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1.
Arch Dermatol Res ; 316(5): 144, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695894

RESUMO

Hand infection is a rare complication in patients with diabetes. Its clinical outcomes depend on the severity of hand infection caused by bacteria, but the difference in bacterial species in the regional disparity is unknown. The purpose of this study was to explore the influence of tropical and nontropical regions on bacterial species and clinical outcomes for diabetic hand. A systematic literature review was conducted using PubMed, EMBASE, Web of Science, and Google Scholar. Moreover, the bacterial species and clinical outcomes were analyzed with respect to multicenter wound care in China (nontropical regions). Both mixed bacteria (31.2% vs. 16.6%, p = 0.014) and fungi (7.5% vs. 0.8%, p = 0.017) in the nontropical region were significantly more prevalent than those in the tropical region. Staphylococcus and Streptococcus spp. were dominant in gram-positive bacteria, and Klebsiella, Escherichia coli, Proteus and Pseudomonas in gram-negative bacteria occupied the next majority in the two regions. The rate of surgical treatment in the patients was 31.2% in the nontropical region, which was significantly higher than the 11.4% in the tropical region (p = 0.001). Although the overall mortality was not significantly different, there was a tendency to be increased in tropical regions (6.3%) compared with nontropical regions (0.9%). However, amputation (32.9% vs. 31.3%, p = 0.762) and disability (6.3% vs. 12.2%, p = 0.138) were not significantly different between the two regions. Similar numbers of cases were reported, and the most common bacteria were similar in tropical and nontropical regions in patients with diabetic hand. There were more species of bacteria in the nontropical region, and their distribution was basically similar, except for fungi, which had differences between the two regions. The present study also showed that surgical treatment and mortality were inversely correlated because delays in debridement and surgery can deteriorate deep infections, eventually leading to amputation and even death.


Assuntos
Clima Tropical , Humanos , Complicações do Diabetes/microbiologia , Complicações do Diabetes/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/terapia , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/mortalidade , Mãos/microbiologia , China/epidemiologia , Bactérias/isolamento & purificação , Bactérias/classificação , Resultado do Tratamento , Amputação Cirúrgica/estatística & dados numéricos
2.
J Hand Surg Asian Pac Vol ; 29(2): 96-103, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494167

RESUMO

Background: Various studies have examined occlusive dressings in fingertip amputations and reported good outcomes. Occlusive dressing preserves appropriate pH, cell accumulation and moisture for healing, thereby limiting scar formation and deformity. To our knowledge, no study was performed in tropical Asia. This study aims to demonstrate the viability of healing fingertip amputations through secondary intention using an effective dressing technique, even in warm tropical climates. Methods: All patients who presented to our institution with fingertip amputations from 1 July 2020 to 31 July 2022 were analysed retrospectively. Seventeen patients (15 male, 2 female) of mean age 37.2 ± 9.4 years old with 18 injured digits were retrospectively analysed. Twelve (66.7%) were Allen Type III injuries, and one patient required distal phalangeal K-wire fixation. During the patient's final review, static 2-point discrimination, pulp sensation, fingertip contour and nail deformities alongside the last measured range of motion (ROM) of the injured finger was recorded. Treatment duration and days of leave taken were also summed and assessed. Results: Patients were dressed with semi-occlusive dressing for an average of 20.1 ± 6.83 days. The average total duration of dressing is 36.78 ± 18.88 days over an average of 7.18 ± 4.03 dressing visits. Mean duration of follow-up was 108 ± 63.46 days. Good outcome measures in sensation, pulp contour, nail deformity and ROM similar to existing literature were reported. Conclusions: Occlusive dressing remains a viable and feasible treatment option for fingertip amputation even in a tropical climate. While this simple treatment method may require more effort from patient, wound healing was attained after 36.8 ± 18.9 days of dressing. Level of Evidence: Level IV (Therapeutic).


