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1.
Zool J Linn Soc, zlac059, nov. 2022
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4704

ABSTRACT

Morphological stasis is generally associated with relative constancy in ecological pressures throughout time, producing strong stabilizing selection that retains similar shared morphology. Although climate and vegetation are commonly the main key factors driving diversity and phenotypic diversification in terrestrial vertebrates, fossorial organisms have their morphology mostly defined by their fossorial lifestyle. Among these secretive fossorial organisms, blind snakes of the South American genus Amerotyphlops are considered poorly studied when compared to other taxa. Here, we evaluate the cryptic diversity of Amerotyphlops using phylogenetic and multivariate approaches. We based our phylogenetic analysis on a molecular dataset composed of 12 gene fragments (eight nuclear and four mitochondrial) for 109 species of Typhlopidae. The multivariate analysis was implemented using 36 morphological variables for 377 specimens of Amerotyphlops. Additionally, we contrast our phylogenetic result with the morphological variation found in cranial, external and hemipenial traits. Our phylogenetic results recovered with strong support the following monophyletic groups within Amerotyphlops: (1) a clade formed by A. tasymicris and A. minuisquamus; (2) a clade composed of A. reticulatus; (3) a north-eastern Brazilian clade including A. yonenagae, A. arenensis, A. paucisquamus and A. amoipira; and (4) a clade composed of A. brongersmianus and a complex of cryptic species. Based on these results we describe four new species of Amerotyphlops from north-eastern and south-eastern Brazil, which can be distinguished from the morphologically similar species, A. brongersmianus and A. arenensis.

2.
Anat Rec (Hoboken) ; 304(10): 2183-2197, 2021 10.
Article in English | MEDLINE | ID: mdl-34101371

ABSTRACT

Since the rearrangement of all leptotyphlopid species previously known as "Leptotyphlops" in Adalsteinsson et al. (2009)'s paper, several taxa have remained untested regarding their generic identity and have been assigned to different genera based on phenotypic data or, in some cases, without any clear justification. Most of the difficulties in assigning some leptotyphlopid taxa are due to their conserved external morphology, summed with a relatively small number of available specimens, which complicate the recognition of a unique combination of characters for their reasonable generic allocation. On the other hand, recent osteological studies-especially those on the skull-provide relevant data combinations for species assignment and even for the recognition of new genera. In this work, we have attempted to determine the generic allocation of Epictia unicolor and Trilepida guayaquilensis-both species currently known only by their holotype-based on a detailed description of cranial and post-cranial osteology. We confirm the assignment of E. unicolor to the genus Epictia despite the divergent configuration of cephalic shields. Based mainly on data from the skull, suspensorium, and cervical vertebrae but supported by external morphology as well as a redescription of the holotype, we propose the assignment of Trilepida guayaquilensis to the genus Epictia. This study provides not only detailed data on the osteology of Epictia, but also a first approach to the putative combination of osteological characters for the genus.


Subject(s)
Osteology , Snakes , Animals
3.
Clin Physiol Funct Imaging ; 38(1): 17-24, 2018 Jan.
Article in English | MEDLINE | ID: mdl-27283375

ABSTRACT

PURPOSE: This study aimed to compare haemodynamic, rating of perceived exertion and blood lactate responses during resistance exercise with blood flow restriction (BFR) compared with traditional high-intensity resistance exercise in hypertensive older women. METHODS: Eighteen hypertensive women (age = 67·0 ± 1·7 years.) undertook three random sessions: (i) three sets; 10 repetitions; 20% of one repetition maximum (1RM) with BFR; (ii) three sets; 10 repetitions; 65% of 1RM; without BFR; and (iii) no-exercise with BFR. The exercise sessions were performed on knee extension equipment. RESULTS: Systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV) and cardiac output (CO) were significantly higher (P<0·05) in all sets of exercise sessions than the control. No statistically significant differences were detected between exercise sessions. However, SBP, DBP and systemic vascular resistance were higher (P<0·05) and SV and CO were lower (P<0·05) during the rest intervals in the session with BFR. The perceived exertion was significantly higher (P<0·01) in the 1st (4·8 ± 0·4 versus 3·1 ± 0·3), 2nd (7·3 ± 0·4 versus 5·7 ± 0·4) and 3rd sets (8·6 ± 0·5 versus 7·5 ± 0·4) of the traditional high-intensity resistance exercise compared with the exercise with BFR. Blood lactate was higher (P<0·05) in the traditional high-intensity resistance exercise (6·2 ± 0·7 mmol) than in the exercise with BFR (4·5 ± 0·4 mmol). CONCLUSION: In comparison with high-intensity resistance exercise, low-intensity resistance exercise with BFR can elicit: (i) same haemodynamic values during exercise; (ii) lower rating of perceived exertion; (iii) lower blood lactate; (iv) higher haemodynamic demand during the rest intervals.


