Comparative characterization of microRNA-71 of Echinococcus granulosus exosomes

Cystic echinococcosis (CE) is a global zoonotic disease caused by Echinococcus granulosus, posing a great threat to human and animal health. MiRNAs are small regulatory noncoding RNA involved in the pathogenesis of parasitic diseases, possibly via exosomes. Egr-miR-71 has been identified as one of the miRNAs in the blood of CE patients, but its secretory characteristics and functions remains unclear. Herein, we studied the secretory and biological activity of exosomal egr-miR-71 and its immunoregulatory functions in sheep peripheral blood mononuclear cells (PBMCs). Our results showed that egr-miR-71 was enriched in the exosome secreted by protoscoleces with biological activity. These egr-miR-71-containing exosomes were easily internalized and then induced the dysregulation of cytokines (IL-10 and TNF-α), nitric oxide (NO) and key components (CD14 and IRF5) in the LPS/TLR4 pathway in the coincubated sheep PBMCs. Similarly, egr-miR-71 overexpression also altered the immune functions but exhibited obvious differences in regulation of the cytokines and key components, preferably inhibiting proinflammatory cytokines (IL-1α, IL-1β and TNF-α). These results demonstrate that exosomal egr-miR-71 is bioactive and capacity of immunomodulation of PBMCs, potentially being involved in immune responses during E. granulosus infection.

In silico designing of multiepitope-based-peptide (MBP) vaccine against MAPK protein express for Alzheimer's disease in Zebrafish

Understanding the role of the mitogen-activated protein kinases (MAPKs) signalling pathway is essential in advancing treatments for neurodegenerative disorders like Alzheimer's. In this study, we investigate in-silico techniques involving computer-based methods to extract the MAPK1 sequence. Our applied methods enable us to analyze the protein's structure, evaluate its properties, establish its evolutionary relationships, and assess its prevalence in populations. We also predict epitopes, assess their ability to trigger immune responses, and check for allergenicity using advanced computational tools to understand their immunological properties comprehensively. We apply virtual screening, docking, and structure modelling to identify promising drug candidates, analyze their interactions, and enhance drug design processes. We identified a total of 30 cell-targeting molecules against the MAPK1 protein, where we selected top 10 CTL epitopes (PAGGGPNPG, GGGPNPGSG, SAPAGGGPN, AVSAPAGGG, AGGGPNPGS, ATAAVSAPA, TAAVSAPAG, ENIIGINDI, INDIIRTPT, and NDIIRTPTI) for further evaluation to determine their potential efficacy, safety, and suitability for vaccine design based on strong binding potential. The potential to cover a large portion of the world's population with these vaccines is substantial-88.5 % for one type and 99.99 % for another. In exploring the molecular docking analyses, we examined a library of compounds from the ZINC database. Among them, we identified twelve compounds with the lowest binding energy. Critical residues in the MAPK1 protein, such as VAL48, LYS63, CYS175, ASP176, LYS160, ALA61, LEU165, TYR45, SER162, ARG33, PRO365, PHE363, ILE40, ASN163, and GLU42, are pivotal for interactions with these compounds. Our result suggests that these compounds could influence the protein's behaviour. Moreover, our docking analyses revealed that the predicted peptides have a strong affinity for the MAPK1 protein. These peptides form stable complexes, indicating their potential as potent inhibitors. This study contributes to the identification of new drug compounds and the screening of their desired properties. These compounds could potentially help reduce the excessive activity of MAPK1, which is linked to Alzheimer's disease.

Analysis of sheep peripheral blood mononuclear cells in response to Echinococcus granulosus microRNA-71 overexpression

Cyst echinococcosis, caused by Echinococcus granulosus, remains a zoonotic disease posing a great threat to public health and meat production industry. Sheep infected with E. granulosus show relatively high abundance of egr-miR-71 in the sera, but its role is unknown. Using bioinformatics and cell migration and Transwell assays, we comparatively analyzed the proteomes and cell invasion of sheep PBMCs in response to egr-miR-71 overexpression. The results showed that the egr-miR-71 induced a total of 157 proteins being differentially expressed and mainly involved in immune responses. In sheep PBMCs, egr-miRNA-71 overexpression induced significant downregulation of macrophage migration inhibitory factor (MIF) and accordingly promoted cell migration and invasion compared with the control. The results will provide a clue for further investigation of a role of circulating egr-miR-71 in immune responses during E. granulosus infection.