Assuntos
Traumatismos dos Dedos , Doenças da Unha , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Clima Tropical , Estudos Retrospectivos , Intenção , Traumatismos dos Dedos/cirurgia , Cicatrização
3.
Pediatr Exerc Sci ; 36(1): 8-14, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37604485

RESUMO

PURPOSE: We examined fluid intake, the relation between body mass (BM) loss and performance, and core temperature in young triathletes during a competition in tropical climate. METHODS: Fluid intake and pre and post BM were measured in 35 adolescent athletes, and core temperature was measured in one female and one male. RESULTS: Mean urine specific gravity (1.024 [0.007]) indicated that athletes were in suboptimal state of hydration upon waking. Race time was 73.2 (8.0) minutes. BM decreased by 0.6 (0.3) kg (P < .05). Fluid intake (528.5 [221.6] mL) replaced 47% of the fluid loss (1184.9 [256.4] mL) and was higher during run (11.5 [6.6] mL·min-1) compared to bike (7.3 [3.1] mL·min-1), P < .01. Loss in BM was ≥1.0% in 66% and ≥1.5% in 29% of the athletes. Males showed a moderate association between percentage loss in BM and finishing time (r = -.52), higher sweat rates (1.0 [0.3] L·h-1), and faster times (69.4 [7.5] min; P < .05). Core temperature rose to 40.1 °C in the female and 39.6 °C in the male. CONCLUSION: Young triathletes competing in a hot/humid climate became mildly to moderately dehydrated and hyperthermic even when water and sports drinks were available but did not show symptoms of heat illness.


Assuntos
Esportes , Clima Tropical , Adolescente , Humanos , Masculino , Feminino , Desidratação , Ingestão de Líquidos , Sudorese , Equilíbrio Hidroeletrolítico
4.
Exp Appl Acarol ; 91(4): 541-559, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37884811

RESUMO

Varroa destructor is a damaging mite of Western honey bees (Apis mellifera). Genetic variability of the mite in different regions of the world could be related to the movement of infested bees or other factors, such as climate. In this study, V. destructor samples were collected from tropical and temperate climate regions of Mexico, and a humid continental climate region of Canada. COX-1 AFLPs showed that all the mites were the Korean haplotype. Four microsatellites revealed nine haplogroups from the continental climate region of Canada, compared to three haplogroups from the tropical and temperate climate regions of Mexico. CytII-ATP sequences showed seven haplogroups from the humid continental climate region vs. two haplogroups from the temperate region and one haplogroup from the tropical region. CytB sequences revealed seven haplogroups from Canada vs. three from Mexico. A comparison of the cytB sequences of the samples from Canada and Mexico to those from a worldwide collection showed that one sequence, designated the cytB1 type, predominated, comprising 57% of the 86 sequences; it clustered with similar sequences that comprised 80% of the sequences, designated family A. CytB1 was predominant in Mexico, but not in Canada. The other 20% of sequences were in families B and C, and all those samples originated from East and Southeast Asia. The microsatellite, cytII-ATP, and cytB markers, all showed higher variability in mites collected in Canada than in Mexico, which could be related to the cooler climate or an earlier invasion and/or multiple mite invasions in Canada.


Assuntos
Varroidae , Humanos , Animais , Abelhas/genética , Varroidae/genética , México , Clima Tropical , Canadá , Trifosfato de Adenosina
5.
Trop Anim Health Prod ; 55(4): 241, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328676

RESUMO

A feeding trial was conducted for a period of 60 days during extreme summer months to observe the effect of supplementation of Moringa oleifera leaves containing concentrate pellets on nutrient utilization, antioxidant status, and reproductive performance in Avishaan ewes reared under semi-arid condition. Forty adult non-pregnant cyclic ewes (2-3 years, 31.8 ± 0.81 kg body weight) were selected and randomly allocated into 2 groups of 20 animals each, viz., G-I (control) and G-II (treatment). The ewes were grazed on natural pasture for 8 h, offered ad libitum Cenchrus ciliaris hay after grazing and concentrate pellets @ 300 g/animal/day. The ewes in G-I were offered conventional concentrate pellets, whereas G-II ewes were offered concentrate pellets containing 15% Moringa leaves. The mean temperature humidity index during the period of study was 27.5 ± 0.3 and 34.6 ± 0.4 at 0700 h and 1400 h, respectively, indicating severe heat stress. Nutrient intake and utilization were comparable between the two groups. The antioxidant status was higher in G-II ewes as the values of catalase, superoxide dismutase, and total antioxidant capacity were higher (P < 0.05) in G-II ewes compared to G-I. The conception rate was higher (100%) in G-II ewes than G-I ewes (70%). Multiple birth percentage was 77.8% in G-II ewes, and it was comparable with the herd average of Avishaan (74.7%). However, ewes in G-I group exhibited a marked decline in multiple birth percentage (28.6%) than the normal herd average. Hence, it can be concluded that inclusion of Moringa oleifera leaves in feeding of prolific Avishaan ewes improved their antioxidant status resulting in optimum reproductive performance during stressful summer months.


