Botulinum toxin type A in treating early-stage patients with small-angle acute acquired comitant esotropia

AIM:To investigate botulinum toxin A(BTXA)efficacy on small-angle(≤25Δ)acute acquired concomitant esotropia(AACE)in early-stage patients.METHODS:The electronic medical record data of AACE patients during March 2019 and June 2023 were collected in this retrospective and hospital-based cohort study.A total of 72 small-angle AACE patients received BTXA extraocular muscle injection.Patients were grouped by onset-to-treatment time(Group A:≤6mo,Group B:>6mo).Deviation of esotropia,eye alignment and stereopsis were analyzed at the period of pre/post-injection(1wk,1,3,and 6mo).Orthophoria rate at 6mo(horizontal deviation<10Δand binocular single vision)were considered as outcome index.RESULTS:There were no significant baseline differences(P>0.05)between two groups except onset-to-treatment time(2mo vs 11mo,P<0.001).Higher orthophoria rates were in Group A at last follow-up(94.74%vs 73.53%,P=0.013).Post-BTXA deviations of two groups at 1mo showed no difference(P>0.05);while in 3 and 6mo Group A was significantly smaller than group B(all P<0.001).No statistically significant differences were observed among all post-BTXA deviations of near and distance in Group A.In Group B,deviation at 3mo(near:2Δvs 0,P<0.001;distance:4Δvs 0,P<0.001)and 6mo(near:6Δvs 0,P<0.001;distance:6Δvs 0,P<0.001)was significant increased compared to deviation at 1wk after treatment.Group A showed better stereopsis recovery in last follow-up compared to Group B(80″vs 200″,P=0.002).Both groups obtained improved stereopsis after treatment(Group A:80″vs 300″,P<0.001;Group B:200″vs 300″,P=0.037).CONCLUSION:BTXA is effective for AACE with small deviation(≤25Δ)in early stage.Delayed treatment(>6mo)may reduce BTXA efficacy.Early BTXA intervention benefits long-term eye alignment and stereopsis recovery.

Botulinum toxin type A-targeted SPP1 contributes to neuropathic pain by the activation of microglia pyroptosis

BACKGROUND Neuropathic pain(NP)is the primary symptom of various neurological condi-tions.Patients with NP often experience mood disorders,particularly depression and anxiety,that can severely affect their normal lives.Microglial cells are as-sociated with NP.Excessive inflammatory responses,especially the secretion of large amounts of pro-inflammatory cytokines,ultimately lead to neuroinflam-mation.Microglial pyroptosis is a newly discovered form of inflammatory cell death associated with immune responses and inflammation-related diseases of the central nervous system.METHODS Two models,an in vitro lipopolysaccharide(LPS)-stimulated microglial cell model and a selective nerve injury model using BTX-A and SPP1 knockdown treatments,were used.Key proteins in the pyroptosis signaling pathway,NLRP3-GSDMD,were assessed using western blotting,real-time quantitative polymerase chain reaction,and immunofluorescence.Inflammatory factors[interleukin(IL)-6,IL-1β,and tumor necrosis factor(TNF)-α]were assessed using enzyme-linked immuno-sorbent assay.We also evaluated microglial cell proliferation and apoptosis.Furthermore,we measured pain sensation by assessing the delayed hind paw withdrawal latency using thermal stimulation.RESULTS The expression levels of ACS and GSDMD-N and the mRNA expression of TNF-α,IL-6,and IL-1βwere enhanced in LPS-treated microglia.Furthermore,SPP1 expression was also induced in LPS-treated microglia.Notably,BTX-A inhibited SPP1 mRNA and protein expression in the LPS-treated microglia.Additionally,depletion of SPP1 or BTX-A inhibited cell viability and induced apoptosis in LPS-treated microglia,whereas co-treatment with BTX-A enhanced the effect of SPP1 short hairpin(sh)RNA in LPS-treated microglia.Finally,SPP1 depletion or BTX-A treatment reduced the levels of GSDMD-N,NLPRP3,and ASC and suppressed the production of inflammatory factors.CONCLUSION Notably,BTX-A therapy and SPP1 shRNA enhance microglial proliferation and apoptosis and inhibit microglial death.It improves pain perception and inhibits microglial activation in rats with selective nerve pain.