Therapeutic potential of stem cell and melatonin on the reduction of CCl4-induced liver fibrosis in experimental mice model

Liver fibrosis is initial stage of any chronic liver disease and its end stage is develops into cirrhosis. Chronic liver diseases are a crucial global health issue and the cause of approximately 2 million deaths per year worldwide. Cirrhosis is currently the 11th most common cause of death globally. Mesenchymal stem cell (MSCs) treatment is the best way to treat acute and chronic liver disease. The aim of this study is to improve the therapeutic potential of MSCs combined with melatonin (MLT) to overcome CCl4-induced liver fibrosis and also investigate the individual impact of melatonin and MSCs against CCl4-induced liver impairment in animal model. Female BALB/c mice were used as CCL4-induced liver fibrotic animal model. Five groups of animal model were made; negative control, Positive control, CCl4+MSCs treated group, CCl4+MLT treated group and CCl4+MSCs+MLT treated group. Cultured MSCs from mice bone marrow were transplanted to CCl4-induced liver injured mice model, individually as well as together with melatonin. Two weeks after MSCs and MLT administration, all groups of mice were sacrificed for examination. Morphological and Histopathological results showed that combined therapy of MSCs+MLT showed substantial beneficial impact on CCl4-induced liver injured model, compared with MSCs and MLT individually. Biochemically, considerable reduction was observed in serum bilirubin and ALT levels of MLT+MSC treated mice, compared to other groups. PCR results shown down-regulation of Bax and up-regulation of Bcl-xl and Albumin, confirm a significant therapeutic effect of MSCs+MLT on CCI4-induced liver fibrosis. From the results, it is concluded that combined therapy of MSCs and MLT show strong therapeutic effect on CCL4-induced liver fibrosis, compared with MSCs and MLT individually.

Thin Split Thickness Skin Grafting on Human Acellular Dermal Matrix Scaffold for the Treatment of Deep Burn Wounds

BACKGROUND

Use of AlloDerm™ is highly suggested for the treatment of deep burns and burn sequela reconstruction. Scar formation and contracture are recognized as long-term consequences of split-thickness skin autografting, which is applied for full-thickness burn injuries. Mature fibroblasts, in the absence of dermis, seem to secrete collagen in the reformed scar pattern.

OBJECTIVE

To process AlloDerm™ from fresh allograft and use it as a dermal substitute for covering deep wounds in burn patients and evaluate its effectiveness.

METHODS

In this case-series, 7 patients with deep burn wounds involving different locations on the body surface were exposed to combined AlloDerm™ (processed from fresh human allograft) with thin split thickness skin autograft on it. On the 5^th post-operative day, wound dressings were changed to evaluate the graft survival with the human acellular dermal matrix scaffold. To determine the skin profiles, follow-ups continued for at least 6 months.

RESULTS

The results showed excellent graft take, good elasticity, acceptable thickness, and little contracture and scarring according to fix surgeon assessment in 6 patients. Graft rejection happened only in one patient with chronic electrical injury.

CONCLUSION

AlloDerm™ derived from cadaver skin and combination of it with thin split thickness skin auto grafting constitute a cost-effective and favorable option for the treatment of deep burn wounds in our center, considering the increased tendency of the population towards organ donation in the event of brain death.

Comparative analysis of different extracellular vesicles secreted by Echinococcus granulosus protoscoleces

Extracellular vesicles (EVs) are heterogeneous populations of different membrane-wrapped vesicles in size and encapsulated cargo and have recently emerged as a crucial carrier with the functions in intercellular communication, being involved in host-parasite interactions. However, Echinococcus granulosus EVs are not fully described. To separate EVs with a different size, the culture supernatant of E. granulosus protoscoleces (PSCs) was sequentially centrifuged at 2,000g, 10,000g and 110,000g, and the resulting precipitates were accordingly named as 2K, 10K and 110K EVs, respectively. The size and morphology of three different EVs were identified using ZETASIZER NANO and transmission electron microscopy (TEM), respectively. Then mass spectrometry was applied to define protein cargo of EVs and EV internalization was assessed using fluorescent microscopy and flow cytometry. The results showed that 2K EVs mainly ranged from 450 to 950 nm in diameter, 10K EVs ranged from 220 to 390 nm and 110K EVs from 60 to 150 nm. A total of 901 EV proteins were identified, 328 of which were commonly found in the three types of EVs. GO analysis revealed that these proteins were mainly involved in binding (44%) and catalytic activity (44%). Three types of EVs were different in biomarkers (Enolase and 14-3-3) and in reactivity with anti-echinococcosis positive serum. Moreover, 110K EVs were more easily internalized by hepatic cells than 10K EVs as well as 2K EVs (p < 0.0001). These results reveal the physical and biological discrepancy among 2K, 10K and 110K EVs, suggesting a distinct role in host-parasite interactions.

