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1.
Ann Chir Plast Esthet ; 67(3): 162-166, 2022 Jun.
Artigo em Francês | MEDLINE | ID: mdl-35067363

RESUMO

Thigh loss cover after carcinologic resection of sarcomas can be complex and compromise the vascular tree of the lower limb. We report a case of a patient with recurrent sarcoma of the right thigh. After multiple resections, the femur and hip joint are exposed. The superficial and deep femoral vessels are taken in the excisional piece. The reconstruction is performed by a free musculocutaneous latissimus dorsi flap, anastomosed to the deep inferior controlateral epigastric vessels. The deep inferior epigastric vessels are of sufficient length to join the contralateral hemiabdomen after dissection with a gauge allowing microsurgical anastomoses. They can serve as recipient vessels for a flap covering the contralateral thigh.


Assuntos
Retalhos de Tecido Biológico , Mamoplastia , Sarcoma , Retalhos de Tecido Biológico/cirurgia , Humanos , Extremidade Inferior/cirurgia , Recidiva Local de Neoplasia/cirurgia , Sarcoma/cirurgia , Coxa da Perna/cirurgia
2.
Ann Chir Plast Esthet ; 66(3): 217-222, 2021 Jun.
Artigo em Francês | MEDLINE | ID: mdl-33431220

RESUMO

INTRODUCTION: Medical photography, ubiquitous in plastic surgery, provides essential information to the medical record. Smartphones have become the preferred tool for acquiring these photographs, but cause a data security issue. Furthermore, the management of photographs is frequently manual and time-consuming. The Pixacare software suite has been designed to meet this need in complete security. It includes a mobile application, a web application and a HADS server. The objective of the study was to calculate the time saved by the Pixacare application at the time of data acquisition. PATIENTS AND METHODS: This prospective and monocentric study was carried out in two steps in order to time the acquisition times with the usual method and with the Pixacare mobile application. Each phase included 89 patients recruited in plastic and maxillofacial surgery consultation with four surgeons. The number of patients and the average number of photographs per patient were comparable for each practitioner in both phases. RESULTS: The acquisition time of the photographic data was divided by 3.77 (P<0.001). With the usual method, the average acquisition time was 259seconds, compared to 69seconds with the Pixacare application, saving 3minutes and 10seconds per patient. CONCLUSION: The Pixacare software suite saves the surgeon significant time while ensuring appropriate data security. This study does not take into account the additional time saved by organising medical meetings, the benefits of sharing photographs between healthcare professionals and the efficiency of secure messaging.


Assuntos
Segurança Computacional , Aplicativos Móveis , Humanos , Fotografação , Estudos Prospectivos , Smartphone
3.
Br Poult Sci ; 57(4): 531-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27058041

RESUMO

Milanino is a heavy Italian chicken breed included in a conservation project of the University of Milan and is an important genetic resource for alternative production systems. This research was aimed to study the effect of the dietary protein concentration on growth, slaughter performance and meat composition in free-range reared Milanino chickens. A total of 120 Milanino chickens were fed on different protein concentrations (HP = 20% CP and LP = 16% CP), reared according to a free-range system and slaughtered at 150 and 180 d of age. Growth, slaughter performance and meat (breast and thigh) composition were recorded. The protein concentration of the diet did not affect the overall Milanino mean body weight recorded in the straight-run group in the whole rearing period. However, the growth rate within sex was significantly different between the dietary treatments: heavier females were found in the HP group from 125 d onwards, while no differences were recorded in male body weights. The protein concentration of the diet did not affect carcass weight data or meat composition. The present results suggest the use of a low-protein diet for rearing straight-run Milanino chickens for long rearing periods. However, in females, a high-protein diet is recommended from 125 d of age onwards.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Dieta com Restrição de Proteínas/veterinária , Proteínas Alimentares/metabolismo , Carne/normas , Ração Animal/análise , Animais , Composição Corporal , Galinhas/crescimento & desenvolvimento , Proteínas Alimentares/administração & dosagem , Feminino , Masculino , Carne/análise , Distribuição Aleatória
4.
J Virol Methods ; 149(2): 217-25, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18355929

