Neurological recovery and neurogenesis by curcumin sustained-release system cross-linked with an acellular spinal cord scaffold in rat spinal cord injury: Targeting NLRP3 inflammasome pathway.

In the context of treating spinal cord injury (SCI), the modulation of inflammatory responses, and the creation of a suitable region for tissue regeneration may present a promising approach. This study aimed to evaluate the effects of curcumin (Cur)-loaded bovine serum albumin nanoparticles (Cur-BSA NPs) cross-linked with an acellular spinal cord scaffold (ASCS) on the functional recovery in a rat model of SCI. We developed an ASCS using chemical and physical methods. Cur-BSA, and blank (B-BSA) NPs were fabricated and cross-linked with ASCS via EDC-NHS, resulting in the production of Cur-ASCS and B-ASCS. We assessed the properties of scaffolds and NPs as well as their cross-links. Finally, using a male rat hemisection model of SCI, we investigated the consequences of the resulting scaffolds. The inflammatory markers, neuroregeneration, and functional recovery were evaluated. Our results showed that Cur was efficiently entrapped at the rate of 42% ± 1.3 in the NPs. Compared to B-ASCS, Cur-ASCS showed greater effectiveness in the promotion of motor recovery. The implantation of both scaffolds could increase the migration of neural stem cells (Nestin- and GFAP-positive cells) following SCI with the superiority of Cur-ASCS. Cur-ASCS was successful to regulate the gene expression and protein levels of NLRP3, ASC, and Casp1in the spinal cord lesion. Our results indicate that using ASCS can lead to the entrance of cells into the scaffold and promote neurogenesis. However, Cur-ASCS had greater effects in terms of inflammation relief and enhanced neurogenesis.

Acellular spinal cord scaffold containing quercetin-encapsulated nanoparticles plays an anti-inflammatory role in functional recovery from spinal cord injury in rats.

Inflammatory responses play a crucial role in the pathophysiology of spinal cord injury (SCI) and developing new approaches to establish an anti-inflammatory environment for the promotion of neuroregeneration holds promise as a potential approach. In this study, our aim was to investigate the potential of combining an acellular spinal cord scaffold (ASCS) with quercetin-loaded bovine serum albumin (Qu/BSA) nanoparticles (NPs) for the treatment of SCI. The ASCS was prepared using physical and chemical methods, while the Qu/BSA NPs were prepared through a desolvation technique. The NPs exhibited favorable characteristics, including a mean size of 203 nm, a zeta potential of -38, and an encapsulation efficiency of 96%. Microscopic evaluation confirmed the successful distribution of NPs on the walls of ASCS. Animal studies revealed that Qu/BSA NPs group exhibited a significant decrease in NLRP3, ASC, and Casp1 gene expression compared to the SCI group (p < 0.0001). The findings indicated a significant decrease in the NLRP3, ASC, and Casp1 protein level between the Qu/BSA/ASCS group and the SCI group (p < 0.0001). Moreover, treatment with ASCS containing either blank BSA (B/BSA) NPs or Qu/BSA NPs effectively promoted functional recovery via increasing the amount of nestin- and glial fibrillary acidic protein (GFAP)-positive cells in the site of injury. Notably, Qu/BSA/ASCS exhibited superior outcomes compared to B/BSA/ASCS. Overall, the combination of ASCS with the Qu delivery system presents a promising therapeutic approach for SCI by inhibiting inflammatory responses and promoting neuroregeneration, leading to the restoration of motor function in animals. This study demonstrates the potential of utilizing biomaterials and NPs to enhance the effectiveness of SCI treatment.

Human thumb consists of three phalanges and lacks metacarpal? A morphometric study on the long bones of the hand.