Assuntos
Antioxidantes , Moringa oleifera , Ovinos , Animais , Feminino , Clima Tropical , Nutrientes , Suplementos Nutricionais/análise , Folhas de Planta
6.
Nat Prod Rep ; 40(7): 1181-1197, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37194649

RESUMO

Covering up to early 2023The present review summarizes recent accomplishments made as part of a multidisciplinary, multi-institutional anticancer drug discovery project, wherein samples comprising higher plants were collected primarily from Southeast Asia, and also from Central America, and the West Indies. In the introductory paragraphs, a short perspective is provided on the current importance of plants in the discovery of cancer therapeutic agents, and the contributions of other groups working towards this objective are mentioned. For our own investigations, following their collection, tropical plants have been subjected to solvent extraction and biological evaluation for their antitumor potential. Several examples of purified plant lead bioactive compounds were obtained and characterized, and found to exhibit diverse structures, including those of the alkaloid, cardiac glycoside, coumarin, cucurbitacin, cyclobenzofuran (rocaglate), flavonoid, lignan, and terpenoid types. In order to maximize the efficiency of work on drug discovery from tropical plant species, strategies to optimize various research components have been developed, including those for the plant collections and taxonomic identification, in accordance with the requirements of contemporary international treaties and with a focus on species conservation. A major component of this aspect of the work is the development of collaborative research agreements with representatives of the source countries of tropical rainforest plants. The phytochemical aspects have included the preparation of plant extracts for initial screening and the selection of promising extracts for activity-guided fractionation. In an attempt to facilitate this process, a TOCSY-based NMR procedure has been applied for the determination of bioactive rocaglate derivatives in samples of Aglaia species (Meliaceae) collected for the project. Preliminary in vitro and in vivo mechanistic studies carried out by the authors are described for two tropical plant-derived bioactive lead compounds, corchorusoside C and (+)-betulin, including work conducted with a zebrafish (Danio rerio) model. In the concluding remarks, a number of lessons are summarized that our group has learned as a result of working on anticancer drug discovery using tropical plants, which we hope will be of interest to future workers.


Assuntos
Antineoplásicos , Descoberta de Drogas , Fitoterapia , Extratos Vegetais , Floresta Úmida , Animais , Antineoplásicos/farmacologia , Extratos Vegetais/química , Plantas/química , Peixe-Zebra , Clima Tropical , Sudeste Asiático , Modelos Animais
7.
Nature ; 618(7964): 316-321, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225981

RESUMO

In the United Nations Decade on Ecosystem Restoration1, large knowledge gaps persist on how to increase biodiversity and ecosystem functioning in cash crop-dominated tropical landscapes2. Here, we present findings from a large-scale, 5-year ecosystem restoration experiment in an oil palm landscape enriched with 52 tree islands, encompassing assessments of ten indicators of biodiversity and 19 indicators of ecosystem functioning. Overall, indicators of biodiversity and ecosystem functioning, as well as multidiversity and ecosystem multifunctionality, were higher in tree islands compared to conventionally managed oil palm. Larger tree islands led to larger gains in multidiversity through changes in vegetation structure. Furthermore, tree enrichment did not decrease landscape-scale oil palm yield. Our results demonstrate that enriching oil palm-dominated landscapes with tree islands is a promising ecological restoration strategy, yet should not replace the protection of remaining forests.


Assuntos
Biodiversidade , Produtos Agrícolas , Recuperação e Remediação Ambiental , Óleo de Palmeira , Árvores , Florestas , Óleo de Palmeira/provisão & distribuição , Árvores/fisiologia , Agricultura/métodos , Nações Unidas , Clima Tropical , Produtos Agrícolas/provisão & distribuição , Recuperação e Remediação Ambiental/métodos
8.
J Anim Ecol ; 92(2): 466-476, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36479696

RESUMO

Bottom-up effects from host plants and top-down effects from predators on herbivore abundance and distribution vary with physical environment, plant chemistry, predator and herbivore trait and diversity. Tri-trophic interactions in tropical ecosystems may follow different patterns from temperate ecosystems due to differences in above abiotic and biotic conditions. We sampled leaf-chewing larvae of Lepidoptera (caterpillars) from a dominant host tree species in a seasonal rainforest in Southwest China. We reared out parasitoids and grouped herbivores based on their diet preferences, feeding habits and defence mechanisms. We compared caterpillar abundance with leaf numbers ('bottom-up' effects) and parasitoid abundance ('top-down' effects) between different seasons and herbivore traits. We found bottom-up effects were stronger than top-down effects. Both bottom-up and top-down effects were stronger in the dry season than in the wet season, which were driven by polyphagous rare species and host plant phenology. Contrary to our predictions, herbivore traits did not influence differences in the bottom-up or top-down effects except for stronger top-down effects for shelter-builders. Our study shows season is the main predictor of the bottom-up and top-down effects in the tropics and highlights the complexity of these interactions.