Betulinic acid protects against ovarian impairment by decreasing F-2 toxin-induced oxidative stress and inflammation associated with the downregulation of p38 expression in mice

F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in animals.Betulinic acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological activities.In this study,the antioxidative and anti-inflammatory effects of BA and its underlying mechanism are explored in F-2 toxin-triggered mouse ovarian damage.We found that BA alleviated the F-2 toxin-induced ovarian impairment by stimulating follicle growth,reducing inflammatory cell infiltration,repairing damaged mitochondria and endoplasmic reticulum.Simultaneously,BA not only reversed F-2 toxin-induced reduction of follicle stimulating hormone(FSH)and luteinizing hormone(LH)levels in the serum,but also restrained the protein expression of the estrogen receptors a(ERa)and ERβ.Moreover,BA restored the balance of F-2 toxin-induced ovarian redox system disorders.Subsequently,we found that 0.25 mg/kg BA played an anti-inflammatory role in the F-2 toxin-induced ovarian impairment by decreasing interleukin-1β(IL-1β).IL-6,and tumor necrosis factor-α(TNF-α)mRNA expression,as well as inhibiting p38 protein expression.These data demonstrated that BA exerts its protective effect on F-2 toxin-induced ovarian oxidative impairment and inflammation by inhibiting p38 expression,which implies a natural product-based medicine to ameliorate F-2 toxin-caused female reproductive toxicity and provides a detoxifying method for food contaminated by mycotoxin.

Clinical effect of botulinum toxin type A combined with autologous fat grafting in patients with nasolabial fold depression

BACKGROUND Nasolabial fold(NLF)depression can affect the facial appearance of patients to some extent and increase their psychological burdens.In recent years,autologous fat grafting(AFG)combined with botulinum toxin A(BTX-A)injection(AFG+BTX-A injection)has been gradually applied in the treatment of patients with NLF depression.Although studies have been conducted on the efficacy and safety of AFG+BTX-A injection in treating NLF depression,the experimental design,observational indicators,and sample enrollment criteria vary remarkably,making it difficult to draw convincing and consistent conclusions.Thus,further relevant research is warranted.AIM To assess the esthetic improvement,efficacy,and safety of AFG+BTX-A injections in patients with NLF depression.METHODS This study included 60 patients with NLF depression who were treated in our hospital from February 2019 to April 2021.These patients were categorized into control(n=30)and observation(n=30)groups.The observation group received AFG+BTX-A injection,whereas the control group underwent AFG only.All patients were evaluated using the wrinkle severity rating scale(WSRS)and global aesthetic improvement scale.The compactness of facial contours,skin evaluation indexes,adverse reactions,and satisfaction of the two groups were evaluated 3 months postoperatively.RESULTS The WSRS scores of the observation group at 1,3,and 6 months postoperatively were lower than those of the control group(P<0.05).Three months postoperatively,facial fine lines and pores showed obvious improvement and the skin index score was higher in the observation group than in the control group(P<0.05).The compactness of facial contours was better in the observation group than in the control group(P<0.05).In addition,no remarkable differences were noted in the incidence of postoperative adverse reactions such as facial stiffness,facial asymmetry,facial bruising,and facial concavity inequality(P>0.05).CONCLUSION AFG+BTX-A injection is a highly safe,cost-effective,effective,and long-lasting treatment for NLF depression with high esthetic value,which should be promoted in the future.

Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins

Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies.