PURPOSE: For many years, it was thought that the thumb consists of just two phalanges that differentiate it from the other four medial triphalangeal fingers. But there are some old reports that few former scientists believed the thumb has three phalanges and it lacked a metacarpal, and the thumb metacarpal is a phalanx. So this anthropometric study was carried out by investigating the morphology of the long bones of the hand and correlations between the thumb metacarpal and other miniature long bones of the hand. METHODS: We studied anterior-posterior X-ray images of the right hands of 80 individuals from 18 to 65 years old. The exploration targets were the length of all metacarpals (MC), proximal phalanges (PP), middle phalanges (MP), and distal phalanges (DP). Friedman Repeated Measures Analysis of Variance and Dunn's post hoc test were carried out to compare the means of all variables. The correlation between all quantitative factors was done by Spearman Rank Correlation (Spearman's Rho) coefficient. RESULTS: Our results showed that the length of the phalanges and the total length of the fingers are independent of the related metacarpal length (P < 0.001). Also, the thumb metacarpal length in comparison to all bones of the hand was significantly different from all long bones of the hand except the proximal phalanx of the middle finger (P = 1). CONCLUSION: Based on the morphology of the long bones of the hand and the high similarity between the thumb metacarpal and phalanges especially the proximal phalanx of the middle finger, it can be suggested that the current thumb metacarpal is a proximal phalanx of the thumb.

Comparing The Effect Of Electroacupuncture And Glibenclamide On Blood Glucose Level And Histological Markers Of Pancreas In Streptozotocin-Induced Diabetic Rats.

BACKGROUND: Diabetes lowers the quality of life and leads to several complications. Glibenclamide is a commonly used step-two treatment in diabetes but it causes weight gain, hypoglycemia and cardiovascular problems. Electroacupuncture (EA) can enhance insulin sensitivity and reduce blood glucose levels. OBJECTIVES: To compare the effects of EA plus glibenclamide (G) with single therapy by G or EA on blood glucose, pancreas volume, islet volume, ratio of islet volume to pancreas volume, apoptotic and beta cells numbers and body weight in diabetic rats. METHODS: Sixty adult male Wistar rats were randomly divided to 10 groups: 2 non-diabetic control groups and 8 diabetic groups (1 control and 7 experimental groups; D/G 2.5, D/G 5, D/G 10 mg/kg, EA, D/EA/G 2.5, D/EA/G 5, and D/EA/G 10). Diabetes was induced by intraperitoneal injection of 35 mg/kg streptozotocin with high-fat diet. At the end of the course, blood samples were obtained and pancreases were dissected. RESULTS: EA was as effective as D/G 5 and D/G 10 in all outcomes. Combination therapy of EA and glibenclamide 5 and 10 mg/kg resulted in a better glucose-lowering effect, greater islet volume and ratio of islet volume to pancreas volume than single therapies (P < .05). EA increased the pancreas volume as much as the combination therapies (P > .05). CONCLUSION: Combination of EA and glibenclamide 5 showed the best effects on blood glucose, islet volume and ratio of islet to pancreas volume. Combination of EA and glibenclamide 2.5 illustrated the best effects on apoptotic and beta cell number of diabetic rats.

Application of non-cooperative dynamic game theory for groundwater conflict resolution.

The opposing objectives of the groundwater stakeholders, ranging from maximum withdrawal for economic gain to minimum withdrawal for aquifer and environmental protection, lead stakeholders to behave non-cooperatively. In this study, dynamic non-cooperative games are applied to model these conflicts. These games incorporate stakeholders' non-cooperative decision-making processes and groundwater exploitation details over time. The two key players considered in this study are the government, which aims to minimize the groundwater drawdown, and local farmers, who pursue maximum economic gain. In order to calculate the players' payoffs over the modeling period, a simulation-optimization model is developed. For evaluation, the proposed methodology is implemented in the Bad-Khaledabad study area in Iran. Therefore, two dynamic non-cooperative games are developed, considering weak governmental power and players' interaction. It is concluded that creating a transactional relationship, involving the cropping patterns changes and the irrigation efficiency enhancement, will increase farmers' profits by 28% and decrease withdrawal from the aquifer by 21%.

