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1.
Hand (N Y) ; : 15589447231185581, 2023 Jul 23.
Article in English | MEDLINE | ID: mdl-37482750

ABSTRACT

BACKGROUND: Dupuytren is a fibroproliferative pathology leading to contracture of the palmar fascia. Several approaches have been described for the surgical treatment with partial fasciectomy with few comparisons in literature. Our purpose is to compare the functional outcomes between the partial fasciectomy performed by Bruner type incision and zetaplasty incision. METHODS: The method used was a randomized clinical trial including adult patients of both sexes with surgical indication for Dupuytren disease presented to a reference center. Patients were randomly and consecutively allocated in the groups 1:1. We recorded the Disabilities of the Arm, Shoulder, and Hand (DASH) score; range of motion for active and passive extension of the metacarpophalangeal (MP) and proximal interphalangeal (PIP) joints; visual analog scale for pain; and complications. RESULTS: In all, 62 patients were included, with 48 patients reaching the minimum follow-up of 6 months with 63 operated fingers. In the Bruner approach group, we obtained a correction of the active and passive extension of the MP of 28° and of the PIP of 23°. In the zetaplasty group, correction of MP was 30° for active and passive, and 18° for active extension and 16° for passive extension of the PIP. The reduction in the DASH score was 10 points in the Bruner group and 22 points in the zetaplasty group. There was no statistically significant effect of the type of treatment on preoperative and postoperative differences in any of the parameters evaluated. CONCLUSIONS: There were no statistically significant differences between the 2 techniques for self-reported functional outcomes or objective measures of physical examination.

2.
Pesqui. vet. bras ; 38(6): 1225-1231, jun. 2018. tab
Article in English | LILACS, VETINDEX | ID: biblio-955457

ABSTRACT

For the evaluation of serum biochemical parameters of Pêga breed donkeys (Equus asinus), for the different age groups and sex, blood samples of 123 animals were analyzed, of 29 males aged from 8 days to 10 years and of 94 females (15 lactating) aged from 2 days to 12 years, from two farms in the central-southern Minas Gerais, Brazil. The donkeys were divided by age into 5 groups: Group 1 (≤6 months), Group 2 (7-12 months), Group 3 (13-48 months), Group 4 (49-72 months), and Group 5 (≥73 months). According to the sex, they were divided into two groups, males and females. Serum biochemical elements: total protein, albumin, globulin, the A:G ratio, cholesterol, triglycerides, uric acid, creatinine, urea, phosphorus, calcium, Ca:P ratio, magnesium, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) and creatine kinase (CK), were evaluated in all animals. No significant differences were found for globulins, uric acid, urea and A:G ratio between age groups. Group 4 showed the highest values for total protein when compared with animals in Group 1 and 2. In Goup 2, the donkeys showed albumin levels lower than Group 3 and 4. Group 1 they had cholesterol levels higher than those in Group 2 and 4, and similar of the other groups. Higher phosphorus serum concentration was observed in Group 1. Calcium was significantly lower in Group 2. The Ca:P ratio was higher for Group 5. The magnesium values were significantly higher in donkeys older than 49 months (Group 4 and 5). The value of AST was lower for group 1. The ALP enzyme was significantly higher in younger animals up to 12 months, followed by gradual decrease with advancing age. The values of GGT were higher in donkeys up to 6 months, followed by decreasing values for subsequent groups. No differences were found between genders for albumin, cholesterol, creatinine, urea, uric acid, Ca:P ratio, magnesium, ALT, AST, and alkaline phosphatase. Females had higher values for total protein, globulin and triglycerides. Males showed higher values for A:G ratio, phosphorus, calcium and CK. The results showed that age and sex can influence serum biochemical values of Pêga breed donkeys.(AU)