Botulinum toxin type A injection combined with biofeedback in the treatment of spastic pelvic floor syndrome

BACKGROUND Spastic pelvic floor syndrome(SPFS)is a refractory pelvic floor disease characterized by abnormal(uncoordinated)contractions of the external anal sphincter and puborectalis muscle during defecation,resulting in rectal emptation and obstructive constipation.The clinical manifestations of SPFS are mainly characterized by difficult defecation,often accompanied by a sense of anal blockage and drooping.Manual defecation is usually needed during defecation.From physical examination,it is commonly observed that the patient's anal muscle tension is high,and it is difficult or even impossible to enter with his fingers.AIM To investigate the characteristics of anorectal pressure and botulinum toxin A injection combined with biofeedback in treating pelvic floor muscle spasm syndrome.METHODS Retrospective analysis of 50 patients diagnosed with pelvic floor spasm syndrome.All patients underwent pelvic floor surface electromyography assessment,anorectal dynamics examination,botulinum toxin type A injection 100 U intramuscular injection,and two cycles of biofeedback therapy.RESULTS After the botulinum toxin A injection combined with two cycles of biofeedback therapy,the patient's postoperative resting and systolic blood pressure were significantly lower than before surgery(P<0.05).Moreover,the electromyography index of the patients in the resting stage and post-resting stages was significantly lower than before surgery(P<0.05).CONCLUSION Botulinum toxin A injection combined with biofeedback can significantly reduce pelvic floor muscle tension in treating pelvic floor muscle spasm syndrome.Anorectal manometry is an effective method to evaluate the efficacy of treatment objectively.However,randomized controlled trials are needed.

Botulinum toxin type A for treating chronic low back pain:A double blinded randomized control study

BACKGROUND Low back pain(LBP)is a prevalent issue that orthopedic surgeons frequently address in the outpatient setting.LBP can arise from various causes,with stiffness in the paraspinal muscles being a notable contributor.The administration of Botulinum toxin type A(BoNT-A)has been found to alleviate back pain by relaxing these stiff muscles.While BoNT-A is approved for use in numerous conditions,a limited number of randomized clinical trials(RCTs)validate its efficacy specifically for treating LBP.AIM To study the safety and the efficacy of BoNT-A in minimizing pain and improving functional outcomes in patients of chronic LBP(CLBP).METHODS In this RCT,adults aged 18-60 years with mechanical LBP persisting for at least six months were enrolled.Participants were allocated to either the Drug group,receiving 200 Ipsen Units(2 mL)of BoNT-A,or the Control group,which received a 2 mL placebo.Over a 2-month follow-up period,both groups were assessed using the Visual Analog Scale(VAS)for pain intensity and the Oswestry Disability Index(ODI)for disability at the start and conclusion of the study.A decrease in pain by 50%was deemed clinically significant.RESULTS The study followed 40 patients for two months,with 20 in each group.A clinically significant reduction in pain was observed in 36 participants.There was a statistically significant decrease in both VAS and ODI scores in the groups at the end of two months.Nonetheless,when comparing the mean score changes,only the reduction in ODI scores(15 in the placebo group vs 16.5 in the drug group,clinically insignificant)was statistically significant(P=0.012),whereas the change in mean VAS scores was not significant(P=0.45).CONCLUSION The study concludes that BoNT-A does not offer a short-term advantage over placebo in reducing pain or improving LBP scores in CLBP patients.

完美音浪——法拉利12CILINDRI SPIDER

近日,法拉利12Cilindri Spider在迈阿密海滩上的一场独家活动上亮相。作为一款设计理念承袭自20世纪50与60年代法拉利Gran Turismo敞篷车的新款车型,该车将公路赛车无与伦比的性能、12缸发动机声浪以及长途驾驶舒适性结合在一起,并在设计上打破了法拉利双座berlinetta Spider跑车一贯的肌肉感,采用了一种更加未来主义、建立在纯粹形式基础上的设计语言。