The Nonartemisinin Sesquiterpene Lactones Parthenin and Parthenolide Block Plasmodium falciparum Sexual Stage Transmission.

Parthenin and parthenolide are natural products that are closely related in structure to artemisinin, which is also a sesquiterpene lactone (SQL) and one of the most important antimalarial drugs available. Parthenin, like artemisinin, has an effect onPlasmodiumblood stage development. We extended the evaluation of parthenin as a potential therapeutic for the transmissible stages ofPlasmodium falciparumas it transitions between human and mosquito, with the aim of gaining potential mechanistic insight into the inhibitory activity of this compound. We posited that if parthenin targets different biological pathways in the parasite, this in turn could pave the way for the development of druggable compounds that could prevent the spread of artemisinin-resistant parasites. We examined parthenin's effect on male gamete activation and the ookinete-to-oocyst transition in the mosquito as well as on stage V gametocytes that are present in peripheral blood. Parthenin arrested parasite development for each of the stages tested. The broad inhibitory properties of parthenin on the evaluated parasite stages may suggest different mechanisms of action between parthenin and artemisinin. Parthenin's cytotoxicity notwithstanding, its demonstrated activity in this study suggests that structurally related SQLs with a better safety profile deserve further exploration. We used our battery of assays to test parthenolide, which has a more compelling safety profile. Parthenolide demonstrated activity nearly identical to that of parthenin againstP. falciparum, highlighting its potential as a possible transmission-blocking drug scaffold. We discuss the context of the evidence with respect to the next steps toward expanding the current antimalarial arsenal.

Delayed egg hatching of Anopheles gambiae (Diptera: Culicidae) pending water agitation.

Mosquito eggs laid on water surfaces typically hatch spontaneously soon after the embryos within them become fully formed first-instar larvae. However, we have found that Anopheles gambiae Giles, an important vector of malaria in Africa, exhibits delayed hatching until the water surface is agitated, a feature overlooked in most laboratory colonies. Agitation within 24 h postoviposition, before embryonation was complete, failed to stimulate delayed postembryonic hatching of isolated eggs on the following day (day 2), when < 1% had hatched spontaneously. However, 5 min of water agitation of these dormant pharate first-instar larvae on day 2 resulted in an almost immediate hatch of 63.3 versus 0% of nonagitated controls, plus another 3.9 versus 0.3%, respectively, during the following 24 h. With daily agitation, installment hatching occurred mainly during 2-6 d postoviposition. The mean cumulative hatch after 7 d of daily agitation was 83.1 versus 1.1% of nonagitated eggs. Experiments with eggs in groups demonstrated that egg density and activity of already-hatched larvae had no stimulatory effect. Eggs stored 1-4 wk at 25.5 or at 15.5 degrees C, and then agitated daily for 6 d at 25.5 degrees C, showed a gradual decline in viability. Viability was sustained longer at the lower temperature. Implications of agitation-induced egg hatching for rainy-season and dry-season ecology of An. gambiae are discussed. Suspended hatching and cool storage already are proving convenient for efficient mass rearing and accurate modeling of weather-based population dynamics.

Odor-evoked transcriptomics of Aedes aegypti mosquitoes.

Modulation of odorant receptors mRNA induced by prolonged odor exposure is highly correlated with ligand-receptor interactions in Drosophila as well as mammals of the Muridae family. If this response feature is conserved in other organisms, this presents an intriguing initial screening tool when searching for novel receptor-ligand interactions in species with predominantly orphan olfactory receptors. We demonstrate that mRNA modulation in response to 1-octen-3-ol odor exposure occurs in a time- and concentration-dependent manner in Aedes aegypti mosquitoes. To investigate gene expression patterns at a global level, we generated an odor-evoked transcriptome associated with 1-octen-3-ol odor exposure. Transcriptomic data revealed that ORs and OBPs were transcriptionally responsive whereas other chemosensory gene families showed little to no differential expression. Alongside chemosensory gene expression changes, transcriptomic analysis found that prolonged exposure to 1-octen-3-ol modulated xenobiotic response genes, primarily members of the cytochrome P450, insect cuticle proteins, and glucuronosyltransferases families. Together, these findings suggest that mRNA transcriptional modulation of olfactory receptors caused by prolonged odor exposure is pervasive across taxa and can be accompanied by the activation of xenobiotic responses.