Subject(s)
Hemodynamics , Hypertension/therapy , Ischemia , Lactic Acid/blood , Perception , Resistance Training/methods , Thigh/blood supply , Age Factors , Aged , Aging/blood , Biomarkers/blood , Cross-Over Studies , Female , Humans , Hypertension/blood , Hypertension/diagnosis , Hypertension/physiopathology , Regional Blood Flow , Resistance Training/adverse effects , Sex Factors , Time Factors , Treatment Outcome
4.
Zootaxa ; 4244(2): 246-260, 2017 Mar 19.
Article in English | MEDLINE | ID: mdl-28610123

ABSTRACT

We report on the morphological variation (meristic, morphometric, pholidosis, and color pattern characters) and sexual dimorphism of Trilepida macrolepis. We also took the opportunity to redescribe the holotype of Rena affinis in an effort to evaluate its taxonomic status. Based on the congruence of characters from external morphology, we transfer Stenostoma affine to the genus Trilepida. We also discuss the Andean specimens previously refereed to Trilepida affinis and Trilepida macrolepis and provide an identification key for the genus Trilepida.


Subject(s)
Snakes , Animals , Color , Sex Characteristics
5.
Zootaxa ; 4105(1): 45-64, 2016 Apr 19.
Article in English | MEDLINE | ID: mdl-27394764

ABSTRACT

The freshwater turtle Acanthochelys radiolata (Mikan, 1820) is endemic to the Atlantic Forest domain in Brazil and few studies have been done on the morphology, geographic variation and taxonomy of this species. In this paper we record the morphological variation, as well as sexual dimorphism and ontogenetic changes in A. radiolata throughout its distribution range. We analyzed 118 morphological characters from 41 specimens, both quantitative and qualitative, and performed statistical analyses to evaluate size and shape variation within our sample. Morphological analysis revealed that A. radiolata is a polymorphic species, especially regarding color and shape. Two color patterns were recognized for the carapace and three for the plastron. Diagnostic characteristics of the species, such as the rounded tubercles on the neck and the shallow dorsal sulcus between the 2nd and 4th vertebral scutes, varied considerably. Acanthochelys radiolata also showed a high level of ontogenetic variation characterized by a change on the color pattern of plastron and limbs starting from the 4th month of life. Sexual size dimorphism was observed for the first time on nine morphometric variables and females showed larger sizes than males. Based on these results we conclude that A. radiolata represents one single polymorphic species distributed in the lowlands of the Brazilian Atlantic Forest from the state of Alagoas to the state of Rio de Janeiro and the south of Minas Gerais state.


Subject(s)
Turtles/anatomy & histology , Turtles/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Brazil , Female , Male , Organ Size , Sex Characteristics , Turtles/growth & development , Turtles/physiology , Wetlands
6.
Clin Physiol Funct Imaging ; 36(5): 407-13, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26095652

ABSTRACT

PURPOSE: This study aimed to compare haemodynamic responses during resistance exercise with blood flow restriction (BFR) in hypertensive women. METHODS: Twelve hypertensive women undertook three random experimental sessions in the leg-press exercise: (i) Three sets, eight repetitions, 20% of one-repetition maximum (1 RM), with BFR; (ii) Three sets, 15 repetitions, 65% of 1 RM, without BFR; and (iii) three sets, 15 repetitions, 20% of 1 RM, without BFR. The BFR was performed using two sphygmomanometers adjusted to fit both thighs. Systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO) and systemic vascular resistance (SVR) were measured on a beat-to-beat continuous basis. RESULTS: When compared to the 20% without BFR, the session with BFR presented increased values in all sets for the variables SBP, DBP, CO and SVR, and in the 2nd and 3rd sets for HR. The session with BFR also presented increased values compared to the 65% of 1 RM in the 2nd and 3rd sets for the variables SBP, DBP and HR and in all sets for the variables CO and SVR. CONCLUSION: Low-intensity resistance exercise with BFR can initiate higher haemodynamic and cardiovascular values than traditional high-intensity resistance exercises in hypertensive women.