Para a avaliação dos parâmetros bioquímicos séricos de jumentos (Equus asinus) da raça Pêga, quanto às diferentes faixas etárias e sexo, foram analisadas amostras sanguíneas de 123 animais, sendo 29 machos com idades de 8 dias a 10 anos e 94 fêmeas (15 lactantes) de 2 dias a 12 anos, de dois criatórios na região centro-sul do estado de Minas Gerais. Os animais foram divididos em 5 grupos de acordo com as idades: Grupo 1 (≤6 meses); Grupo 2 (7-12 meses); Grupo 3 (13-48 meses); Grupo 4 (49-72 meses) e Grupo 5 (≥73 meses). De acordo com o sexo, foram divididos em dois grupos, machos e fêmeas. Para todos os animais foram realizadas as análises de proteínas totais, albumina, globulinas, relação A:G, colesterol, triglicérides, ácido úrico, creatinina, ureia, fósforo, cálcio, relação Ca:P, magnésio, alanina aminotransferase (ALT), aspartato aminotransferase (AST), fosfatase alcalina (FAL), gama glutamiltransferase (GGT) e creatina quinase (CK). Não foram encontradas diferenças significativas para os elementos globulinas, ácido úrico, ureia e relação A:G entre as faixas etárias. O Grupo 4 apresentou os maiores valores para proteínas totais quando comparados aos animais dos grupos 1 e 2. Os animais do Grupo 2 mostraram valores de albumina inferiores aos Grupos 3 e 4. Os animais do Grupo 1 apresentaram valores de colesterol superiores aos do Grupo 2 e 4, e semelhante aos demais grupos. Maior concentração sérica de fósforo foi observada nos animais do grupo 1. O cálcio apresentou valor significativamente menor no Grupo 2. A relação Ca:P foi maior para o grupo 5. Os valores do magnésio foram estatisticamente superiores nos animais com idade superior a 49 meses (Grupos 4 e 5). O valor da AST foi menor para o Grupo 1.As enzimas FAL apresentaram valor significativamente maior nos animais mais jovens até 12 meses, seguida de redução gradual com o avançar da idade. Os valores da GGT foi maior nos jumentos com até seis meses de idade, seguido de valores decrescentes para os grupos subsequentes. Não foram encontradas diferenças entre os sexos para albumina, colesterol, creatinina, ureia, ácido úrico, relação Ca:P, magnésio, ALT, AST e fosfatase alcalina. As fêmeas tiveram valores maiores para proteínas totais, globulinas e triglicérides. Os machos mostraram maiores valores para relação A:G, fósforo, cálcio e CK. Pelos resultados nota-se que a idade e o sexo podem influenciar nos valores bioquímicos séricos dos jumentos da raça Pêga.(AU)


Subject(s)
Animals , Biochemistry/classification , Equidae/embryology
4.
BMC Musculoskelet Disord ; 15: 65, 2014 Mar 05.
Article in English | MEDLINE | ID: mdl-24597699

ABSTRACT

BACKGROUND: Various treatments are available for reducible unstable fractures of the distal radius, such as closed reduction combined with fixation by external fixator (EF), and rigid internal fixation using a locked volar plate (VP). Although there are studies comparing these methods, there is no conclusive evidence indicating which treatment is best. The hypothesis of this study is that surgical treatment with a VP is more effective than EF from the standpoint of functional outcome (patient-reported). METHODS/DESIGN: The study is randomized clinical trial with parallel groups and a blinded evaluator and involves the surgical interventions EF and VP. Patients will be randomly assigned (assignment ratio 1:1) using sealed opaque envelopes. This trial will include consecutive adult patients with an acute (up to 15 days) displaced, unstable fracture of the distal end of the radius of type A2, A3, C1, C2 or C3 by the Arbeitsgemeinschaft für Osteosynthesefragen-Association for the Study of Internal Fixation classification and type II or type III by the IDEAL32 classification, without previous surgical treatments of the wrist. The surgical intervention assigned will be performed by three surgical specialists familiar with the techniques described. Evaluations will be performed at 2, and 8 weeks, 3, 6 and 12 months, with the primary outcomes being measured by the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire and measurement of pain (Visual Analog Pain Scale and digital algometer). Secondary outcomes will include radiographic parameters, objective functional evaluation (goniometry and dynamometry), and the rate of complications and method failure according to the intention-to-treat principle. Final postoperative evaluations (6 and 12 months) will be performed by independent blinded evaluators. For the Student's t-test, a difference of 10 points in the DASH score, with a 95% confidence interval, a statistical power of 80%, and 20% sampling error results in 36 patients per group. DISCUSSION: Results from this study protocol will improve the current evidence regarding to the surgical treatment these fractures. TRIAL REGISTRATION: ISCRTN09599740.