RESUMO

A duplex real-time quantitative PCR (qPCR) method for the simultaneous detection of porcine circovirus type 2 (PCV2) and an exogenous internal positive control (IPC) in porcine semen samples was developed. The IPC was included to monitor DNA extraction and PCR inhibition and consisted of a mutated PCV2 plasmid clone which differed from the target PCV2 in the probe binding region and thus was detected by the use of a second probe with different end-labeling. The sensitivity, specificity and repeatability of the assay were validated by testing semen samples from 12 boars inoculated experimentally with PCV2, 10 boars infected naturally with PCV2, and 3 PCV2 negative control boars. The duplex qPCR assay was found to be more sensitive, specific, rapid, and repeatable than nested PCR (nPCR) methods for the detection of PCV2 DNA in semen. Analysis of separated semen fractions by the duplex qPCR assay showed PCV2 DNA to be present mainly in the cell fraction as opposed to the seminal plasma fraction which is in contrast to previous reports. The duplex qPCR assay was found to be a valuable tool for accurate and quantitative detection of PCV2 DNA in boar semen.


Assuntos
Infecções por Circoviridae/diagnóstico , Circovirus/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Sêmen/virologia , Animais , Primers do DNA/genética , Masculino , Plasmídeos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/virologia
5.
Poult Sci ; 97(4): 1148-1154, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29370417

RESUMO

The study aimed to characterize meat quality traits of Milanino chickens reared according to a specific free-range farming program. A total of 120 birds was reared straight-run in outdoor pens (8 m2/bird) from 35 d of life and fed ad libitum a low (16%) protein diet. At 180 d of age, 20 birds (10 birds/sex) were slaughtered, and carcass weight data were recorded. After processing, carcasses were refrigerated at 4°C for 24 hours. Then, the right breast and thigh with skin were collected and color parameters, pH, water-holding capacity (WHC), and chemical composition were determined. The left breast and thigh were stored at -20°C until cooking loss and tenderness evaluation. Milanino was confirmed to be a heavy breed with a sexual dimorphism in relation to adult body weight. A high general carcass yield was recorded. Milanino meat was characterized by high protein and low fat contents compared with the standard broiler meat. Differences in meat composition were recorded according to the sex: females presented higher values of dry matter (breast and thigh), protein (breast), and fat (breast and thigh) contents. The meat with skin presented an intense luminosity, and this trait was higher in the females. The muscle color was characterized by high redness and yellowness indices with differences according to the sex: Higher yellowness index was observed in female carcasses, while higher redness index was detected in male breast samples. The pH muscle values were similar to those reported in other autochthonous breeds. WHC values did not show variation between sexes. In contrast, cooking loss values recorded in thigh samples were lower in males compared to females. The degree of tenderness of Milanino meat was not affected by the sex. However, the potential loss of water and the toughness in Milanino meat were low compared to other local chicken breed meat. The present results support the breeding of Milanino chickens for meat production according to its specific straight-run free-range system.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Abrigo para Animais , Carne/análise , Animais , Composição Corporal , Culinária , Feminino , Itália , Masculino , Fatores Sexuais
6.
Anim Reprod Sci ; 190: 94-101, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29397251

RESUMO

The processing of ejaculates is a fundamental step for the fertilizing capacity of boar spermatozoa. The aim of the present study was to identify factors that affect quality of boar semen doses. The production process during 1 day of semen processing in 26 European boar studs was monitored. In each boar stud, nine to 19 randomly selected ejaculates from 372 Pietrain boars were analyzed for sperm motility, acrosome and plasma membrane integrity, mitochondrial activity and thermo-resistance (TRT). Each ejaculate was monitored for production time and temperature for each step in semen processing using the special programmed software SEQU (version 1.7, Minitüb, Tiefenbach, Germany). The dilution of ejaculates with a short-term extender was completed in one step in 10 AI centers (n = 135 ejaculates), in two steps in 11 AI centers (n = 158 ejaculates) and in three steps in five AI centers (n = 79 ejaculates). Results indicated there was a greater semen quality with one-step isothermal dilution compared with the multi-step dilution of AI semen doses (total motility TRT d7: 71.1 ±â€¯19.2%, 64.6 ±â€¯20.0%, 47.1 ±â€¯27.1%; one-step compared with two-step compared with the three-step dilution; P < .05). There was a marked advantage when using the one-step isothermal dilution regarding time management, preservation suitability, stability and stress resistance. One-step dilution caused significant lower holding times of raw ejaculates and reduced the possible risk of making mistakes due to a lower number of processing steps. These results lead to refined recommendations for boar semen processing.