Assuntos
Herbivoria , Lepidópteros , Plantas , Animais , Ecossistema , Lepidópteros/parasitologia , Plantas/parasitologia , Floresta Úmida , Estações do Ano , Clima Tropical , China
9.
Trop Anim Health Prod ; 54(5): 308, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36114327

RESUMO

Relatively, little is known about the corpus luteum (CL) function in early pregnancy after the successful treatment of luteal phase deficiency in repeat-breeder dairy cows when exposed to extreme environments under tropical climate. To investigate the influence of increased tissues of corpora lutea (CLs) by inducing secondary CL based on progesterone (P4) concentration and fertility in repeat-breeder dairy cows undergoing the fixed-time artificial insemination (FTAI) protocol, 32 cows were treated with gonadotropin releasing hormone (GnRH) on day 5 post-induction (experiment 1). In experiment 2, 213 cows were bred using the short-term FTAI protocol. On day 5 post-FTAI, cows were divided into two groups: treatment with (GnRH5-treated group) or without (GnRH5-untreated group) GnRH. The temperature-humidity index ranged from 77.3 to 82.8. Cows bearing two CLs had greater P4 concentrations than cows bearing only one CL on their ovaries (P < 0.05). Pregnancy rates were greater in GnRH5-treated group than the GnRH5-untreated group (P < 0.01). Moreover, repeat-breeder cows bearing two CLs had a greater likelihood of pregnancy (odds ratio = 20.86) than cows bearing only one CL on their ovaries (P < 0.01). Under heat stress condition, the results highlighted that increasing luteal tissues by creating secondary CL leads to enhanced peripheral P4 concentrations and improved pregnancy outcomes in repeat-breeder dairy cows.


Assuntos
Progesterona , Clima Tropical , Animais , Bovinos , Corpo Lúteo , Feminino , Fertilidade , Hormônio Liberador de Gonadotropina/farmacologia , Resposta ao Choque Térmico , Gravidez , Progesterona/farmacologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-35742508

RESUMO

(1) Solar ultraviolet radiation (UVR) poses a major risk factor for developing skin cancer after years of chronic exposure. The irradiation is strongly dependent upon the activity or occupation carried out, but also on the climate conditions at the workplace. Knowledge of both has been tested within the occupational group of road construction workers in Colombia and Germany. (2) The GENESIS-UV measurement system has been used at both locations for consistency. A number of workers in both countries wore an electronic data logging dosimeter for several months to deliver detailed information on UVR exposure. (3) It was found that in a tropical climate, UVR exposure remains constant throughout the year, while in a temperate climate seasonal effects are visible, superimposed by behavioural aspects e.g., in springtime. The daily distribution of the radiation shows a distinct dip, especially in the Colombian data. Derived data show the high fraction of working days exceeding a threshold set by the skin type. (4) Road construction work involves high UVR exposure. In both countries, preventive measures are required to reduce the personal exposure to a minimum. Exceedance of the minimal erythema dose (MED) suggests a possible enhancing effect, especially in fair skinned people. Intercomparison of UVR exposure at workplaces is possible between countries and climate zones, emphasizing efforts for global action against skin cancer.


Assuntos
Indústria da Construção , Exposição Ocupacional , Neoplasias Cutâneas , Colômbia , Alemanha , Humanos , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Clima Tropical , Raios Ultravioleta/efeitos adversos
11.
Theriogenology ; 189: 127-136, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35753226