Subject(s)
Bone Plates , External Fixators , Fracture Fixation/methods , Radius Fractures/surgery , Adult , Clinical Protocols , Female , Follow-Up Studies , Fracture Fixation/instrumentation , Fracture Fixation, Internal , Humans , Male , Patient Selection , Radiography , Radius Fractures/diagnostic imaging , Recovery of Function , Severity of Illness Index , Single-Blind Method , Visual Analog Scale
5.
ISRN Mol Biol ; 2014: 828102, 2014.
Article in English | MEDLINE | ID: mdl-27335680

ABSTRACT

The aim of this study was to use multiple DNA markers for detection of QTLs related to resistance to white mold in an F2 population of common bean evaluated by the straw test method. The DNA from 186 F2 plants and from the parents was extracted for genotypic evaluation using SSR, AFLP, and SRAP markers. For phenotypic analysis, 186 F2:4 progenies and ten lines were evaluated, in a 14 × 14 triple lattice experimental design. The adjusted mean values of the F2:4 progenies were used for identification of QTLs by Bayesian shrinkage analysis. Significant differences were observed among the progenies for reaction to white mold. In identification of QTLs, 17 markers identified QTLs for resistance-13 SSRs and 4 AFLPs. The moving away method under the Bayesian approach proved to be efficient in the identification of QTLs when a genetic map is not used due to the low density of markers. The ME1 and BM211 markers are near the QTLs, with the effect of increasing resistance to white mold, and they have high heritability. They are thus promising for marker-assisted selection.

6.
Trials ; 14: 246, 2013 Aug 07.
Article in English | MEDLINE | ID: mdl-23924198

ABSTRACT

BACKGROUND: Humeral shaft fractures account for 1 to 3% of all fractures in adults and for 20% of all humeral fractures. Non-operative treatment is still the standard treatment of isolated humeral shaft fractures, although this method can present unsatisfactory results. Surgical treatment is reserved for specific conditions. Modern concepts of internal fixation of long bone shaft fractures advocate relative stabilisation techniques with no harm to fracture zone. Recently described, minimally invasive bridge plate osteosynthesis has been shown to be a secure technique with good results for treating humeral shaft fractures. There is no good quality evidence advocating which method is more effective. This randomised controlled trial will be performed to investigate the effectiveness of surgical treatment of humeral shaft fractures with bridge plating in comparison with conservative treatment with functional brace. METHODS/DESIGN: This randomised clinical trial aims to include 110 patients with humeral shaft fractures who will be allocated after randomisation to one of the two groups: bridge plate or functional brace. Surgical treatment will be performed according to technique described by Livani and Belangero using a narrow DCP plate. Non-operative management will consist of a functional brace for 6 weeks or until fracture consolidation. All patients will be included in the same rehabilitation program and will be followed up for 1 year after intervention. The primary outcome will be the DASH score after 6 months of intervention. As secondary outcomes, we will assess SF-36 questionnaire, treatment complications, Constant score, pain (Visual Analogue Scale) and radiographs. DISCUSSION: According to current evidence shown in a recent systematic review, this study is one of the first randomised controlled trials designed to compare two methods to treat humeral shaft fractures (functional brace and bridge plate surgery).


Subject(s)
Bone Plates , Braces , Fracture Fixation, Internal/instrumentation , Humeral Fractures/surgery , Osseointegration , Research Design , Brazil , Clinical Protocols , Equipment Design , Fracture Fixation, Internal/adverse effects , Fracture Fixation, Internal/rehabilitation , Fracture Healing , Humans , Humeral Fractures/diagnosis , Pain Measurement , Predictive Value of Tests , Prosthesis Design , Surveys and Questionnaires , Time Factors , Treatment Outcome
7.
Hand (N Y) ; 8(1): 60-3, 2013 Mar.
Article in English | MEDLINE | ID: mdl-24426894

ABSTRACT

This aim of this study was to evaluate the progression of grip, tip pinch, key (lateral) pinch, and tripod pinch strengths in patients suffering from carpal tunnel syndrome with thenar atrophy following surgery. Between October 2008 and May 2010, 46 patients (49 hands) with carpal tunnel syndrome associated with thenar atrophy underwent surgery. Thenar atrophy was assessed by clinical inspection. Evaluations for grip strength and for tip, key, and tripod pinch strengths were made using a hydraulic hand dynamometer grip and a hydraulic pinch gauge, respectively. These measurements were taken before surgery and at 3 and 6 months after the procedure. When we compared the averages of all forces measured in the affected hand before the surgery with all forces measured at 3 months postoperative, we found no significant differences. However, after 6 months, we found significant differences for all four strength tests as compared with those measurements taken preoperatively and at the 3 month time point. Our results suggest that patients with thenar atrophy show increased grip strength and pinch strength by the sixth month after surgical treatment.