Severe Botulism after Intragastric Botulinum Toxin-A Injection: A Case Series

Intragastric botulismus toxin-A (BoNT-A) is one of the new approaches in the treatment of obesity. We aimed to contribute to the literature by presenting the clinical features, laboratory findings and treatment responses of iatrogenic botulism cases due to intragastric BoNT-A administered in our clinic. All detailed medical information was obtained by accessing the medical records of the patients who were hospitalized and followed up and treated between September 2022 and December 2022, and the diagnosis of A.05.1 Botulism was entered according to ICD-10, and whose clinical findings were compatible with botulism disease and who underwent intragastric BoNT-A application beforehand. These records were obtained by examining this information. 10 patients who developed botulism after intragastric BoNT-A application between 01/09/2022 and 28/02/2023 were followed up in our clinic. All of the patients were women. The mean age was 35. The mean hospital stay was 9 days. Only 1 of our cases required intensive care. Good response to treatment was accepted as a complete or near-complete improvement in the clinical findings of the patients and all of them had a good response to treatment. Intragastric BoNT-A administration is a procedure that requires careful indication with a profit/loss calculation considering the potential side effects. In addition, attention should be paid to dilution rates and dose amounts.

Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers(Ostrinia furnaealis) and Spiders(Xysticus ephippiatus)

Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer （ACB） larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore, randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin＇s efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application.

A Mechanical Model for the Adhesion of Spiders to Nominally Flat Surfaces

In dry attachment systems of spiders and geckos, van der Waals forces mediate attraction between substrate and animal tarsus. In particular, the scopula of Evarcha arcuata spiders allows for reversible attachment and easy detachment to a broad range of surfaces. Hence, reproducing the scopula's roughness compatibility while maintaining anti-bunching features and dirt particle repellence behavior is a central task for a biomimetic transfer to an engineered model. In the present work we model the scopula of E. arcuata from a mechano-elastic point of view analyzing the influence of its hierarchical structure on the attachment behavior. By considering biological data of the gecko and spider, and the simulation results, the adhesive capabilities of the two animals are compared and important confirmations and new directives in order to reproduce the overall structure are found. Moreover, a possible suggestion of how the spider detaches in an easy and fast manner is proposed and supported by the results.

General mechanism of spider toxin family I acting on sodium channel Nav1.7

Various peptide toxins in animal venom inhibit voltage-gated sodium ion channel Nav1.7, including Nav-targeting spider toxin(NaSpTx) Family I. Toxins in NaSpTx Family I share a similar structure, i.e., Nterminal, loops 1–4, and C-terminal. Here, we used Mu-theraphotoxin-Ca2a(Ca2a), a peptide isolated from Cyriopagopus albostriatus, as a template to investigate the general properties of toxins in NaSpTx Family I. The toxins interacted with the cell membrane prior to binding to Nav1.7 via similar hydrophobic residues. Residues in loop 1, loop 4,and the C-terminal primarily interacted with the S3–S4 linker of domain II, especially basic amino acids binding to E818. We also identified the critical role of loop 2 in Ca2a regarding its affinity to Nav1.7.Our results provide further evidence that NaSpTx Family I toxins share similar structures and mechanisms of binding to Nav1.7.

Predatory Efficacy of Cotton Inhabiting Spiders on Bemisiatabaci, Amrascadevastans Thripstabaci and Helicoverpa armigera in Laboratory Conditions

Distinction of predator＇s diet and prey choice preference is a hot topic of current investigations. Spider being generalist predator and cosmopoliter in nature acts as biological control agent in many agro-ecosystems. In the current study, predatory efficacy of five spiders （Pardosa birmanica, Cyclosa insulana, Thomisus projectus, Plexippus paykulli and Lycosa terrestris） inhabiting the cotton fieldevaluated in the laboratory conditions maintained at （27＋2）℃ temperature, 65%-5% relative humidity and 12 ： 12 h of light and dark photoperiod. Four key cotton pests＇ viz. Bemisiatabaci, Amrascaderastans Thripstabaci and Helicoverpa armigera were utilized in the choice and no-choice predatory studies. The findings of current investigation revealed that each predatory spider utilized at least one pest species. Predation rate was found higher in the no-choice predation because of unavailability of substitutes feeding source. The investigation also indicated each predatory spider killed more pests than consumed. The findings of this study support the predatory role of spiders in controlling the cotton major pests.