Assuntos
Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Manejo de Espécimes/veterinária , Suínos/fisiologia , Animais , Masculino , Sêmen , Preservação do Sêmen/métodos , Manejo de Espécimes/métodos , Motilidade dos Espermatozoides , Espermatozoides , Temperatura , Fatores de Tempo
7.
Theriogenology ; 85(1): 21-6, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26525397

RESUMO

Bacteriospermia is a documented risk to reproductive performance when using extended boar semen for artificial insemination. A substantial list of bacteria have been recovered from boar semen attributed to fecal, preputial, skin, and hair microorganisms, with these and other environmental bacteria from processing areas identified in doses prepared for artificial insemination. Gram-negative bacteria are most commonly recovered from extended doses, including both Enterobacteriaceae and environmental contaminants, such as those that inhabit water purification systems. The method of processing, distributing, and storing fresh liquid boar semen before insemination plays a role in bacterial growth dynamics and the degree to which the bacteria may damage the sperm or affect the sow. Not all bacterial isolates or contamination levels have the same impact on sperm, with multiple factors governing if and when storage longevity will be reduced through sperm-to-sperm agglutination, impaired motility, acrosome disruption, or loss of membrane viability. Suboptimal reproductive performance can occur because of reduced fertilizing capacity of the sperm or induction of a uterine environment hostile to sperm and/or embryonic survival. Effective bacterial control strategies are necessary to minimize the risk of bacteria contaminating extended semen doses, including monitoring programs designed for quick detection and intervention, should the need arise.


Assuntos
Reprodução/fisiologia , Preservação do Sêmen/veterinária , Sêmen/microbiologia , Espermatozoides/fisiologia , Suínos/fisiologia , Animais , Masculino
8.
Gene ; 109(1): 89-97, 1991 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-1756986

RESUMO

The XYL1 gene of the yeast Pichia stipitis has been isolated from a genomic library using a specific cDNA probe, and its nucleotide (nt) sequence has been determined. In the 5' noncoding region of the P. stipitis XYL1 gene a TATAAA element (known to be necessary for transcription initiation in most yeast genes) is found at nt -81, and two CCAAT recognition motifs (often referred to as the CCAAT box) are present at nt -146 and -106. The XYL1 encodes a polypeptide of 35,927 Da that constitutes a NADH/NADPH-dependent xylose reductase (XR). The enzyme is part of the xylose-xylulose pathway that is absent or only weakly expressed in Saccharomyces cerevisiae. Extensive homology is found to the N terminus of the XR of Pachysolen tannophilus and Candida shehatae. None of the known cofactor binding domains found in many NAD-dependent dehydrogenases are present in the protein. Transformants of S. cerevisiae containing XYL1 of P. stipitis synthesize an active XR. Fusion of XYL1 with the prokaryotic tac promoter leads to a gene that can be expressed in S. cerevisiae and Escherichia coli.


Assuntos
Aldeído Redutase/genética , Expressão Gênica , Pichia/genética , Saccharomyces cerevisiae/genética , Aldeído Redutase/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Candida/genética , Clonagem Molecular , DNA de Cadeia Simples , Biblioteca Gênica , Dados de Sequência Molecular , NADP/metabolismo , Pichia/metabolismo , Proteínas Recombinantes , Sequências Reguladoras de Ácido Nucleico , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência do Ácido Nucleico , Transformação Genética
9.
Theriogenology ; 52(3): 365-76, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10734372