RESUMO

Environmental heat stress in sub-tropical climates negatively impacts boar semen production and its quality. The present study aimed to examine the heat stress alleviating effects of dietary linseed oil on semen quality and antioxidant status of boar, in the summer and winter seasons in sub-tropical climate. Six Hampshire crossbreed boars were fed with 90 mL linseed oil (treatment) whereas six boars of the same breed were fed 90 mL vegetable oil (control) for sixteen weeks during both season. Sperm quality was assessed for motility, viability, abnormality, acrosomal integrity, and Hypo-osmotic swelling test (HOST). Sperm velocity attributes were assessed by computer-assisted semen analysis (CASA). Antioxidants (glutathione peroxidase; GPx, catalase; CAT, total antioxidant capacity; TAC and nitric oxide; NO) and lipid peroxidation (malondialdehyde; MDA) were measured in seminal plasma and serum. Gas chromatography-mass spectrometry (GC-MS) was used for the estimation of fatty acid composition of seminal plasma and spermatozoa. Feeding linseed oil to the boars significantly (p < 0.05) improved sperm quality at the fresh stage and after 72 h of liquid storage in both season. There was a significant (p < 0.01) effect of treatment and season on semen quality parameters. Significant boar (p < 0.05) effect was recorded on reaction time, semen volume, sperm abnormality, acrosomal integrity and HOST reactive sperm. There was a significant (p < 0.01) effect of treatment and season on the velocity attributes viz. VAP, VSL, VCL, ALH, BCF and STR%. Linseed oil supplementation significantly (p < 0.01) enhanced antioxidant and lowered MDA levels in serum as well as seminal plasma. The concentration of alpha-linolenic (ALA), arachidonic and docosahexaenoic (DHA) fatty acids were significantly (p < 0.01) increased in seminal plasma and sperm after linseed oil supplementation. In conclusion, linseed oil supplementation to boar during high THI months improved the semen quality parameters viz. semen volume, sperm concentration, and progressive motile sperm, along with enhanced antioxidant capacity.


Assuntos
Antioxidantes , Análise do Sêmen , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Dieta/veterinária , Ácidos Graxos/farmacologia , Umidade , Óleo de Semente do Linho/farmacologia , Masculino , Melhoramento Vegetal , Sêmen/química , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Suínos , Temperatura , Clima Tropical
12.
Sci Rep ; 12(1): 10684, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739146

RESUMO

In order to expand the output of solar power systems for efficient integration into the national grid, solar energy resource assessment at site is required. A major impediment however, is the widespread scarcity of radiometric measurements, which can be augmented by satellite observation. This paper assessed the suitability of satellite-based solar radiation resource retrieved from the NASA-POWER archives at [Formula: see text] spatial resolution over Ghana-West Africa, to develop a long-term source reference. The assessment is based on the criteria of comparison with estimations from sunshine duration measurement for 22 synoptic stations. Overall, the satellite-based data compared well with ground-based estimations by r = 0.6-0.94 ± 0.1. Spatiotemporally, the agreement is strongest over the northern half Savannah-type climate during March-May, and weakest over the southern half Forest-type climate during June-August. The assessment provides empirical framework to support solar energy utilization in the sub-region.


Assuntos
Energia Solar , Florestas , Gana , Clima Tropical , Estados Unidos , United States National Aeronautics and Space Administration
13.
J Therm Biol ; 104: 103199, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35180975

RESUMO

West Indian drywood termites (Cryptotermes brevis, Blattodea: Kalotermitidae) are an important invasive termite in many countries including Australia where they are spreading across two eastern states. Fumigation is often used to eliminate infestations, but it is costly, has negative environmental effects and does not prevent reinfestation. Heat treatment has been suggested as an alternative. Many insect pest mitigation strategies recommend 30 min exposure at 56 °C, but this may be difficult to achieve in structural applications. The potential for heating at lower temperatures was explored to determine the effect on termite survival and gut fauna. Exposure to 40 °C up to an hour did not kill the termites; however, 1-h exposure at 45 °C was lethal. Exposure for little as 3 min at 50 °C or 2 min at 55 °C was lethal. Protozoa levels were lower in termites that survived shorter exposures, but there appeared to be some recovery over time. The results suggest that short term exposures to 50 or 55 °C could be used to eliminate infestations, creating an opportunity for localized spot heating as a mitigation measure.


