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Biologia
Journal Prestige (SJR): 0.299  Citation Impact (citeScore): 1 Number of Followers: 1  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1336-9563 - ISSN (Online) 0006-3088 Published by Springer-Verlag  [2468 journals]
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- Comparative stereo scanning studies on sense organs of some terrestrial
spiders at Assiut, Egypt-
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Abstract: Abstract Sensory organs reflect the effects of stimuli and reveal the biological events in their outside and inside environments. The behaviour of spiders is controlled by the central nervous system like in other animals. Spiders contain several types of sensory organs that help them recognize their surroundings. These sensory organs may have mechanoreceptor or chemoreceptor functions. All parts of the spider’s body contain different hairs, sensillae, setae and spines. The function of sensory structures is affected by their site in the spider’s body. This study aimed at describing different types, distribution and functions of sensory organs of five ground spiders inhabiting Assiut Governorate, Egypt. Fifty samples of spider specimens were collected by hand picking and pitfall traps during years 2016 and 2017 from different habitats. The specimens were examined under a binocular stereomicroscope and scanning electron microscope. The study revealed the presence of sensory organs on different body parts of the studied spiders, including sensilla trichodea, sensilla placodea, sensilla basiconica, sensilla styloconica, setae, trichobothria and slit sense organs (Lyriform organs). A significant difference in the position and type of sensory organs was detected between males and females of different spider species.
PubDate: 2024-08-06
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- Klebsiella pneumoniae clinical isolates: extended spectrum β-lactamase
production, biofilm formation, and virulence factors-
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Abstract: Abstract Klebsiella pneumoniae, a Gram-negative bacterium that has emerged as a significant global threat, has been implicated in nosocomial infections. The objectives of this investigation encompassed: i) assessment of extended spectrum ß-lactamase (ESBL) synthesis and other forms of antibiotic resistance, ii) characterization of biofilm formation, adhesin (fimH), and capsule (uge) virulence genes, and iii) exploration of the existence of Class-1 integron (intI1) within the isolates. A total of 120 K. pneumoniae were obtained from clinical specimens and identified with automatic Vitek®2 compact systems. The rates of resistance to various antibiotics were as follows: levofloxacin 89.1%, amoxicillin-clavulanic acid 69.1%, ceftazidime 60%, fosfomycin 59.1%, aztreonam 57.5%, nalidixic acid 56.6%, piperacillin-tazobactam 54.1%, tobramycin 44.1%, chloramphenicol 40%, gentamycin and meropenem 39.1%, imipenem 35.8%. Combined disc testing identified 28 isolates (23.3%) as ESBL-producing K. pneumoniae. The frequency of genes encoding ESBLs is reported as follows: blaTEM 10 (8.3%), blaSHV 42 (35%), and blaCTX-M-I 23 (19.1%). The virulence genes encountered in isolates were adhesin and capsule, 22.5% fimH and 21.6% uge, respectively. The intI1 gene was detected in 70 (58.3%) isolates. Biofilm analysis revealed that 58 isolates (48.3%) were biofilm producers. This study is important for preventing K. pneumoniae infection as it reveals the relationship between antibiotic resistance of isolates, virulence factors, and biofilm formation.
PubDate: 2024-08-06
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- A checklist of chaetognaths along the eastern Arabian sea
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Abstract: Abstract Chaetognatha, the second-most abundant zooplankton in the marine ecosystem, is a connecting link between copepods and organisms of the higher trophic level. The present checklist provides detailed information on the morphology and distribution of chaetognaths in the eastern Arabian Sea (northeastern Arabian Sea, southeastern Arabian Sea, and Laccadive Sea). It includes five families under two orders with 34 species belonging to 15 genera and recorded from both shelf, oceanic and deep sea waters of the eastern Arabian Sea, creating a first line data on chaetognaths of the Arabian Sea.