8.
Rheumatology (Oxford) ; 51(1): 93-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22039269

ABSTRACT

OBJECTIVE: The aim of this study is to evaluate the effectiveness of CS injection, percutaneous pulley release and conventional open surgery for treating trigger finger in terms of cure, relapse and complication rates. METHODS: One hundred and thirty-seven patients with a total of 150 fingers were randomly assigned and allocated into one of the treatment groups, with treatments allocated into 150 opaque and sealed envelopes. We included patients >15 years of age with a trigger on any finger of the hand (Types II-IV) and used a minimum follow-up time of 6 months. The primary outcome measures were cures, relapses and failures. RESULTS: Forty-nine patients were assigned to the conservative group to undergo CS injections, whereas 45 and 56 were assigned to undergo percutaneous release and outpatient open surgery, respectively. The trigger cure rate for patients in the injection method group was 57%, and wherever necessary, two injections were administered, which increased the cure rate to 86%. For the percutaneous and open release methods, remission of the trigger was achieved in all cases. CONCLUSIONS: The percutaneous and open surgery methods displayed similar effectiveness and proved superior to the conservative CS method regarding the trigger cure and relapse rates. Trial registration. Current Controlled Trials, http://www.controlled-trials.com/, ISRCTN19255926.


Subject(s)
Glucocorticoids/administration & dosage , Minimally Invasive Surgical Procedures/methods , Orthopedic Procedures/methods , Trigger Finger Disorder/drug therapy , Trigger Finger Disorder/surgery , Adolescent , Adult , Aged , Female , Glucocorticoids/adverse effects , Glucocorticoids/therapeutic use , Humans , Injections, Intralesional , Male , Methylprednisolone/administration & dosage , Methylprednisolone/adverse effects , Methylprednisolone/analogs & derivatives , Methylprednisolone/therapeutic use , Methylprednisolone Acetate , Middle Aged , Minimally Invasive Surgical Procedures/adverse effects , Orthopedic Procedures/adverse effects , Pain/etiology , Range of Motion, Articular , Recurrence , Treatment Outcome , Young Adult
9.
J Hand Surg Am ; 36(3): 464-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21277697

ABSTRACT

PURPOSE: The objectives of this study were to evaluate palmar surface parameters to identify the exact location of the proximal edge of the flexor tendon A1 pulley relative to the digital palmar crease of the index, middle, ring, and little fingers and to evaluate the length of this pulley. METHODS: We studied 280 fingers on 70 hands from 35 fresh human cadavers, initially by measuring the distance between the digital-palmar and proximal interphalangeal creases (measure A), followed by dissection of the fingers and measurement of the distance between the proximal edge of the A1 pulley and the digital-palmar crease (measure B) and the length of the A1 pulley (measure C). We carried out statistical analysis using Hotelling's multivariate T(2)-test and the paired-samples t-test. RESULTS: We found no statistically significant difference between measures A and B in each finger (p > .05). The mean lengths, in tenths of millimeters, were as follows: measure A: index finger 22.0 mm, middle finger 24.4 mm, ring finger 22.0 mm, and little finger 17.9 mm; measure B: index finger 21.9 mm, middle finger 24.2 mm, ring finger 22.3 mm, and little finger 18.1 mm. The average lengths of the A1 pulley were: index finger 9.8 mm, middle finger 10.7 mm, ring finger 9.6 mm, and little finger 8.1 mm. CONCLUSIONS: The distance between the digital-palmar and proximal interphalangeal creases may be used as a cutaneous landmark on the palmar surface for the exact location of the proximal edge of the A1 pulley in the palm of the hand, thereby ensuring greater safety in surgical procedures such as percutaneous release of trigger finger.


Subject(s)
Fingers/anatomy & histology , Tendons/anatomy & histology , Body Weights and Measures , Cadaver , Dissection , Female , Finger Joint/anatomy & histology , Finger Joint/physiology , Humans , Ligaments/anatomy & histology , Male , Range of Motion, Articular/physiology , Skin/anatomy & histology
10.
Hand (N Y) ; 6(1): 80-4, 2011 Mar.
Article in English | MEDLINE | ID: mdl-22379444

ABSTRACT

Melorheostosis of the hand is rare. We report a 28-year-old woman with persistent pain associated with a slowly growing mass on the dorsum of the right thumb. The radiographs, computed tomography, and magnetic resonance imaging were used to examine characteristic of melorheostosis involving the trapezium bone, first metacarpal, and proximal phalange. The lesions underwent a surgical debulking of the hyperostotic cortex and a cortical fenestration.