RESUMO

Extending the raw ejaculate prior to artificial insemination (AI) is beneficial, in part, due to the increased number of females that are bred from an ejaculate, along with prolonged shelf life of the semen. The objective of this study was to examine the affects of storage time on the fecundity of porcine semen diluted in 2 semen extenders, Androhep and X-CELL. A completely randomized design with a factorial arrangement of treatments was utilized in which 429 high quality, gel-free ejaculates from 48 boars were used in a timed, double insemination of 1,431 first-service gilts. The gilts were divided into groups and inseminated with semen stored in Androhep or X-CELL for 2 to 3 d, 3 to 4 d, 4 to 5 d, or 5 to 6 d prior to use (day of collection = Day 0). Sperm age was identical, and both extenders were used concurrently each day of the trial. Farrowing rate and litter size data were recorded. Farrowing rates did not differ between extenders through Days 4 to 5 of storage. Gilts inseminated with Androhep diluted stored semen showed a decrease (P < 0.001) in farrowing rate compared with those inseminated with semen extended in X-CELL stored for 5 to 6 d. Mean litter sizes did not differ between extenders through Days 2 to 3 of storage. Compared with the X-CELL extended semen, gilts inseminated with Androhep extended semen produced smaller litters when semen was stored for 4 to 5 d (P < 0.05). Within the Androhep treatment, smaller mean litter sizes (P < 0.05) were evident when the semen was stored for 3 to 4 and 4 to 5 d. No differences were detected in litter size or farrowing rate for gilts bred with semen stored for 2 to 6 d in the X-CELL extender (P > 0.1). The results of this study indicate that extender type influences the fertility potential of fresh porcine semen stored for 2 to 6 d. For optimal fecundity in gilts, semen extended with Androhep extender should be used for AI within 3 d. The X-CELL extended semen can be used for up to 6 d without significant decrease in litter size or farrowing rate. These recommendations are dependent upon using high quality semen that is properly handled from collection through insemination.


Assuntos
Fertilidade , Inseminação Artificial/veterinária , Prenhez , Preservação do Sêmen/veterinária , Sêmen/fisiologia , Animais , Feminino , Inseminação Artificial/métodos , Tamanho da Ninhada de Vivíparos , Masculino , Gravidez , Preservação do Sêmen/métodos , Soluções , Suínos , Fatores de Tempo
10.
Theriogenology ; 61(4): 691-703, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14698058

RESUMO

Morphologic assessment of spermatozoa is an integral component in the analysis of semen. Whether a technician rapidly screening semen quality at a commercial stud, a veterinarian performing breeding soundness examinations, a clinician at a reference andrology laboratory providing auditing or diagnostic services, or a researcher evaluating morphology as a part of a fertility study, it is important to make an informed decision regarding the number of spermatozoa to include in the morphology assessment. Application of basic statistical principles such as the nature of proportions, level of confidence in an observed value, and the interaction of sample size with precision, can and should be used in the decision process. This paper outlines in detail the application of these statistical principles in relation to the morphologic assessment of spermatozoa. Guidelines on how these principles can be utilized in practical situations are discussed. Additionally, methodologies for comparison of results within and between laboratories (an area easily prone to misinterpretation) are reviewed. It is hoped that through the use of these fundamental statistical principles, this paper will bring clarity and delineation to the science of quantifying the morphology of spermatozoa.


Assuntos
Sêmen/fisiologia , Contagem de Espermatozoides , Espermatozoides/citologia , Animais , Intervalos de Confiança , Laboratórios , Masculino , Tamanho da Amostra , Sensibilidade e Especificidade , Espermatozoides/anormalidades
11.
Theriogenology ; 50(4): 535-43, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10732145

RESUMO

Irreversible damage caused by cold shock has been assumed to occur when boar semen is exposed to temperatures below 15 degrees C. Identification of the lower critical temperature at which extended boar semen undergoes cold shock, however, has yet to be defined. The aims of this study were to 1) identify the cold-shock critical temperature and time on extended boar semen as assessed by sperm motility and morphology, and 2) determine the effects on fertility of using extended porcine semen exposed to this critical temperature and time. For Objective 1, ejaculates from 18 boars were collected, analyzed and extended in Androhep to 50 x 10(6) sperm/mL. Doses (4 x 10(9) sperm) from each ejaculate were exposed to 5 storage temperatures (8, 10, 12, 14 and 17 degrees C). Sperm motility and morphology (including acrosomes) were assessed following collection and at 12-h intervals for 48-h. Decreases in sperm motility occurred within the first 12-h at all temperatures. Sample motility dropped below 70% within 12-h in the 8 degrees C group and by 48-h in the 10 degrees C group. Sample motility was > 75% in the 12, 14 and 17 degrees C (control) groups throughout the trial. The percentage of morphologically abnormal sperm cells, including acrosomes, did not change within or between treatment groups over the 48-h storage period. In Objective 2, boar ejaculates (n = 9) were handled as in the first objective and were equally divided into treated (12 degrees C for < or = 60-h) and control (17 degrees C for < or = 60-h) groups. Using a timed, double insemination technique, 135 sows were bred by AI using either 12 degrees C (n = 74) or 17 degrees C (n = 61) extended, stored semen. No differences were observed in the farrowing rate (93 vs 95%), total offspring born (11.58 vs 11.61) or number live born (10.68 vs 10.63) between 12 and 17 degrees C groups, respectively. The results demonstrate that acceptable fertility can be obtained with Androhep extended boar semen exposed to temperatures as low as 12 degrees C for up to 60-h, and that cold shock appears to occur in vitro when extended boar semen is exposed to storage temperatures below 12 degrees C.