PubDate: 2024-08-02
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- Harmfulness and biological characters of a leaf beetle Gastrolina depressa
(Coleoptera: Chrysomelidae) to its host plant Pterocarya stenoptera
(Fagales: Juglandaceae)-
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Abstract: Abstract Gastrolina depressa (Coleoptera: Chrysomelidae) has been found to damage many walnut plants in China. It prefers to feed on the annual leaves of an important economic plant, Pterocarya stenoptera (Fagales: Juglandaceae), and causes extensive cosmetic destruction, even plant death. Nevertheless, its biological characteristics are mostly unknown. In this study, we investigate the harmful and biological characteristics of G. depressa with different developmental stages. The results showed that G. depressa had four developmental stages: egg, larva (1st -3rd instar), pupa, and adult, the life history lasted nine days, with obvious overlapping generations. The food intake of the larvae increased with the increase of the instar, and the maximum food intake of the 3rd instar larvae was 448.19 mm2. The abdomen of the females was enlarged before oviposition, and the average number of eggs laid was 47.63 ± 13.53. Bioassay showed that there was no difference in the search time for the young (2.03, 1.25, 1.15, and 0.91 min) and old leaves (1.68, 1.15, 0.90, and 1.93 min) of P. stenoptera between 1st -3rd instar larvae and adults; the feeding preference of 1st -3rd instar larvae and adults for young leaves was higher than that to old leaves (23.33%, 26.67%, 33.33%, and 21.67%, respectively). The successful selection rates of 1st -3rd instar larvae and adults to young leaves (81.67%, 80%, 85.00%, and 70.00%, respectively) was higher than to old leaves (8.35%, 11.67%, 3.34%, and 11.67%, respectively).
PubDate: 2024-08-02
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- Searching for mates may shape parental investment and immune response
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Abstract: Abstract A wide variety of strategies have emerged in different animal species for attracting mates. These strategies, such as chemical signals and calling songs, fuel competition for mates and can lead to the evolution of distinct courtship behaviours within a species. These behaviours often involve males and females taking on different roles in attracting mates. For example, limitations in signal production or perception can make one of the sexes sedentary. Regarding Poecilimon bushcrickets specifically, in 2012 McCartney et al. proposed a theory to explain sex role differentiation within the mate-searching system in certain species. According to this model, sex roles in mate-searching systems propose that in species where females search for males, females should receive a larger spermatophore gift. This study tests this theory for two Poecilimon species with differing strategies in terms of females’ response to male calling songs regarding spermatophore investment (P. sureyanus-female searching and P. inflatus-male searching). Given that reproductive effort and physiological activities are both costly for the organism, there is a trade-off due to limited energy resources. To investigate the specific trade-off in allocating resources between reproductive functions and immune defence in these species, the presents study compared two immune parameters (phenoloxidase and lytic activities). In nature, immune activities are much more plastic than the differentiation of reproductive traits between the sexes. The results showed that spermatophore investment may critically depend on differences in mate-searching strategies, particularly in terms of females’ response to male calling songs within the species. The findings also indicated that there may be trade-offs between the costs related to reproduction and the immune system.