Assuntos
Baratas/fisiologia , Isópteros/fisiologia , Termotolerância , Árvores , Animais , Austrália , Espécies Introduzidas , Temperatura , Clima Tropical
14.
Sci Rep ; 12(1): 2826, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35181709

RESUMO

Dry dipterocarp forests are among the most common habitat types in Thailand. Russulaceae are known as common ectomycorrhizal symbionts of Dipterocarpaceae trees in this type of habitat. The present study aims to identify collections of Russula subsection Amoeninae Buyck from dry dipterocarp forests in Thailand. A multi-locus phylogenetic analysis placed Thai Amoeninae collections in two novel lineages, and they are described here as R. bellissima sp. nov. and R. luteonana sp. nov. The closest identified relatives of both species were sequestrate species suggesting that they may belong to drought-adapted lineages. An analysis of publicly available ITS sequences in R. subsect. Amoeninae did not confirm evidence of any of the new species occurring in other Asian regions, indicating that dry dipterocarp forests might harbor a novel community of ectomycorrhizal fungi. Macromorphological characters are variable and are not totally reliable for distinguishing the new species from other previously described Asian Amoeninae species. Both new species are defined by a combination of differentiated micromorphological characteristics in spore ornamentation, hymenial cystidia and hyphal terminations in the pileipellis. The new Amoeninae species may correspond to some Russula species collected for consumption in Thailand, and the detailed description of the new species can be used for better identification of edible species and food safety in the region.


Assuntos
Basidiomycota/genética , DNA Fúngico/isolamento & purificação , Dipterocarpaceae/genética , Filogenia , Basidiomycota/classificação , DNA Fúngico/genética , Dipterocarpaceae/classificação , Ecossistema , Florestas , Micorrizas/classificação , Micorrizas/genética , Tailândia , Clima Tropical
15.
Nat Plants ; 8(2): 104-109, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35115726

RESUMO

The latitudinal biodiversity gradient, with tropical regions acting as 'evolutionary cradles', is a cornerstone of current biogeographical and ecological theory1. In the modern world floral biodiversity and biomass are overwhelmingly concentrated in the tropics, and it is often assumed that the tropics were evolutionary cradles throughout land plant evolutionary history. For example, the origination and diversification of angiosperms is believed to have taken place in the Cretaceous tropics2 and modern gymnosperms in the Permian tropics3. Here, we show that during the first major diversification of land plants, in the Late Silurian-Early Devonian, land plant biodiversity was much lower at the equator compared to medium-high southern latitudes. Throughout this crucial interval of plant evolution, tropical vegetation remained depauperate and of very low taxonomic biodiversity, although with similar morphological disparity to the more diverse higher latitude floras. Possible explanations for this low tropical floral biodiversity include palaeocontinental configuration or adverse palaeotropical environmental conditions. We discount the possibility that it was simply a fortuitous feature of the biogeographical spread of the earliest vascular land plants.


Assuntos
Magnoliopsida , Clima Tropical , Biodiversidade , Evolução Biológica , Cycadopsida , Filogenia
16.
Curr Opin Insect Sci ; 50: 100878, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35093582

RESUMO

Global pest invasions have significantly increased in recent years. These invasions together with climate warming directly impact agriculture. Tropical climates feature extreme weather events, including high temperatures and seasonal droughts. Thus, successful invasive pests in tropics have to adapt to these extreme climate features. The intrinsic factors relevant to tropical invasion of insects have been explored in many studies, but the knowledge is rather dispersed in contemporary literature. Here, we reviewed the potential biophysical characters of successful invasive pests' adaption to tropical environments including [1] inherent high basal stress tolerance and advanced life-history performances [2], phenotypic plasticity [3], rapid evolution to environmental stress, polyphagy, diverse reproductive strategies and high fecundity. We summarised how these traits and their interactive effects enhance pest invasions in the tropics. Comprehensive understanding of how these characters facilitate invasion improves models for predicting ecological consequences of climate change on invasive pest species for improved pest management.


Assuntos
Mudança Climática , Plásticos , Animais , Insetos , Espécies Introduzidas , Clima Tropical
17.
Glob Chang Biol ; 28(4): 1583-1595, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34854168

RESUMO

Our limited understanding of the impacts of drought on tropical forests significantly impedes our ability in accurately predicting the impacts of climate change on this biome. Here, we investigated the impact of drought on the dynamics of forest canopies with different heights using time-series records of remotely sensed Ku-band vegetation optical depth (Ku-VOD), a proxy of top-canopy foliar mass and water content, and separated the signal of Ku-VOD changes into drought-induced reductions and subsequent non-drought gains. Both drought-induced reductions and non-drought increases in Ku-VOD varied significantly with canopy height. Taller tropical forests experienced greater relative Ku-VOD reductions during drought and larger non-drought increases than shorter forests, but the net effect of drought was more negative in the taller forests. Meta-analysis of in situ hydraulic traits supports the hypothesis that taller tropical forests are more vulnerable to drought stress due to smaller xylem-transport safety margins. Additionally, Ku-VOD of taller forests showed larger reductions due to increased atmospheric dryness, as assessed by vapor pressure deficit, and showed larger gains in response to enhanced water supply than shorter forests. Including the height-dependent variation of hydraulic transport in ecosystem models will improve the simulated response of tropical forests to drought.