Pathophysiology and diagnosis of diabetic retinopathy: a narrative review.

Diabetes is an endocrine disorder which is known by abnormal high blood glucose levels. There are two main categories of diabetes: type I (10%-15%) and type II (85%-90%). Although type II is more common, type I is the most common form in children. Diabetic retinopathy (DR), which remains the foremost cause of losing vision in working-age populations, can be considered as the main complication of diabetes mellitus. So choosing the best method for diagnosing, tracking, and treating the DR is vital to enhance the quality of life and decrease the medical expenses. Each method for diagnosing DR has some advantages and the best way must be selected according to the points that we need to find. For writing this manuscript, we made a list of relevant keywords including diabetes, DR, pathophysiology, ultrawide field imaging, fluorescein angiography, optical coherence tomography, and optical coherence tomography-angiography, and then we started searching for studies in PubMed, Scopus, and Web of Science databases. This review article covers the pathophysiology of DR and medical imaging techniques to monitor DR. First, we introduce DR and its pathophysiology and then we present the medical imaging techniques to monitor it.

Odor-evoked transcriptomics of Aedes aegypti mosquitoes.

Modulation of odorant receptors mRNA induced by prolonged odor exposure is highly correlated with ligand-receptor interactions in Drosophila as well as mammals of the Muridae family. If this response feature is conserved in other organisms, this presents a potentially potent initial screening tool when searching for novel receptor-ligand interactions in species with predominantly orphan olfactory receptors. We demonstrate that mRNA modulation in response to 1-octen-3-ol odor exposure occurs in a time- and concentration-dependent manner in Aedes aegypti mosquitoes. To investigate gene expression patterns at a global level, we generated an odor-evoked transcriptome associated with 1-octen-3-ol odor exposure. Transcriptomic data revealed that ORs and OBPs were transcriptionally responsive whereas other chemosensory gene families showed little to no differential expression. Alongside chemosensory gene expression changes, transcriptomic analysis found that prolonged exposure to 1-octen-3-ol modulated xenobiotic response genes, primarily members of the cytochrome P450, insect cuticle proteins, and glucuronosyltransferases families. Together, these findings suggest that mRNA transcriptional modulation caused by prolonged odor exposure is pervasive across taxa and accompanied by the activation of xenobiotic responses. Furthermore, odor-evoked transcriptomics create a potential screening tool for filtering and identification of chemosensory and xenobiotic targets of interest.

Analysis and optimization of a synthetic milkweed floral attractant for mosquitoes.

A pentane extract of flowers of common milkweed, Asclepias syriaca (Asclepiadaceae), elicited significant orientation from both male and female Culex pipiens in a dual-port flight olfactometer. Analysis of the extract by gas chromatography-mass spectrometry revealed six major constituents in order of relative abundance: benzaldehyde, (E)-ß-ocimene, phenylacetaldehyde, benzyl alcohol, nonanal, and (E)-2-nonenal. Although not all were collected from the headspace profile of live flowers, a synthetic blend of these six compounds, when presented to mosquitoes in the same levels and proportions that occur in the extract, elicited a response comparable to the extract. Subtractive behavioral bioassays demonstrated that a three-component blend consisting of benzaldehyde, phenylacetaldehyde, and (E)-2-nonenal was as attractive as the full blend. These findings suggest the potential use of synthetic floral-odor blends for monitoring or control of both male and female disease-vectoring mosquitoes.

Attraction of the Mosquitoes Aedes aegypti and Aedes albopictus (Diptera: Culicidae) to a 3-Part Phytochemical Blend in a Mesocosm.