Determination of antimicrobial effect of protamine by transmission electron microscopy and SDS PAGE on Pseudomonas aeruginosa isolates from diabetic foot infection

Objective(s):

Diabetic foot infection is one of the major complications of diabetes leading to lower limb amputations. Isolation and identification of bacteria causing diabetic foot infection, determination of antibiotic resistance, antimicrobial potential of protamine by electron microscopy and SDS-PAGE analysis, arethe aims of this study.

Materials and Methods:

285 pus samples from diabetic foot infection patients were collected from different hospitals of Karachi and Capital Health Hospital, Halifax, Canada. Clinical history of each patient was recorded. Bacterial isolates were cultured on appropriate media; identification was done by morphology, cultural and biochemical tests. Effect of protamine against multi drug resistant strains of Pseudomona aeruginosa was checked by minimum inhibitory concentration in 96 well micro-titer plates. The isolates were grown in bactericidal concentration of protamine on plates to isolate mutants. Effect of protamine on protein expression was checked by SDS- PAGE and ultra-structural morphological changes by transmission electron microscopy.

Results:

Results indicated prevalence of foot infection as 92% in diabetic patients. Major bacterial isolates were Staphylococcus aureus 65 (23%), P. aeruginosa 80 (28.1%), Klebsiella spp. 37 (13%), Proteus mirabilis 79 (27.7%), and Escherichia coli 24 (12%). These isolates were highly resistant to different antibiotics. MIC value of protamine was 500 µg/ml against P. aeruginosa. SDS-PAGE analysis revealed that protamine can suppress expression of various virulence proteins and electron micrographs indicated condensation of cytoplasm and accumulation of protamine in cytoplasm without damaging the cell membrane.

Conclusion:

P. aeruginosa and S. aureus were the major isolates expressing multi-drug resistance and protamine sulfate represented good antimicrobial potential.

miRNA-seq of Echinococcus multilocularis Extracellular Vesicles and Immunomodulatory Effects of miR-4989

Alveolar echinococcosis caused by Echinococcus multilocularis is an important zoonotic disease. In the infected mice, emu-miR-4989-3p is present in sera, but its role remains unknown. Using high-throughput sequencing and qPCR, emu-miR-4989-3p was herein confirmed to be encapsulated into E. multilocularis extracellular vesicles. In the transfected macrophages, emu-miR-4989-3p was demonstrated to significantly inhibit NO production compared to the control (p < 0.05). Moreover, transfection of emu-miR-4989-3p also gave rise to the increased expression of TNF-α (p < 0.01). Furthermore, emu-miR-4989-3p induced the dysregulation of several key components in the LPS/TLR4 signaling pathway compared with the control, especially TLR4 and NF-κB that both were upregulated. Conversely, the NO production and the expression of TNF-α, TLR4 and NF-κB tended to be increased and decreased in the mimics-transfected cells upon emu-miR-4989-3p low expression, respectively. These results suggest that emu-miR-4989-3p is one of ‘virulence’ factors encapsulated into the extracellular vesicles, potentially playing a role in the pathogenesis of E. multilocularis.

Effect of glycine: Studying memory and behavioral changes in mice

Glycine is an important chemical mediator of nervous system that plays a vital role in memory and other neurological functions. Therefore, the effect of glycine on these traits must be studied to understand biological mechanisms of intricate neurological system. We investigated the effect of different doses of glycine on memory and behavior using 30 albino mice models (treated and control). After two weeks of glycine dosing, we performed light and dark activity and novel-object recognition (NOR) tests to assess the cognitive traits. Brain and blood samples were taken and kept at -70°C using ultra-low temperature freezer. Neurochemical estimation of blood glycine level was estimated by high-performance liquid chromatography with electrochemical detectors (HPLC-ECD). Concentration of glycine (100, 300 and 500 mg/kg) is significantly observed (p<0.01) and it changes due to physiological variations in N-methyl-Daspartate (NMDA) an important neurotransmitter for memory. We observed significant increase in serotonin metabolites including 5-hydroxy tryptophan (5-HT, p<0.05) and 5-hydroxy indole acetic acid (5-HIAA, p<0.001) levels. Similarly,effects were found in case of dopamine (DA, p<0.05) and its metabolites: 3, 4-Dihydroxyphenylacetic acid (DOPAC,p<0.001) and homovanillic acid (HVA, p<0.001). Histopathological investigation of brain tissues showed cellular clumps at cortical junctions at higher doses of glycine as compared to control. These findings revealed that dose dependent concentration of glycine can be useful for memory loss and behavior deficits.