PubDate: 2024-08-02
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- Evaluation of the antiproliferative and oxidative effects of HEMA based
polymeric cryogels including N-vinyl formamide on the model eukaryotic
yeast Saccharomyces cerevisiae-
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Abstract: Here, the effects of previously characterized poly(HEMA-N-vinyl formamide) (PHEMA-NVF) cryogels on viability, surface morphology, total antioxidant-oxidant status, antioxidant enzyme activities, and biochemical makeup of Saccharomyces cerevisiae were investigated for the first time. The cells' viability from the PHEMA-NVF cryogels exhibited a significant drop of 23.96 ± 1.44% compared to the plain PHEMA cryogel, which served as the control group without NVF. Additionally, this cryogel caused blebbing and holes on the cell surface. Despite the gradual increase in TOS levels with increasing NVF amounts, only the cryogel containing 3.12 mmol NVF showed a statistically significant difference from the control. The gradual increases in TAS levels in response to cellular stress were recorded depending on the increase in NVF amounts up to 3.12 mmol. While the enzymatic antioxidant system was generally induced in cells released from the cryogel prepared with relatively low levels of NVF, these activities dramatically decreased at higher amounts of the comonomer. Finally, FTIR analysis revealed that the highest concentration of NVF caused protein degradation and increased the relative concentration of lipid and polysaccharide molecules. Therefore, we can suggest that this comonomer induces oxidative stress, which the cell cannot tolerate beyond a certain threshold. Graphical
PubDate: 2024-08-02
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- Effects of different feeding methods and hosts on the fecundity and
blood-feeding behavior of Aedes aegypti and Aedes albopictus (Diptera:
Culicidae)-
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Abstract: Abstract Aedes aegypti and Aedes albopictus are predominantly daytime-feeding mosquito species that breed in urban settlements and transmit viral and nematode diseases. Females can feed on a broad range of vertebrate hosts for oogenesis. Research on host-feeding behavior and patterns is important to better understand the transmission cycles of most mosquito-borne diseases and to develop better protection measures. This study investigated the host feeding patterns of Ae. aegypti and Ae. albopictus through both artificial blood feeding and natural feeding techniques and assessed the effect of these methods on mosquito fecundity. Laboratory colonies of both mosquitoes fed on blood from five different hosts (bird, mouse, human, sheep and cow). The artificial blood feeding system consisted of a glass condenser with blood attached to a water bath with warm water circulation and insects fed through a stretched Parafilm membrane over the bottom of the condenser. Natural feeding experiments were performed with paper cups that contained the mosquitoes and were placed over the host’s skin for one hour. In the natural feeding method, Ae. aegypti females mostly fed on humans, while in the artificial blood feeding method, they fed on birds. Both human and bird blood sources yielded the highest number of eggs, larvae and pupae for Ae. aegypti. Aedes albopictus preferred humans in the natural feeding method and mice in the artificial blood feeding method. Similarly, egg, larvae and pupae productivity from humans and mice were also high for Ae. albopictus. Both species preferred the artificial feeding method. Our findings show that different blood meal sources and methods affect mosquito fecundity. Such laboratory studies on mosquito feeding patterns can reveal the feeding preference of important vectors and provide vital information for understanding vector and host interactions.
PubDate: 2024-08-01
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- Antimicrobial peptides: a novel and natural approach as antibiofouling
mediator-
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Abstract: Abstract Antimicrobial peptides (AMPs) are natural ribosomal synthesized small peptides and are crucial effectors in all living organisms. AMPs are diverse polypeptides with varying amino acid composition and structure that often exhibit broad-spectrum and fast-acting antibacterial properties. As a result, AMPs offer a great deal of promise for restorative application in medicine, agriculture, and the environment. The maritime, industrial, and healthcare sectors all suffer major losses as a result of biofouling. This article will review antimicrobial peptides (AMPs), their structure and major class of AMPs that are reported as anti-biofouling agents, evolutionary concept of AMP, mechanism of action of AMPs against biofilm formation, intracellular active AMPs, synthetic AMPs, promising AMP modifications reported and AMP databases to understand AMPs specificity and activity for rational designing. Therefore, this review will provide a comprehensive assessment of AMPs numerous functions as well as to detect their therapeutic potential and avoid industry losses incurred by biofilms.
PubDate: 2024-08-01
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- First insights into the complete mitochondrial genome of a deep-sea eel
Congriscus megastoma (Anguilliformes, Congroidei, Congridae):
characterization and phylogenetic inference-
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Abstract: Abstract The complete mitochondrial DNA sequence of a deep-sea eel Congriscus megastoma (Anguilliformes: Congridae) was determined by high throughput sequencing technology. As the first mitogenome of the genus Congriscus up to now, its entire mtDNA sequence was 17,616 bp in length, including 37 mitochondrial genes (13 protein-coding genes, 2 rRNA genes, 22 tRNA genes) and 2 control regions, which was inconsistent with that of the typical vertebrate mitogenomes. In addition, the genes of C. megastoma exhibited an obvious rearrangement. ND6 and tRNA-Glu were transferred between tRNA-Thr and tRNA-Pro, as well as a doubled control region appeared. The tandem duplication-random loss (TDRL) model was an ideal explanation for this irregular gene reorganization phenomenon. The Bayesian phylogenetic tree showed that Congridae species were divided into four clades, suggesting their non-monophyletic origin. Congriscus had the closest relationships with Thalassenchelys and Coloconger. Species with gene rearrangement separately clustered as one clade. The results provided a basis for future studies of mitochondrial DNA structure and phylogeny of Anguilliformes.