Assuntos
Temperatura Baixa , Sêmen/fisiologia , Espermatozoides/fisiologia , Suínos/fisiologia , Acrossomo/fisiologia , Acrossomo/ultraestrutura , Animais , Feminino , Fertilização , Inseminação Artificial/veterinária , Masculino , Motilidade dos Espermatozoides , Espermatozoides/anormalidades , Espermatozoides/ultraestrutura
12.
Theriogenology ; 53(5): 1167-76, 2000 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10798493

RESUMO

Field investigations (n=23) were made over a 3-yr period at North American boar studs and farms in which the primary complaint was sperm agglutination in association with decreased sperm longevity of extended semen, and increased regular returns to estrus and/or vaginal discharges across parity. Microscopic examination of extended semen from these units revealed depressed gross motility (usually <30%), sperm agglutination, and sperm cell death occurring within 2 d of semen collection and processing regardless of the semen extender used. The extended semen exhibited a high number of induced acrosome abnormalities (>20%). Sample pH was acidic (5.7 to 6.4) in 93% of the submitted samples. Aerobic culture yielded a variety of bacteria from different genera. A single bacterial contaminant was obtained from 66% of the submitted samples (n=37 doses); 34% contained 2 or more different bacterial genera. The most frequently isolated contaminant bacteria from porcine extended semen were Alcaligenes xylosoxydans (n=3), Burkholderia cepacia (n=6), Enterobacter cloacae (n=6), Escherichia coli (n=6), Serratia marcescens (n=5), and Stenotrophomonas [Xanthomonas] maltophilia (n=6); these 6 bacteria accounted for 71% of all contaminated samples, and were spermicidal when re-inoculated and incubated in fresh, high quality extended semen. All contaminant bacteria were found to be resistant to the aminoglycoside gentamicin, a common preservative antibiotic used in commercial porcine semen extenders. Eleven genera were spermicidal in conjunction with an acidic environment, while 2 strains (E. coli, S. maltophilia) were spermicidal without this characteristic acidic environment. Bacteria originated from multiple sources at the stud/farm, and were of animal and nonanimal origin. A minimum contamination technique (MCT) protocol was developed to standardize hygiene and sanitation. This protocol focused on MCT's during boar preparation, semen collection, semen processing and laboratory sanitation. Implementation of the MCT, in addition to specific recommendations in stud management, resulted in the control of bacterial contamination in the extended semen.


Assuntos
Cruzamento/métodos , Sêmen/microbiologia , Suínos/microbiologia , Alcaligenes/isolamento & purificação , Animais , Burkholderia cepacia/isolamento & purificação , Enterobacter cloacae/isolamento & purificação , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Humanos , Serratia marcescens/isolamento & purificação , Pele/microbiologia , Microbiologia da Água , Xanthomonas/isolamento & purificação
13.
Soz Praventivmed ; 31(6): 290-3, 1986.
Artigo em Alemão | MEDLINE | ID: mdl-3811603

RESUMO

Mentally retarded adults frequently live in psychatric hospitals because no other place could be found for them. Analysis of data of all mentally handicapped residents in psychatric clinics and special homes in two swiss cantons showed that in no case permanent hospitalisation was justified by severity of additional handicaps nor by behavioural disturbances. The main reason for permanent hospitalisation is practically always the lack of other possibilities of permanent care.