Comparative transcriptomics highlights convergent evolution of energy metabolic pathways in group-living spiders

Although widely thought to be aggressive, solitary,and potentially cannibalistic, some spider species have evolved group-living behaviors. The distinct transition provides the framework to uncover groupliving evolution. Here, we conducted a comparative transcriptomic study and examined patterns of molecular evolution in two independently evolved group-living spiders and twelve solitary species. We report that positively selected genes among groupliving spider lineages are significantly enriched in nutrient metabolism and autophagy pathways. We also show that nutrient-related genes of group-living spiders convergently experience amino acid substitutions and accelerated relative evolutionary rates. These results indicate adaptive convergence of nutrient metabolism that may ensure energy supply in group-living spiders. The decelerated evolutionary rate of autophagy-related genes in group-living lineages is consistent with an increased constraint on energy homeostasis as would be required in a group-living environment. Together, the results show that energy metabolic pathways play an important role in the transition to group-living in spiders.

Predator perception of detritus and eggsac decorations spun by orb-web spiders Cyclosa octotuberculata:Do they function to camouflage the spiders?

Camouflage is one of the most widespread and powerful strategies that animals use to make detection/recognitionmore difficult. Many orb-web spiders of the genus Cyclosa add prey remains, plant debris, moults, and/or eggsacs to their webscalled web decorations. Web decorations resembling spider body colour pattern have been considered to camouflage the spiderfrom predators. While this camouflage is obvious from a human's perspective, it has rarely been investigated from a predator'sperspective. In this study, we tested the visibility of web decorations by calculating chromatic and achromatic contrasts of detritusand eggsac decorations built by Cyclosa octotuberculata, against four different backgrounds viewed by both bird (e.g., blue tits)and hymenopteran (e.g. wasps) predators. We showed that both juvenile and adult spiders on webs with detritus or egg-sac decorationswere undetectable by both hymenopteran and bird predators over short and long distances. Our results thus suggest thatdecorating webs with detritus or eggsacs by C. octotuberculata may camouflage the spiders from both hymenopteran and birdpredators in their common habitats [Current Zoology 56 (3): 379-387, 2010].

Antimicrobial Activity of Purified Toxins from Crossopriza lyoni (Spider) against Certain Bacteria and Fungi

Toxins from spider venom Crossopriza lyoni were subjected to purify on a Sepharose CL-6B 200 column. These were investigated for its antibacterial and antifungal activity against 13 infectious microbial pathogenic strains. Antimicrobial susceptibility was determined by using paper disc diffusion and serial micro-dilution assays. Triton X-100 (0.1%) proved to be a good solubilizing agent for toxin/proteins. Higher protein solubilization was observed in the supernatant than in the residue, except TCA. The elution pattern of purified and homogenized sting glands displayed two major peaks at 280 nm. First one was eluted in fraction no. 43 - 51 while second one after fraction no. 61 - 90. From gel filtration chromatography total yield of protein obtained was 67.3%. From comparison of gel chromatographs eluted toxins peptide molecular weight was ranging from 6.2 - 64 kD. Toxin peptides have shown lower MIC values i.e. 7.5 - 15 μg/ml against K. pneumoniae, E. coli, L. acidophilus, B. cereus;against S. aureus and M. luteus that the broad spectrum antibiotics i.e. tetracycline and ampicillin. In tests, larger inhibition zone diameter was obtained in comparison to control. Diameter of inhibition zones obtained in spider toxins at a concentration range of 197.12 - 0.96 g/ml for E. coli was 17.86 ± 0.21, Bacillus cereus 19.13 ± 0.21, L. acidophilus 16.83 ± 0.25, Micrococcus luteus 18.46 ± 0.17, S. aeurus 16.23 ± 0.19, Klebsiella pneumoniae 21.83 ± 0.16, Salmonella typhi 16.16 ± 0.21, Vibrio cholera 18.66 ± 0.21, Pseudomonas aeruginosa 18.66 ± 0.21, Aspergillus niger 22.9 ± 0.24, Candida albicans 24.66 ± 0.28, Rhizopus stolonifer 21.1 ± 0.16. Spider toxins generate cytotoxic effect on bacterial cells that results in heavy cell death. No doubt spider toxins can be used as alternate of broad spectrum antibiotics.