PubDate: 2024-08-01
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- Biochemical analysis of defensive enzymes in the hemolymph of bivoltine
silkworm breeds of Bombyx mori (Lepidoptera: Bombycidae)-
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Abstract: Abstract To better cope with unfavorable climatic conditions and perform optimal physiological functions, the silkworm Bombyx mori secretes some of its defensive enzymes in the hemolymph. To understand the extent of enzyme secretion in the hemolymph, we studied the profiles of defense enzymes in different silkworm breeds. We collected and analyzed the hemolymph of 5th instar larvae of 21 different bivoltine silkworm breeds with different characteristics for protein content and activities of enzymes such as catalase, peroxidase, polyphenol oxidase, amylase, and protease. The results revealed significant differences between the breeds in terms of protein and defensive enzyme activities. The activity of catalase, peroxidase, polyphenol oxidase, amylase, and protease varied between silkworm breeds, with an average activity of 8.791 U mg−1, 0.203 U mg−1, 0.42 U mg−1, 0.264 mg ml−1 min−1 mg−1 and 0.193 µg ml−1 min−1, respectively. To understand the genetic relationship between the silkworm breeds in terms of the activity of defensive enzymes, we constructed a dendrogram using Euclidean distance. The 21 silkworm breeds were grouped into five different clusters with different enzyme activities, revealing sufficient diversity between the silkworm breeds that can be used for parental selection in silkworm breeding programs. This study is highly informative in enhancing knowledge on the role of defensive enzymes in the development of new silkworm breeds that can adapt to adverse environmental conditions.
PubDate: 2024-08-01
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- Keratin hydrolysates: a sustainable product in biotechnology sectors by
microbial conversion-
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Abstract: Abstract The increasing population and demand for food and feed have increased the urge to find protein sources from waste products. Due to poor management of waste valorization, it has become a pollutant to the environment. This waste can be converted into a valuable product by microbial degradation. Feather waste from poultry farms can be efficiently processed into hydrolysates, serving as an additive or in its crude form for animal feed and detergents. This approach not only reduces pollution but also boosts the economy of a country. Keratin is a hard fibrous protein, insoluble in water and organic solvents. They are accumulated in nature and are major components of feathers, nails, hairs, and wool. Microorganisms like bacteria, fungi, and actinomycetes can degrade keratin by producing the keratinase enzyme. Keratinases are thought to be promising biocatalysts for the production of animal nutrients, protein supplements, leather processing, fibre modification, detergent formulations, and pharmaceutical, cosmetic, and biomedical industries. An overview of keratin structure and composition, the mechanism of microbial hydrolysis of keratin, and their possible uses in biotechnological sectors are presented in this review.
PubDate: 2024-08-01
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- Biostimulatory effects of ascorbic acid in improving plant growth,
photosynthesis-related parameters and mitigating oxidative damage in
alfalfa (Medicago sativa L.) under salt stress condition-
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Abstract: Abstract Biostimulants such as ascorbic acid, known as vitamin C, have been reported to have numerous positive roles in plant tolerance to abiotic stresses. However, little is known about the biostimulant effects of ascorbic acid on alfalfa (Medicago sativa). Accordingly, a pot experiment was conducted to investigate the effects of 1 mM ascorbic acid, applied as foliar spray, on the salt tolerance of a Moroccan alfalfa population Demnate 201. One month-old M. sativa seedlings were exposed to 200 mM NaCl for four weeks with or without 1 mM of exogenous ascorbic acid treatment. The results showed that salinity stress significantly (p < 0.001) reduced plant biomass, disturbed photosynthesis-related parameters and induced oxidative stress. However, ascorbic acid foliar spray counteracted the observed negative effects of salinity. It significantly (p < 0.001) improved plant growth and photosynthetic parameters. Besides, stress indicators, including Na+ in shoot and root, hydrogen peroxide and electrolyte leakage, were significantly reduced by 42%, 29%, 12% and 34%, respectively, in treated and salt-stressed alfalfa plants. Interestingly, the decrease in oxidative stress markers was positively correlated to the ability of ascorbic acid to induce the accumulation of flavonoids and to increase the antioxidant activity of guaiacol peroxidase. Furthermore, compatible solutes, such as proline and soluble sugars, were found higher especially in salt-stressed alfalfa plants treated with 1 mM ascorbic acid. Our findings showed that ascorbic acid supply could be an eco-friendly and sustainable technique to mitigate the toxic effect of salt and could improve alfalfa forage production when grown in salt-affected soils.