Aedes aegypti (L.) and Aedes albopictus (Skuse) mosquitoes of both sexes were attracted to a 3-part volatile synthetic phytochemical blend but differed according to their component ratios, 7:3:2 or 1:1:1, and their initial concentrations. These arbovirus vectors were presented with the blends as baits in paired baited and blank CFG traps in a large greenhouse mesocosm. Ae. aegypti attraction was highest at a 7:3:2 blend ratio, but at a concentration half that found most effective for an anopheline mosquito species in outdoor screenhouses. Both lower and higher concentrations yielded substantially lower attraction scores for Ae. aegypti. By contrast, the few tests conducted on Ae. albopictus showed that it was not as sensitive to concentration, but again it was more responsive to the 7:3:2 ratio of components than to the 1:1:1 ratio. The two sexes of both species were represented equally in the trap catches, indicating the potential value of this and similar attractive blends for population surveillance and control of Aedes mosquitoes.

Formation and activity of NLRP3 inflammasome and histopathological changes in the lung of corpses with COVID-19.

COVID-19 is a contagious disease that attacks many organs but the lungs are the main organs affected. The inflammasome activation results in the exacerbation of inflammatory response in infectious disease. The aim of this study is to investigate the formation and activity of the NLRP3 inflammasome complex and the histopathological changes caused by the coronavirus in the lung of deceased persons with COVID-19. In total, 10 corpses; 5 corpses with no history of any infectious diseases and COVID-19 and 5 corpses with the cause of death of COVID-19 were included in this study. Lung tissue samples were harvested during autopsy under safe conditions. Fresh tissues in each group were used to measure the genes expression and proteins level of NLRP3, ASC, Caspase-1, IL-1ß, IL-6 and TNF-α and a routine hematoxylin and eosin staining was performed for histological assessment. Data are represented as the means ± SD. Statistical significance difference was accepted at a p-value less than 5%. The NLRP3, ASC, Caspase-1, IL-1ß, IL-6 and TNF-α genes expression and proteins level were elevated in the lung of the COVID-19 group in comparison with the control group. Histological findings presented the increasing number of polymorphonuclear leukocytes, macrophages and also pulmonary fibrosis in the lungs of corpses with the cause of death of COVID-19. High expression of NLRP3 inflammasome components and its relation with the pathophysiology of the coronavirus-infected lung suggested that targeting the NLRP3 inflammasome could be helpful in achieving a more effective treatment in patients with COVID-19.

Sex steroids-induced neurogenesis in adult brain: a better look at mechanisms and mediators.

Adult neurogenesis is the production of new nerve cells in the adult brain. Neurogenesis is a clear example of the neuroplasticity phenomenon which can be observed in most of mammalian species, including human beings. This phenomenon occurs, at least, in two regions of the brain: the subgranular zone of the dentate gyrus in hippocampus and the ventricular zone of lateral ventricles. Numerous studies have investigated the relationship between sex steroid hormones and neurogenesis of adult brain; of which, mostly concentrated on the role of estradiol. It has been shown that estrogen plays a significant role in this process through both classic and non-classic mechanisms, including a variety of different growth factors. Therefore, the objective of this review is to investigate the role of female sex steroids with an emphasis on estradiol and also its potential implications for regulating the neurogenesis in the adult brain.

Novel three-dimensional biochip pulmonary sarcoidosis model.