Investigation on Species of Spiders in Tea Plantations in Enshi Region of China

The spider resources in tea plantations in Enshi region have been investigated and 51 species of spiders belonging to 22 families have been identified in the paper. The dominant species are clarified and their directory and distribution status are also listed in the paper.

Species Investigation and Population Dynamic of Spiders in Tea Gardens in Northern Guangxi

A systematic investigation on spiders in a tea garden of Guilin Institute of Tea Sciences was conducted. The results showed that totally 687 specimens were collected, belonging to 34 species, 27genera, 14 families, 2 suborders, and a new record species Trochosa suiningensis in Guangxi was found. Spider is a ma- jor developing natural enemy group of insect pests in tea garden, with features of wide distribution, large quantity, long duration, strong predatory and stress resist- ance, which has strong predation on adults and nymphs of Empoasca vitis and young larvae of Ectropis oblique. The population of spiders in tea garden significantly increases after middle June, and reaches the peak in July and August every year.

The Predatory Function of Three Spiders to Two Insect Pests in Rice Within a Multi-species Co-existence System

The prey-seeking behavior of three spiders (X1-Pirata subpiraticus, X2-Clubiona japonicola and X3-Tetragnatha japonica) for brown plant hopper (X4-Nilaparvata lugens) and rice spittle bug (X5-Cal-litettix versicolor) was investigated, as well as how interference between and within species occurred, by using a quadratic regression rotational composite design. Six predation models derived from the analysis of interactions among and within predators and preys were developed. The total predatory capacity of spiders on rice insect pests after coexistence for one day can be expressed as follows: Y3 = 32.795 + 2.25X1 + 1.083X2 + 0.5X3 + 10.167X4 + 3.167X5 - 1.67X12 - 2.42X22 - 3.295X32 - 0.045X42 + 0.455X52 - 3.125X1X2 + 0.375X1X3 -0.625X1X4 - 0.375X1X5 + 0.375X2X3 - 0.875X2X4 + 0.125X2X5 + 0.375X3X4 - 0.375X3X5 + 0.125X4X5. The principal efficiency analysis using this model indicated that increases in insect pest density significantly increased predation by predators; this was much greater than the effect of any single predator. X4 had a greater effect than X5; however, X4 and X5 demonstrated little interspecific interference and even promoted each other and increased predation rates as the densities of the two pests increased. Among the three predators, an increase in the density of X, had the greatest effect on the increase in predation, X3 had the second, X2 the third greatest effect. As predator density increased inter- and intra-species interference occurred, which were largely related to the size, activity, niche breadth, niche overlap and searching efficiency of the predators. X2 produced the greatest interference between different individuals and between any other predator species. X3 had the second greatest, which reduced predation levels at high predator densities. Because of these factors, the highest predation rate was obtained at a prey density of 120 per 4 rice-hills. The optimal proportion of the three predators in the multi-predator prey system was X1: X2: X3 = 5.6:1.3:4.1.

Diversity and Distribution of Spiders in Southwestern Nigeria

The study of diversity and distribution of spiders was carried out at Obafemi Awolowo University, Southwestern Nigeria, in wet and dry seasons between October 2012 and April 2014. Spiders were collected from five different sampling sites in the study area: cultivated land, open field, hill area, house dwelling and aquatic habitat. We found 1824 individuals belonging to 19 different spider families in the study area. 9 families of spiders were present in the hill habitat;12 families of spiders were present in the open field habitat;6 families of spiders were present in house habitat;9 families of spider were present in aquatic habitat. All the 19 families of spiders were present in cultivated habitat. Therefore, cultivated habitat hosted the largest number of spider families in the area of study while house dwellers hosted the least number of spider families. Spiders are evenly distributed among the five habitats in this study and the fifth habitat, teaching and research farm representing cultivated area has the highest distribution of spider species. All the species recorded in Southwestern Nigeria were found in this habitat. In conclusion, 19 different spider families are recorded in Obafemi Awolowo University, Nigeria, during this study. These have enriched the collection of spider in Natural History Museum, Obafemi Awolowo University, Southwestern Nigeria.