Assuntos
Secas , Ecossistema , Mudança Climática , Florestas , Árvores , Clima Tropical
18.
J Plant Physiol ; 268: 153559, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34839100

RESUMO

Canavalia rosea (Sw.) DC is a perennial twining herb distributed in the semi-arid and saline-alkali areas of coastal regions and has evolved halotolerance. In this study, we present the first comprehensive survey of the metallothionein (MT) gene family in C. rosea. MT proteins belong to a family of low-molecular-weight polypeptides with a high content of cysteine residues, which have an affinity to bind with heavy metal ions. MTs also play important roles in stress responses as reactive oxygen species (ROS) scavengers. A total of six CrMTs were identified in the C. rosea genome and classified into four subgroups by phylogenetic analysis. An analysis of the cis-acting elements revealed that a series of hormone-, stress-, and development-related cis-acting elements were present in the promoter regions of CrMTs. The expression of CrMTs also showed habitat- and environmental stress-regulated patterns in C. rosea. CrMT overexpression in yeast enhanced tolerance to heavy metals and ROS, as well as high osmotic and alkalinity stress, which is consistent with their predicted roles as metal-chelating proteins and ROS scavengers. Our results indicate that the CrMT genes might contribute to the detoxification of plants to metals and provide marked tolerance against abiotic stress. The expression patterns of CrMTs in C. rosea also indicate that CrMTs play important roles in this species' response to extreme environments on tropical islands and reefs, probably by improving the thermotolerance of C. rosea plants.


Assuntos
Canavalia , Metalotioneína , Metais Pesados , Adaptação Fisiológica , Canavalia/efeitos dos fármacos , Canavalia/genética , Recifes de Corais , Genes de Plantas , Metalotioneína/genética , Metais Pesados/toxicidade , Família Multigênica , Filogenia , Espécies Reativas de Oxigênio , Clima Tropical
19.
Cienc. tecnol. salud ; 9(2): 150-165, 2022. il 27 c
Artigo em Espanhol | LILACS, DIGIUSAC, LIGCSA | ID: biblio-1415622

RESUMO

El objetivo de esta investigación consistió en explorar el comportamiento histórico de la temperatura, precipitación y la radiación saliente de onda larga (OLR) para Guatemala, durante el período de sequía de medio verano (canícula). El procedimiento metodológico partió del uso de la base de datos de 38 estaciones meteorológicas del Instituto Nacional de Sismología, Vulcanología, Meteorología e Hidrología, de Guatemala (Insivumeh), del periodo de 1971-2019. Se realizaron promedios para cada región del país; Norte, Caribe, Franja Trasversal, Pacífico, Boca Costa, Oriente y Altiplano. Mediante series de tiempo con resolución temporal diaria, se evaluaron señales de cambio y se hicieron gráficas de OLR con la base de datos del Centro Nacional de Predicción Ambiental (NCEP, por sus siglas en inglés) de 2.5° x 2.5° de resolución. Los resultados muestran que la temperatura ha aumentado en dicho periodo, encontrando que en algunas regiones climáticas el aumento ha sido de 1 ºC y en otras de 2 ºC. Asimismo, se encontró que los días sin lluvia tienen una tendencia hacia el aumento, al igual que la radiación saliente de onda larga. La canícula, es un fenómeno meteorológico que está siendo afectado por el cambio climático, y en la medida que se siga experimentando un calentamiento diferencial entre los océanos Pacífico y Atlántico, influirá en el cambio de clima para Guatemala. En conclusión, durante la canícula se manifestaron señales de tendencia hacia el aumento de la temperatura, aumento de días sin lluvia y aumento de OLR.