Subject(s)
Hemodynamics , Resistance Training/methods , Blood Pressure , Cardiac Output , Female , Heart Rate , Humans , Hypertension/diagnosis , Random Allocation , Regional Blood Flow , Time Factors , Tourniquets , Vascular Resistance
7.
Anat Rec (Hoboken) ; 298(10): 1722-47, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26119424

ABSTRACT

Morphological and anatomical studies on the Leptotyphlopidae have increased in the past 10 years, providing important data on the systematics of this group, mainly focused on the skull and lower jaw morphology. However, most studies are based on a single specimen, rarely combining more than one single method of assessing morphological information. Therefore, several data on postcranial morphology, sexual dimorphism, and ontogenetic and intraspecific variation of leptotyphlopids remain poorly understood. Herein, we provide a detailed description of the cranial and postcranial skeleton of Trilepida salgueiroi based on more than 20 specimens (including males, females and juveniles), as well as a description of osteology and cartilaginous elements through the use of combined methodologies such as X-ray scanning, high resolution CT-scanning, and clearing and staining of articulated and disarticulated specimens. We also provide data on the presence/absence of dimorphic and intraspecific variation of the observed characters. The presence of a statolithic mass in the cavum vestibuli differs from the pattern found in other scolecophidians. A correlation of dorsal vertebrae with ventral and subcaudal scales was found (1:1), as well as total number of vertebrae with middorsal scales (1:1), thoracolumbar vertebrae and ventral scales (1:1), and a higher number of caudal vertebra with subcaudal scales (1.23:1). Intraspecific variation was found in several elements of the skull, lower jaw, pelvic girdle and vertebral number, but no evidence of sexual dimorphism was found in any of the species characters analysed. The homologies of several elements are discussed, although still remaining poorly understood and unknown.


Subject(s)
Cartilage/anatomy & histology , Skull/anatomy & histology , Animals , Bone and Bones/anatomy & histology , Female , Male , Snakes/anatomy & histology
8.
Arq. bras. endocrinol. metab ; 48(3): 337-344, jun. 2004. ilus
Article in Portuguese | LILACS | ID: lil-365148

ABSTRACT

As UCPs constituem um subgrupo das proteínas carreadoras mitocondriais que estão localizadas na membrana mitocondrial interna. Por meio da dissipação do gradiente de próton, elas desacoplam a fosforilação oxidativa e convertem combustível em calor. Foram identificadas quatro isoformas da UCP. A UCP-1 foi a primeira a ser descoberta, sendo encontrada exclusivamente no tecido adiposo marrom, a UCP-2 é encontrada em vários tecidos, a UCP-3 encontra-se no músculo esquelético em humanos e tecido adiposo marrom e músculo esquelético em roedores, enquanto a UCP-4 é expressa no cérebro. A expressão da UCP-3 no músculo esquelético e no tecido adiposo marrom pode fazer destes tecidos importantes mediadores da termogênese adaptativa. No entanto, o papel da UCP-3 quanto ao gasto de energia e como causa da obesidade ainda não passa de uma hipótese. Há evidências de que a UCP-3 seja regulada pelos substratos energéticos, tais como ácidos graxos e glicose que, ao entrarem no músculo, provocam aumento da UCP-3 e aumento no gasto de energia. Nosso objetivo nesta revisão foi descrever e discutir as informações disponíveis sobre a regulação da UCP-3, e sua possível relação com o controle do peso corporal.


Subject(s)
Animals , Humans , Body Weight/genetics , Carrier Proteins/genetics , Gene Expression Regulation , Muscle, Skeletal/metabolism , Adipose Tissue, Brown/physiology , Ion Channels , Mitochondrial Proteins
9.
Arq Bras Endocrinol Metabol ; 48(3): 337-44, 2004 Jun.
Article in Portuguese | MEDLINE | ID: mdl-15640895

ABSTRACT

Uncoupling proteins constitute a subgroup of mitochondrial carrier proteins that are located in the inner mitochondrial membrane. By dissipating proton gradients, they act to uncouple respiration from oxidative phosphorylation and convert fuel to heat. Four homologous UCP isoforms have been identified. UCP-1, the first UCP to be described, is found exclusively in brown adipose tissue, UCP-2 in several tissues, UCP-3 in human skeletal muscle and rat brown adipose tissue and skeletal muscle, whereas UCP-4 is expressed in the brain. Expression of UCP-3 in the skeletal muscle and the brown adipose tissue may place these tissues as important mediators for adaptative thermogenesis. However, the role of UCP-3 in energy expenditure and as a cause of obesity has been controversial. There are evidences that UCP-3 can be regulated by energy substrates as fatty acids and glucose, by entering the muscle and stimulating UCP-3 to increase energy expenditure. Our aim in this review was to describe and discuss the available information on UCP-3 regulation and its possible relation with body weight control.


Subject(s)
Body Weight/genetics , Carrier Proteins/genetics , Gene Expression Regulation , Muscle, Skeletal/metabolism , Adipose Tissue, Brown/physiology , Animals , Humans , Ion Channels , Mitochondrial Proteins , Uncoupling Protein 3
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