVES: (1) To verify the frequency of SCA1, SCA2, MJD, DRPLA, SCA6, SCA7 and SCA8 in a series of new SCA patients from South Brazil and (2) to compare their molecular and clinical characteristics with other patients previously described. METHODS: Sixty-six cases were included in the present study: 52 were familial and 14 sporadic. Molecular analysis of the trinucleotide repeat loci were performed according to methods in the literature. RESULTS: 92% of families with autosomal dominant inheritance segregated the MJD1 mutation,2% of families segregated the SCA7 mutation and 6% remained undiagnosed. Among 14 isolated cases, one showed the SCA8 mutation. Clinical and molecular findings were similar to those already described in the literature, but revealed (1) one SCA7 patient with eyelid retraction, a sign usually related to MJD; and (2) one sporadic case of SCA8. CONCLUSIONS: The proportion of MJD cases was very high, probably reflecting an Azorean founder effect. The estimated frequency of affected individuals with MJD, in our region, was 1.8 / 100,000, and of SCAs other than MJD, 0.2/100,000.

Adult↗

Angiogenesis and antiangiogenic agents in non-small cell lung cancer.

Tumour angiogenesis is the result of the imbalance between a large number of mediators with angiogenic and antiangiogenic activity. It may be a very early process in vivo and it may follow different pathways in different organs. Moreover, different roles of angiogenic molecules have been observed in normal and neoplastic lung and striking differences between non-small cell lung carcinomas (NSCLC) and SCLC have been observed. Contradictory results are reported in the literature on the association of angiogenesis with poor prognosis in NSCLC. Among the currently available antiangiogenic therapies, the inhibitors of vascular endothelial growth factor (VEGF), and their receptor (VEGFR) and matrix metallo-proteinase (MMP), some antivascular agents and the antiangiogenic scheduling of chemotherapy are beginning to show clinical efficacy. The best use of the antiangiogenic therapies will probably be in presence of low tumour burdens and in association with chemotherapy. However, new surrogate markers of tumour response have to be defined.

Angiogenesis Inducing Agents↗

Machado-Joseph disease in South Brazil: clinical and molecular characterization of kindreds.

OBJECTIVE: To examine the clinical, genetic, and molecular characteristics of a group of MJD patients recently identified in the southernmost state of Brazil, and compare these data with studies from the literature. METHODS: Some 62 individuals from 35 families, mostly of Azorean ancestry, had their clinical data and their MJD1 expanded regions examined. RESULTS: The present patients had an earlier age of onset, on average, than Portuguese-Azorean cases. Their survival, proportion of types, average anticipation, proportion of affected versus non-affected siblings, neurological signs and molecular findings are similar to those observed in patients previously described. Type 1 patients with male transmission showed worse anticipations than type 1 patients with female transmission. Patients with type 1 had also larger CAG expansions than other patients. CONCLUSIONS: The Brazilian origin seemed to affect the age of onset. We also noted that there were no differences other than the neurological between types 2 or 3, since both are similar in age of onset, disease duration and length of CAG repeats. We addressed the question of maintaining or not subtypes 2 and 3 separated, among patients with genetic and geographical backgrounds like the presented patients here.

Adolescent↗

[Genotype characterization of hepatitis C virus infection in children].

Hepatitis C virus (HCV) infection in children was assessed by RT-nested PCR of the 5'untranslated region (5'UTR) of the viral genome combined with virus genotyping, performed by restriction fragment length polymorphism (RFLP). We analysed HCV infection in 64 children and in 9 HCV chronically infected mothers corresponding to 10 of them. Thirty two children were positive for serum HCV RNA as determined by RT-nested PCR. The viremia was analysed in consecutive samples of 25 children. Nine children (36%) were always positive for HCV RNA, in 5 (20%) a positive RT-nested PCR turned negative in subsequent samples, other 9 (36%) showed alternating RT-nested PCR results and in 2 (8%) the RT-nested PCR turned positive after an initial negative result. The HCV genotype distribution was studied in 27/32 children and in 9 mothers, and it was similar to that reported in the literature for adult and pediatric patients in our country. Genotype 1 was predominant in our population. HCV genotype did not change in the same patient during the time of this study. HCV genotype was the same in mother-infant pairs. We could not establish a correlation between HCV genotype and vertical transmission of HCV. This study will be helpful to further analyze HCV behavior during pediatric infection and the host's response in the initial stages of it.

Adolescent↗