PubDate: 2024-08-01
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- Sugar homeostasis in leaves during senescence and abiotic stress: role of
cell wall polysaccharides-
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Abstract: Abstract Historically leaf senescence, natural or stress-induced, was not taken seriously by plant physiologists. However, it is directly associated with plant productivity and nutrient economy. The complete execution of senescence and stress response is energy dependent. On the other hand, photosynthesis declines during the senescence process that limits supply of sugar to the leaf cells. Under sugar starvation environment, the cells search for alternative sources of sugar. Of course, the breakdown of cell deposits like starch, lipids and proteins provide the respiratory sugar at initial phase. However, these sources are likely to exhaust during the last phase of leaf senescence and the leaves experiencing stress. The possible role of cell wall polysaccharides in the maintenance of the sugar homeostasis during the late phase of leaf senescence and abiotic stresses is not much explored. The review will focus on the possible role of cell wall hydrolases that participate in the breakdown of cell wall polysaccharides and provide respiratory sugar, maintain cellular sugar homeostasis to execute and complete both senescence programme and stress response. The review will also emphasize on the loss of photosynthesis and, consequently loss of cellular sugar that possibly worked as the signal for induction and enhancement of the wall hydrolases to provide sugar to energy starved cells. Different groups of cell wall hydrolases such as exopolysaccharides, endopolysaccharides, and other hydrolases are involved in the coordinated loosing and the degradation of cell wall polysaccharides.
PubDate: 2024-08-01
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- Exploring small mammal diversity in Georgia (Sakartvelo) through DNA
barcoding-
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Abstract: Abstract Georgia is part of two biodiversity hotspots, the Caucasus and the Irano-Anatolian, both of which are characterized by high biological diversity and endemism rates. Eighty-one species of small mammals (Eulipotyphla, Chiroptera, Rodentia, and Leporidae) have been recorded in Georgia so far based on morphological identification. However, a comprehensive understanding of small mammal diversity requires integrative taxonomic approaches due to the cryptic nature and sympatric distribution of some taxa. Here, to develop a DNA barcode library, we re-evaluated the small mammal diversity of Georgia. Samples for DNA studies were collected during the last nine years throughout Georgia. The Cytochrome Oxidase Subunit I (COI) region of the mitochondrial genome was barcoded for collected samples, and a DNA barcode library was assembled. As a result, nearly 80% of the known species of Georgian small mammals were covered. Two species, Microtus rossiaemeridionalis (Ognev, 1924) and Myotis tschuliensis (Kuzyakin, 1935), were detected for the first time in Georgia. Furthermore, several problems were identified within the Chiroptera and Rodentia orders, requiring further studies.