The objective of this research was to explore the historical behavior of temperature, precipitation and outgoing longwave radiation (OLR) for Guatemala, during the midsummer drought period (canícula). The methodological procedure was based on the use of the database of 38 stations of the National Institute of Seismology, Volcanology, Meteorology and Hydrology, of Guatemala (Insivumeh), from the period 1971-2019. Averages were made for each region of the country; North, Caribbean, Transversal Strip, Pacific, Boca Costa, East and Altiplano. Using time series with daily temporal resolution, signals of change were evaluated and OLR plots were made using the National Center for Environmental Prediction (NCEP) database at 2.5° x 2.5° resolution. The results show that the temperature has reached in this period, finding that in some climatic regions the increase has been 1 ºC and in others 2 ºC. Likewise, it was found that the days without rain have a tendency to increase, as well as the outstanding longwave radiation. The heat wave is a meteorological phenomenon that is being affected by climate change, and to the extent that differential heating between the Pacific and Atlantic oceans continues to be experienced, it will influence the climate change for Guatemala. In conclusion, during the heat wave there are signs of a trend towards an increase in temperature, an increase in days without rain and an increase in OLR,


Assuntos
Chuva , Climatografia , Pluviometria , Secas/estatística & dados numéricos , Estações do Ano , Clima Tropical , Zonas Climáticas , Estações Meteorológicas , Aquecimento Global/estatística & dados numéricos , Guatemala
20.
Rev. bras. parasitol. vet ; 31(3): e007522, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1394891

RESUMO

Abstract Birds of prey harbor a wide spectrum of various parasites, mostly with a heteroxenous life cycle. However, most reports on their parasites come from Europe. Although the Harris's hawk (Parabuteo unicinctus) is a widespread species in America, parasitological surveys on this hawk are mostly focused on coprological findings and ectoparasites, with poor attention paid to helminths. The aim of this study was to gather new and additional data on host-parasite associations for the Harris's hawk. Twenty-nine birds from central and southern Chile were necropsied. Further, nine birds from a rehabilitation center and 22 museum specimens were inspected for ectoparasites. Sixty-eight percent of birds hosted at least one parasite species. Four lice species, one mite species and eight helminth species (five nematodes, two platyhelminthes and one acanthocephalan) were recorded. Parasitic lice Colpocephalum nanum and Nosopon chanabense, and a nematode Cyathostoma (Hovorkonema) americana were recorded for the first time in raptors from the Neotropics. A feather mite, Pseudalloptinus sp., nematodes, Physaloptera alata and Microtetrameres sp., and a trematode Neodiplostomim travassosi, were recorded for the first time in Chile. The presence of diverse heteroxenous helminths reported here in the Harris's hawk could be explained by the generalist diet of this raptor.


Resumo As aves de rapina representam uma fonte importante de parasitas heteroxenos. Porém, a maioria dos relatos são da Europa. O gavião-asa-de-telha (Parabuteo unicinctus) é uma espécie amplamente distribuída no continente Americano, porém estudos parasitológicos nessas aves têm documentado achados coprológicos e ectoparasitas, com poucos relatos sobre endoparasitas como helmintos. Por essa razão, o objetivo deste estudo foi descrever novas associações parasita-hospedeiro para o gavião-asa-de-telha e rapinantes neotropicais. Vinte nove aves provenientes do centro e sul do Chile foram submetidas à necropsia. Por outro lado, nove aves de um centro de reabilitação e 22 espécimes de museu foram inspecionados em busca de ectoparasitas. Do total de aves, 68,3% foram identificadas como portadoras de pelo menos uma espécie de parasita. Quatro espécies de piolhos, um ácaro e oito helmintos (cinco nematoides, dois platelmintos e um acantocéfalo) foram registrados. Os piolhos Colpocephalum nanum, Nosopon chanabense e o nematóide Cyathostoma (Hovorkonema) americana são reportados pela primeira vez em rapinantes neotropicais. Colpocephalum nanum, N. chanabense, Pseudalloptinus sp., Physaloptera alata, Microtetrameres sp., C. (H.) americana e Neodiplostomim travassosi, são reportados pela primeira vez no Chile. A diversidade de helmintos heteróxenos, identificados neste trabalho, poderia ser explicada devido à dieta geralista do gavião-asa-de-telha.


Assuntos
Animais , Masculino , Feminino , Falcões/parasitologia , Helmintos/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Ftirápteros/fisiologia , Ácaros/fisiologia , Platelmintos/isolamento & purificação , Autopsia/veterinária , Clima Tropical , Bico/parasitologia , Doenças das Aves/epidemiologia , Chile/epidemiologia , Prevalência , Ectoparasitoses/veterinária , Ectoparasitoses/epidemiologia , Distribuição por Idade e Sexo , Acantocéfalos/isolamento & purificação , Plumas/parasitologia , Helmintíase Animal/epidemiologia , Nematoides/isolamento & purificação
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