Sarcoidosis is a multi-system disorder of granulomatous inflammation which most commonly affects the lungs. Its etiology and pathogenesis are not well defined in part due to the lack of reliable modeling. Here, we present the development of an in vitro three-dimensional lung-on-chip biochip designed to mimic granuloma formation. A lung on chip fluidic macrodevice was developed and added to our previously developed a lung-on-membrane model (LOMM). Granulomas were cultured from blood samples of patients with sarcoidosis and then inserted in the air-lung-interface of the microchip to create a three-dimensional biochip pulmonary sarcoidosis model (3D BSGM). Cytokines were measured after 48 hours. ELISA testing was performed to measure cytokine response difference between LOMM with 3D BSGM. There were statistically significant differences in IL-1ß (P = 0.001953), IL-6 (P = 0.001953), GM-CSF (P = 0.001953), and INF-γ expressions (P = 0.09375) between two groups. The current model represents the first 3D biochip sarcoidosis model created by adding a microfluidics system to a dual-chambered lung on membrane model and introducing developed sarcoid-granuloma to its air-lung-interface.

Effects of illicit drugs on structural and functional impairment of testis, endocrinal disorders, and molecular alterations of the semen.

Illicit drug use is growing among young people, which is one of the major problems in today's society that can be associated with many medical issues, including infertility. Amphetamines, cocaine, opioids, and marijuana are the most common and the most used illicit drugs worldwide. The purpose of this review was to collect as much literature as possible about the impact of illicit drugs on male fertility and summarize their valuable data. Original studies and reviews were collected by searching the keywords "illicit drugs (all kinds of that) and male infertility". The obtained information was also categorized based on the content of the "Infertility in the Male" book. Almost all studies suggested that taking all kinds of illicit drugs with the effects on different parts of the male reproductive system can result in subfertility or complete infertility in the consumers. Although the data in this field are not decisive and there are some confounding factors in human studies, it can be inferred that the use of any illicit drug with an effect on male sexual health reduces fertility potency. Therefore, it is recommended that couples, who are planning to conceive, avoid taking any illicit drugs before and during treatment.

Biomedical features of flaxseed against different pathologic situations: A narrative review.

Flaxseed is a plant that grows and is cultivated in more than 50 countries; the main flax producer countries are Canada, China, the United States, and India. The purpose of the present study was to overview the source, chemical compounds, and mechanisms of the therapeutic effects of this valuable plant. For writing this manuscript, we made a list of relevant keywords and phrases, and then we started searching for studies in PubMed, Scopus, and Web of Science databases. The main constituents of flaxseed include lipids, proteins, lignans, fibers, and minerals. Flaxseed is full of antioxidants such as tocopherols, betacarotene, cysteine, and methionine which result in a decrease in blood pressure, heart disease, hepatic and neurological disorders, and increased insulin sensitivity. Flaxseed is commonly used for its antidiabetic and anticancer activities and also it is beneficial for cardiovascular, gastrointestinal, hepatic, urological, and reproductive disorders, and because of these beneficial effects, it is recognized as a medical plant.

COVID-19 and multiorgan failure: A narrative review on potential mechanisms.

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) in December 2019 form Wuhan, China leads to coronavirus disease 2019 (COVID-19) pandemic. While the common cold symptoms are observed in mild cases, COVID-19 is accompanied by multiorgan failure in severe patients. The involvement of different organs in severe patients results in lengthening the hospitalization duration and increasing the mortality rate. In this review, we aimed to investigate the involvement of different organs in COVID-19 patients, particularly in severe cases. Also, we tried to define the potential underlying mechanisms of SARS-CoV2 induced multiorgan failure. The multi-organ dysfunction is characterized by acute lung failure, acute liver failure, acute kidney injury, cardiovascular disease, and as well as a wide spectrum of hematological abnormalities and neurological disorders. The most important mechanisms are related to the direct and indirect pathogenic features of SARS-CoV2. Although the presence of angiotensin-converting enzyme 2, a receptor of SARS-CoV2 in the lung, heart, kidney, testis, liver, lymphocytes, and nervous system was confirmed, there are controversial findings to about the observation of SARS-CoV2 RNA in these organs. Moreover, the organ failure may be induced by the cytokine storm, a result of increased levels of inflammatory mediators, endothelial dysfunction, coagulation abnormalities, and infiltration of inflammatory cells into the organs. Therefore, further investigations are needed to detect the exact mechanisms of pathogenesis. Since the involvement of several organs in COVID-19 patients is important for clinicians, increasing their knowledge may help to improve the outcomes and decrease the rate of mortality and morbidity.