Identification of emu-TegP11, an EF-hand domain-containing tegumental protein of Echinococcus multilocularis

Tegumental proteins (TegPs) are a group of proteins that coat on the surface of worms, mainly being involved in ion uptake and immune evasion. Echinococcus species have many TegPs, but none of them have been characterized and their role remains unclear. The genome-wide analysis revealed that there were at least 14 tegp genes (tegp1 - 14) in Echinococcus species, the majority of which were found to contain an EF-hand domain or a dynein light chain-like domain or both. Despite low identity, all TegP11 proteins from 25 flatworms were conserved in structure. Echinococcus multilocularis TegP11 (emu-TegP11) was verified to be secreted by extracellular vesicles and to be localized in different spatiotemporal patterns in protoscoleces. Moreover, emu-TegP11 was also shown to have weak or no Ca²⁺-binding capacity. In treated macrophages, emu-TegP11 interfered with the small RNA-induced silencing pathway via inducing ectopic expression of some key component genes. Additionally, emu-TegP11 remarkably promoted NO secretion possibly by upregulation of inos gene expression (p < 0.05). It was further shown that emu-TegP11 acted as a suppressor of inflammation, with il-12B and il-1β being significantly down-regulated (p < 0.01), and il-10 and il-4 being significantly upregulated (p < 0.05). The study demonstrates a regulatory role of emu-TegP11, likely acting as a immunomodulator to be involved in regulation of host immune system during Echinococcus infection.

Molecular detection of Ehrlichia canis in dogs from three districts in Punjab (Pakistan)

Canine monocytic ehrlichiosis is a tick-borne disease caused by an intracellular alpha-proteobacterium, Ehrlichia canis, which replicates within mononuclear cells in the host. This study was designed to use a polymerase chain reaction (PCR) protocol for the molecular detection of E. canis by the amplification of a portion of its 16S rRNA gene, as well as the effects of this alpha-proteobacterium on the haematological parameters of the sampled dogs and the risk factors associated with E. canis infection. A total of 151 blood samples were collected from dogs of various breeds at three sampling sites (Lahore, Rawalpindi/Islamabad and Multan) in Punjab, Pakistan. Data regarding the epidemiological factors (including age, gender, breed, body temperature, deworming, vaccination, mucous membrane status, hydration status, the presence of haematuria and tick infestation) were collected through a questionnaire at the time of sample collection. A 400 bp DNA fragment of the 16S rRNA gene of E. canis was amplified from 42 dog blood samples (28% of the total), [Lahore (N = 24), Rawalpindi/Islamabad (N = 13) and Multan (N = 05)] through PCR. Data analysis revealed that the character of the animals (age, sex and breed) had no significant association (P > 0.05) with the presence of E. canis. Various haematological parameters were also compared, and the results revealed that all of the parameters remained unaffected, except significantly lower white blood cell counts (P = 0.004) in E. canis-positive blood samples, as compared with the control group. We concluded that this is the first molecular confirmation of canine infection by E. canis using PCR. Moreover, no specific epidemiological parameter was found associated with the prevalence of E. canis in dogs.

Correlates of myopia in students of Bahauddin Zakariya University, Multan

The present study was conducted to determine the prevalence of myopia in young students of Bahaudin Zakariya University, Multan. A total sample of 620 students of both gender (male=295; female=325) was collected during 2014. The data was divided in two breeding pattern groups, five groups on account of age at myopia onset and different family size. Out of 620 subjects, 150 had myopia (male=85; female=65). The overall prevalence of myopia was 24.19%. The myopia prevalence was apparently higher in males 28.8% as compared to females 20%. It was observed that myopia was more in age group 21 (37.33%) and less in age group 18 (2.67%). Myopia was found to be higher in inbreeding group (cousin marriage) 56.67% when compared with out-breeding group 43.33% and was found significantly (P< 0.05) more 69.33% in family size of 6-9 as compared 5 (5.33%) respectively.