Assuntos
Hospitais Psiquiátricos , Institucionalização , Deficiência Intelectual , Instituições Residenciais , Adulto , Humanos , Suíça
14.
J Dent Educ ; 47(10): 676-80, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6578248

RESUMO

Approximately 40 percent of the data-based articles reported in the Journal of Dental Education in the last five years have used survey research procedures. This study examines the use of one type of survey procedure, mailed questionnaires, in research on dental education. Specifically, the discussion identifies several factors that dental education researchers should consider when reporting mailed questionnaire research to journal editors. These factors are discussed using examples of adequate and inadequate procedures reported in the method sections of studies in the Journal of Dental Education in the last five years.


Assuntos
Coleta de Dados/métodos , Educação em Odontologia , Humanos , Pesquisa , Projetos de Pesquisa , Inquéritos e Questionários
15.
Anesth Prog ; 31(3): 130-2, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6332558

RESUMO

This study investigated the frequency of hematoma formation subsequent to injection of dental local anesthetics in 4,134 children, 3 to 13 years of age. Hematoma formation occurred following 0.1% of the injections, all being buccal infiltrations of maxillary molars. This represents a 0.4% incidence of hematoma formation subsequent to this injection. There was no age specificity in hematoma formation, occurring in one 5 year old, one 7 year old, one 8 year old, one 10 year old, and one 11 year old.


Assuntos
Anestesia Dentária/efeitos adversos , Anestesia Local/efeitos adversos , Hematoma/epidemiologia , Hemorragia Bucal/epidemiologia , Adolescente , Criança , Pré-Escolar , Humanos , Injeções/efeitos adversos
16.
J Clin Pediatr Dent ; 17(2): 95-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8466847

RESUMO

A case is presented of a 12-year-old, black male, who had a full permanent dentition except for retaining the two maxillary primary central incisors. A radiographic examination revealed the presence of two supernumerary teeth interfering with the eruption of the permanent central incisors. Space was orthodontically created for the permanent central incisors, the primary central incisors and supernumerary teeth were removed, and the permanent central incisors were orthodontically brought into proper alignment.


Assuntos
Ortodontia Corretiva/métodos , Dente Supranumerário/complicações , Dente não Erupcionado/etiologia , Criança , Humanos , Incisivo/fisiopatologia , Masculino , Maxila , Erupção Dentária , Extração Dentária , Dente Supranumerário/cirurgia
17.
Mol Ecol Resour ; 12(6): 1048-57, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22925691

RESUMO

Determining genetic variation at the DNA level within and between natural populations is important for understanding the role of natural selection on phenotypic traits, but many techniques of screening for genetic variation are either cost intensive, not sensitive enough or too labour- and time-consuming. Here, we demonstrate high-resolution melting analysis (HRMA) as a cost-effective and powerful tool for screening variable target genes in natural populations. HRMA is based on monitoring the melting of PCR amplicons. Owing to saturating concentrations of a dye that binds at high concentrations to double-stranded DNA, it is possible to genotype high numbers of samples rapidly and accurately. We analysed digestive trypsins of two Daphnia magna populations as an application example for HRMA. One population originated from a pond containing toxic cyanobacteria that possibly produce protease inhibitors and the other from a pond without such cyanobacteria. The hypothesis was that D. magna clones from ponds with cyanobacteria have undergone selection by these inhibitors, which has led to different trypsin alleles. We first sequenced pooled genomic PCR products of trypsins from both populations to identify variable DNA sequences of active trypsins. Second, we screened variable DNA sequences of each D. magna clone from both populations for single nucleotide polymorphisms via HRMA. The HRMA results revealed that both populations exhibited phenotypic differences in the analysed trypsins. Our results indicate that HRMA is a powerful genotyping tool for studying the variation of target genes in response to selection within and between natural Daphnia populations.


Assuntos
Biota , DNA/genética , Daphnia/classificação , Daphnia/genética , Variação Genética , Biologia Molecular/métodos , Temperatura de Transição , Alelos , Animais , Cianobactérias/crescimento & desenvolvimento , DNA/isolamento & purificação , Daphnia/enzimologia , Genótipo , Biologia Molecular/economia , Seleção Genética , Tripsina/genética
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