Trigonella foenum-graceum seed (Fenugreek) hydroalcoholic extract improved the oxidative stress status in a rat model of diabetes-induced memory impairment.

Background The antidiabetic and antioxidant effects of Trigonella foenum-graceum have been suggested. The effects of hydroalcoholic extract of the plant seeds and metformin against the diabetes-induced memory impairment were investigated. Materials and methods The rats were treated: (1) control, (2) diabetic (3-6) and diabetic rats treated by 50, 100 and 200 mg/kg of the plant extract or metformin. The rats were diabetic by streptozotocin (STZ, 55 mg/kg). After the passive avoidance test, malondialdehyde (MDA), nitric oxide (NO) metabolites, total thiol (SH), catalase (CAT) and superoxide dismutase (SOD) were determined in the brain. Results In the diabetic group, at 3, 24 and 48 h after receiving a shock, the latency to enter the dark room was lower than for the controls (p < 0.001). All doses of the extract and metformin increased the latencies to enter the dark at 3 and 24 h after the shock treatment (p < 0.05-p < 0.001). Additionally, the two higher doses of the extract and metformin increased the latency at 48 h after the shock (p < 0.05-p < 0.001). Diabetes also elevated MDA and NO metabolites, while it reduced thiol, SOD and CAT in the hippocampal and cortical tissues (p < 0.001). Treatment of the diabetic animals by the highest dose of the extract and also metformin reduced the MDA and NO metabolites, while it improved thiols, SOD and CAT (p < 0.01-p < 0.001). Conclusions Based on our findings, metformin and the hydro-alcoholic extract from the T. foenum-graceum seed prevented memory deficits resulting from diabetes. Preventing oxidative damage in the brain may at least, in part, be responsible for the positive effects of the extract and metformin.

Alteration of plant species assemblages can decrease the transmission potential of malaria mosquitoes.

Knowledge of the link between a vector population's pathogen-transmission potential and its biotic environment can generate more realistic forecasts of disease risk due to environmental change. It also can promote more effective vector control by both conventional and novel means.This study assessed the effect of particular plant species assemblages differing in nectar production on components of the vectorial capacity of the mosquito Anopheles gambiae s.s., an important vector of African malaria.We followed cohorts of mosquitoes for three weeks in greenhouse mesocosms holding nectar-poor and nectar-rich plant species by tracking daily mortalities and estimating daily biting rates and fecundities. At death, a mosquito's insemination status and wing length were determined. These life history traits allowed incorporation of larval dynamics into a vectorial capacity estimate. This new study provided both novel assemblages of putative host plants and a human blood host within a nocturnal period of maximum biting.Survivorship was significantly greater in nectar-rich environments than nectar-poor ones, resulting in greater total fecundity. Daily biting rate and fecundity per female between treatments was not detected. These results translated to greater estimated vectorial capacities in the nectar-rich environment in all four replicates of the experiment (means: 1,089.5 ± 125.2 vs. 518.3 ± 60.6). When mosquito density was made a function of survival and fecundity, rather than held constant, the difference between plant treatments was more pronounced, but so was the variance, so differences were not statistically significant. In the nectar-poor environment, females' survival suffered severely when a blood host was not provided. A sugar-accessibility experiment confirmed that Parthenium hysterophorus is a nectar-poor plant for these mosquitoes.Synthesis and applications. This study, assessing the effect of particular plant species assemblages on the vectorial capacity of malaria mosquitoes, highlights the likelihood that changes in plant communities (e.g. due to introduction of exotic or nectar-rich species) can increase malaria transmission and that a reduction of favourable nectar sources can reduce it. Also, plant communities' data can be used to identify potential high risk areas. Further studies are warranted to explore how and when management of plant species assemblages should be considered as an option in an integrated vector management strategy.