PubDate: 2024-08-01
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- Production of fructo-oligosaccharide syrup through catalysis of Bacillus
amyloliquefaciens levanase and immobilized Ba-SacB on cell lysate-
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Abstract: Abstract Levan is a type of fructan with β-(2, 6) fructosyl linkage. In recent years, levan has been used in the medicinal, food and chemical industries for its excellent physicochemical properties of good thermal stability, low viscosity, pseudoplasticity, and non-swelling in water. The levansucrase is key enzyme responsible for biosynthesis of levan from substrate sucrose. In the present study cell lysate of Escherichia coli was used as support for convenient immobilization of Ba-SacB (i.e., Ba-SacB-Cell-Lysate) under the action of dopamine. Compared with the free Ba-SacB, the Ba-SacB-Cell-Lysate showed surprisingly enhanced pH stability in the pH range 6–9, and improved relative activities in the pH ranges 4–5 and 7–10. With the presence of 10% (v/v) butyl alcohol, 5mmol/L Fe3+, and after vortex for 90 min, the Ba-SacB-Cell-Lysate showed up to 14.32 times, 4.63 times, and 9.2 times higher relative activities than the free Ba-SacB. The Ba-SacB-Cell-Lysate kept nearly 81% of the residual activity after 9 cycles of reuse. The fructo-oligosaccharide syrup (FOS) was efficiently produced through the catalysis of levanase with the substrate of levan produced by Ba-SacB-Cell-Lysate, and the preparation conditions were optimized by Box-Behnken response surface methodology.
PubDate: 2024-08-01
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- In vitro lytic potential of Streptococcus bacteriophage against multidrug
resistant Streptococcus agalactiae-
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Abstract: Abstract Streptococcus agalactiae stands out as a significant bacterial pathogen, causing substantial economic losses in the aquaculture sector. Given the challenges posed by multidrug resistance, this study explores the potential of phage therapy as an alternative to antibiotics in biocontrol strategies. The focus is on evaluating the multidrug resistance profile of S. agalactiae isolated from a tilapia aquaculture farm, with particular attention to the strain KSA/01, which exhibits resistance to seven structurally different classes of antibiotics and a notable MAR index of around 0.6. In response to this challenge, the study successfully identifies and isolates the specific and lytic phage SAP-13 targeting the multidrug-resistant strain KSA/01. Transmission electron microscopy reveals that SAP-13 shares morphological characteristics with the Siphoviridae family. In a one-step growth curve, the phage demonstrates a substantial burst size of approximately 610 PFU/cell over a short burst period and the phage exhibited stability across various physicochemical parameters such as temperature, pH, and salinity. In vitro lytic ability of SAP-13 at different multiplicity of infection underscores its potential to effectively eliminate S. agalactiae, particularly at an MOI of 0.01. Consequently, these findings suggest that phage SAP-13 exhibits high infectivity against S. agalactiae, presenting a promising avenue for addressing multidrug-resistant strains in aquaculture.
PubDate: 2024-08-01
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- Hydrogen sulfide: a promising gasotransmitter for alleviating heavy metal
toxicity and promoting growth in plants-
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Abstract: Abstract Since the advent of industrialization, there has been a significant increase in the accumulation of heavy metals (HMs) in the soil, which further pose a major threat to plant growth and productivity. To address this issue and meet the global demand for food and energy, it is crucial to develop strategies that mitigate the toxicity induced by increased levels of HMs. One viable option is the supplementation of various phytohormones and gasotransmitters. Gasotransmitters are well-known for their ability to counteract a plethora of stresses in plants, with multifunctional hydrogen sulfide (H2S) being a promising candidate for reducing HM- induced oxidative stress. Furthermore, H2S has also been reported to regulate various physiological processes, such as seed germination, senescence and ageing in plants both under normal and stressed conditions. This review concurrently underscores the significance of H2S in plants subjected to HM stress. It also elucidates H2S’s role as both a standalone stress mitigator as well as a synergistic component when combined with other stress-alleviating agents, resulting in the mitigation of HM toxicity, enhanced plant growth, stabilization of physiological processes and the upregulation of antioxidative metabolic activities. Overall, this review accentuates the necessity for sustainable and eco-friendly approaches to manage HM stress and emphasizes the potential of H2S as a promising solution to alleviate HM-related damage to plants.