11.
BMC Musculoskelet Disord ; 11: 137, 2010 Jun 29.
Article in English | MEDLINE | ID: mdl-20587064

ABSTRACT

BACKGROUND: At present, there is no conclusive evidence regarding the best treatment method for reducible unstable fractures of the distal radius. This study compared the effectiveness of two methods used in surgical treatment of such fractures: percutaneous pinning and external fixation. METHODS: We randomly allocated 100 patients into two groups treated surgically with modified De Palma percutaneous pinning and bridging external fixation. Independent but not blinded evaluators administered the DASH quality-of-life questionnaire at postoperative months 6 and 24, performed functional assessment of pain, range of motion, and palm grip strength, and radiographic examinations (volar and radial angle, and height of the radius) before the operation, immediately afterwards, and at 6 and 24 months postoperative. Modified De Palma percutaneous pinning patients used an above-elbow cast whereas external fixation group had unrestricted elbow motion after surgery. Patients who for any reason demonstrated treatment failure or required additional interventions were followed up and their results were included in the group into which these patients had initially been randomised according to the intention-to-treat principle. A significance level of 5% (alpha = 0.05). was used for all statistical tests, such that tests presenting a p-value less than 0.05 were considered statistically significant. RESULTS: Ninety one (58.8 mean age and 66 participants were female) were included in the final assessment at 24 months. The DASH questionnaire evaluation showed a statistically significant result favouring the De Palma group (mean difference = -7.1 p = 0.044) after six months, but this was not maintained at 24 months. There were no statistically differences between the groups with respect to palm grip strength. Analysis of the range-of-motion limitation index (uninjured side minus affected side motion of) showed a statistical difference (mean difference = 2.4 p = 0.043) favoring the external fixator group with regard to the supination movement 6 months after the operation; however, this was not maintained at 24 months. The final results of the radiographic evaluation were similar for the two groups. Overall, five patients developed complications: two with De Palma pinning and three with external fixation. CONCLUSION: There was a small statistically significant difference favouring the De Palma method in early functional at 6 months according to the DASH questionnaire, and for supination movement favouring the fixator group. However, both were not clinical relevant. By 24 months the groups were similar for all outcomes TRIAL REGISTRATION: Current Controlled Trials ISRCTN04892785.


Subject(s)
Bone Nails , External Fixators , Fracture Fixation/instrumentation , Radius Fractures/surgery , Radius/injuries , Radius/surgery , Adult , Aged , Bone Nails/standards , External Fixators/standards , Female , Fracture Fixation/methods , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures/instrumentation , Minimally Invasive Surgical Procedures/methods , Outcome Assessment, Health Care , Radiography , Radius/pathology , Radius Fractures/diagnostic imaging , Radius Fractures/pathology , Range of Motion, Articular/physiology , Severity of Illness Index , Surveys and Questionnaires , Treatment Outcome
12.
BMC Musculoskelet Disord ; 10: 120, 2009 Oct 01.
Article in English | MEDLINE | ID: mdl-19793401

ABSTRACT

BACKGROUND: Fractures of the proximal radius need to be classified in an appropriate and reproducible manner. The aim of this study was to assess the reliability of the three most widely used classification systems. METHODS: Elbow radiographs images of patients with proximal radius fractures were classified according to Mason, Morrey, and Arbeitsgemeinschaft für osteosynthesefragen/Association for the Study of Internal Fixation (AO/ASIF) classifications by four observers with different experience with this subject to assess their intra- and inter-observer agreement. Each observer analyzed the images on three different occasions on a computer with numerical sequence randomly altered. RESULTS: We found that intra-observer agreement of Mason and Morrey classifications were satisfactory (kappa = 0.582 and 0.554, respectively), while the AO/ASIF classification had poor intra-observer agreement (kappa = 0.483). Inter-observer agreement was higher in the Mason (kappa = 0.429-0.560) and Morrey (kappa = 0.319-0.487) classifications than in the AO/ASIF classification (kappa = 0.250-0.478), which showed poor reliability. CONCLUSION: Inter- and intra-observer agreement of the Mason and Morey classifications showed overall satisfactory reliability when compared to the AO/ASIF system. The Mason classification is the most reliable system.