PubDate: 2024-08-01
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- Academic inbreeding reduces the scientific performance of ecologists
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Abstract: Abstract Academic inbreeding, defined as recruiting professionals from the same institution where they obtained their doctoral degrees, is characterized by low academic mobility. These inbred researchers can have lower scientific performance than the more mobile ones due to limited exposure to novel approaches and potential collaborations outside of their home institution. Despite the potential negative impact on research careers, academic inbreeding has been documented in various scientific fields and is often perceived as normal practice in academic culture. In this study, we explored the impact of academic inbreeding on the scientific performance of ecologists. We conducted an online survey to gather information about their mobility, academic age, and publication output regardless of their nationality or institution. Our results show that inbred ecologists publish a deficient number of articles per year, have fewer first-author publications, and are less likely to publish articles with more than 15 authors compared to non-inbred researchers. Although homegrown early career ecologists tend to have more publications, this pattern changes in the senior career stages when non-inbred researchers perform significantly better than their inbred colleagues. These findings suggest that academic inbreeding can negatively impact research careers and scientific output. Raising awareness of this issue may help discourage this practice in academic culture and highlight the importance of mobility and building professional networks outside one’s home institution.
PubDate: 2024-07-16
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- Biotic environment reinforcing the pertinacious clinically relevant
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Abstract: Abstract Immuno-compromised COVID-19 patients being treated with glucocorticoids like Dexamethasone for prolonged periods had led to the surge of mucormycosis. Mucor spores proliferate and spread faster in COVID afflicted persons. In India, more than 51,775 cases and 4300 deaths due to COVID-associated mucormycosis were reported till date. The Government of J&K declared an epidemic of COVID-19 associated mucormycosis under Sect. 2 of the Epidemic Disease Act, 1897. In the backdrop of current COVID scenario, it becomes imperative to study the etiological factors, occurrence of causative agents and aerosolisation of the Mucor spores from the environmental samples leading to mucormycosis. The present study was undertaken to check the presence of Mucor spores in the environment so as to find the reinforcing sources of COVID associated mucormycosis. We isolated three strains of Mucor species: Mucor circinelloides and two Mucor hiemalis species, from environmental samples (air, soil and water), all having a positive relevance to mucormycosis. This is the first study on the presence of mucormycosis causing Mucor species in Kashmir environment. In this study, some pathogenicity marker tests were performed to detect the virulence of these fungal strains such as Anti-fungal susceptibility test (AST), biofilm formation and heat stress test. The in vitro antifungal susceptibility of these species showed the major zone of inhibition by Amphotericin B (Amph) and Nystatin (NS), whereas, Fluconazole (FLC) showed no activity. Biofilm was formed by both Mucor species which was confirmed by crystal violet assay (CV) with positive absorbance readings in microplate reader. Under heat stress, pathogenicity marker test was performed in which both species formed considerable aseptate hyphal growth and small scattered spores. During SEM (Scanning Electron Microscopy) analysis, both the species of Mucor were observed with intact sporangia producing several sporangiospores, whose size dimorphism is linked to its virulence. Thus, augmented knowledge of the epidemiology and clinical presentations of these Mucor species may prevent environmental exposure of immune-compromised patients post-COVID and improve early diagnosis and treatment.
PubDate: 2024-07-12
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- Thermal divergence in a color polymorphic lizard inhabiting contrasting
environments in central Mexico-
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Abstract: Abstract The niche partitioning hypothesis predicts differential use of resources among morphs depending on resource dynamics and morph frequencies. Additionally, morphs might select microhabitats favorable for the regulation of body temperature through behavioral mechanisms. Intra- and intersexual social interactions among morphs can also affect patterns of niche partitioning. Here, we evaluated whether body size, thermal traits (body and environmental temperatures, and behavioral thermoregulation), microhabitat use, and perch height differ among male and female throat color morphs of the lizard Sceloporus grammicus in four different habitat types. Color morphs of both sexes differed in body size, thermal traits, and perch height but not microhabitat use. Lizards of grassland and xeric scrubland were larger, and had greater values of thermal traits but exhibited lower perch height than lizards of mountain cloud forest and pine-oak forest. We found clear evidence of thermal niche partitioning and partial space niche partitioning among color morphs of both sexes of S. grammicus in central Mexico. These results improve our knowledge of the ecology of color polymorphic vertebrate species and show that color morphs of each sex have specific trait combinations to facilitate the use of thermal resources.
PubDate: 2024-07-08
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