Subject(s)
Radius Fractures/classification , Radius Fractures/diagnostic imaging , Humans , Radiography , Reproducibility of Results
13.
Am J Trop Med Hyg ; 80(1): 146-51, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19141853

ABSTRACT

Information on malaria-associated anemia in adult patients is scarce in South American populations. From 2004 to 2006, malaria patients 18 to 45 years of age were recruited in a descriptive cross-sectional study from two different towns: Manaus, in the Brazilian Amazon (120 patients) where Plasmodium falciparum incidence is lower ( approximately 20%), and in Tumaco on the Colombian Pacific Coast (126 patients) where P. falciparum incidence is higher ( approximately 90%). Relationships between hematologic parameters and independent variables were explored using cross-tabulations and multiple linear regression analyses. We found an inverse relationship of hemoglobin (Hb) levels with days of illness in both sites. In Manaus but not in Tumaco, red cell distribution width (RDW) was related to asexual parasitemia. Reticulocytes were higher in Plasmodium vivax infection in Tumaco. Only in Tumaco, two patients with P. falciparum infection presented with severe anemia (Hb < 7 g/dL). Etiologic factors associated with hematologic changes in malaria seem to be multifactorial. More studies are needed to clarify the anemia determinants in uncomplicated malaria in South America, where malaria transmission is mostly unstable.


Subject(s)
Malaria/blood , Malaria/transmission , Adolescent , Adult , Anemia/blood , Anemia/etiology , Brazil , Colombia , Erythrocyte Count , Geography , Humans , Leukocyte Count , Malaria, Falciparum/blood , Malaria, Falciparum/transmission , Malaria, Vivax/blood , Malaria, Vivax/transmission , Middle Aged , Reticulocyte Count , Young Adult
14.
J Shoulder Elbow Surg ; 16(1): 112-4, 2007.
Article in English | MEDLINE | ID: mdl-17055749

ABSTRACT

The biomechanical importance of the costoclavicular ligament is well known; however, an extensive debate still exists regarding the amount of the medial clavicle that can be removed without injuring the ligament. The goal of this anatomic study in fresh cadavers is to measure the distance between the inferior articular surface of the medial clavicle and the most medial clavicular insertion of the costoclavicular ligament, as well as to verify whether there is a relationship between this measurement and the length of the clavicle. Dissection of 100 shoulders from 50 fresh cadavers was performed. All specimens were from male cadavers ranging in age from 17 to 65 years (mean, 37 years). Variation in clavicular length did not alter the distance between the inferior articular surface of the medial clavicle and the most medial clavicular insertion of the costoclavicular ligament, which in our study measured 1.26 cm. The costoclavicular ligament can extend as far as the inferior articular surface of the medial clavicle. We recommend identification of this ligament during surgeries for resection of the clavicle's proximal extremity.


Subject(s)
Clavicle/anatomy & histology , Clavicle/surgery , Adolescent , Adult , Aged , Cadaver , Humans , Male , Middle Aged
15.
J Chem Inf Model ; 45(3): 645-51, 2005.
Article in English | MEDLINE | ID: mdl-15921454

ABSTRACT

This paper describes the use of artificial neural networks as a theoretical tool in the structural determination of alkaloids from (13)C NMR chemical shift data, aiming to identify skeletal types of those compounds. For that, 162 aporphine alkaloids belonging to 12 different skeletons were codified with their respective (13)C NMR chemical shifts. Each skeleton pertaining to aporphine alkaloid type was used as output, and the (13)C NMR chemical shifts were used as input data of the net. Analyzing the obtained results, one can then affirm the skeleton to which each one of these compounds belongs with high degree of confidence (over 97%). The relation between the correlation coefficient and the number of epochs and the architecture of net (3-layer MLP or 4-layer MLP) were analyzed, too. The analysis showed that the results predicted by the 3-layer MLP networks trained with a number of the epochs higher than 900 epochs are the best ones. The artificial neural nets were shown to be a simple and efficient tool to solve structural elucidation problems making use of (13)C NMR chemical shift data, even when a similarity between the searched skeletons occurs, offering fast and accurate results to identification of skeletons of organic compounds.


Subject(s)
Alkaloids/chemistry , Aporphines/chemistry , Magnetic Resonance Spectroscopy
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