Suppression of nemo-like kinase by miR-71 in Echinococcus multilocularis

Echinococcus multilocularis metacestodes are a causative pathogen for alveolar echinococcosis in human beings, and have been found to express miRNAs including emu-miR-71. miR-71 is evolutionarily conserved and highly expressed across platyhelminths, but little is known about its role. Here it was shown that emu-miR-71 was differentially expressed in protoscoleces and was unlikely to be expressed in neoblasts. The results of the luciferase assay indicated that emu-miR-71 was able to bind in vitro to the 3'-UTR of emu-nlk, encoding a key regulator of cell division, causing significant downregulation of luciferase activity (p < 0.01) compared to the negative control and the construct with mutations in the binding site. Consistent with the decreased luciferase activity, transfection of emu-miR-71 mimics into protoscoleces notably repressed emu-NLK (p < 0.05). These results demonstrate the suppression of emu-nlk by emu-miR-71, potentially involved in the protoscolex development.

miRNA profiling in the mice in response to Echinococcus multilocularis infection

miRNAs are small non-coding regulatory RNAs and actively contribute to the pathogenesis of parasitic diseases in multiple ways. The influence of Echinococcus multilocularis infection on host miRNAs remains unclear. Herein, it was shown that E. multilocularis infection disturbed the expression of 4 of 10 genes essential to miRNA biogenesis in the mouse liver, including ago1, ago4, tarbp2 and xrn2. Comparative analysis of deep sequencing data identified 46 differentially expressed miRNAs with 93.5% (43/46) being down-regulated, some of which are associated with modulation of liver cell death and fibrosis, and GO analysis revealed that these miRNAs were mainly enriched in signal transduction (p<0.008). Moreover, 57 miRNAs were commonly found to be edited in complex patterns in both control and E. multilocularis-infected samples. In some miRNAs, editing of nucleotides at the same or/and distinct positions in a given miRNA occurred in different frequencies. Correlation analysis showed that the mutation and editing rates of 57 commonly edited miRNAs were significantly correlated between both samples (r=0.9974, p<0.0001), suggesting little effect of E. multilocularis infection on miRNA mutation and editing. These results provide a rich and informative data for further studies of a role of host miRNAs during E. multilocularis infection.

Regulatory effects of Echinococcus multilocularis extracellular vesicles on RAW264.7 macrophages

Extracellular vesicles (EVs) play a role in intercellular communications via exchanging biological molecules, being involved in host-parasite interplay. Little is to date known about E. multilocularis EVs and their biological activities. Here spherical EVs secreted by E. multilocularis metacestodes were shown to range predominately from 34nm to 95nm in diameter. A total of 433 proteins were identified in the EVs, and the proteins involved in binding (42%) and catalytic activity (41%) were most frequently represented. Moreover, the proteins associated with EV biogenesis and trafficking, including annexin, 14-3-3, tetraspanin and heat shock protein 70kDa, were highly enriched. It was shown that the EVs remarkably suppressed NO produced by activated RAW macrophages via downregulation of inducible nitric oxide synthase expression (p <0.01). Suppression of pro-inflammatory cytokines, especially IL-1α and IL-1β, was also observed post treatment with the EVs. Conversely, increased expression of the majority (10/11) of key components involved in the LPS/TLR4 pathway was induced by the EVs. These results demonstrate a regulatory effect of E. multilocularis EVs on macrophages, suggesting a role in parasite-host interactions.

Paediatric burn injuries requiring hospitalization in Fars, Southern Iran

The aim of this study was to determine the demographic characteristics of burnt children in need of hospitalization, causes of burns and associated complications in Fars province, Iran. This is a retrospective cross-sectional study. Files of all children under 15 years of age who were hospitalized in the only burn referral centre of Fars province were evaluated. Data regarding age, gender, location (urban, rural), burn surface area (BSA), cause of burn, length of hospital stay and complications were extracted from patients' files. Data were analyzed using SPSS, version 22 and the Chi-square test. A p-value of less than 0.05 was considered as statistically significant. A total of 122 patients (54.9% males) were studied. Children from rural areas were hospitalized 1.4 times more often than urban children. Overall, 31.2% of admissions occurred in winter. Burning with hot liquids (scalding) was the most common cause of burns (56.6%, n = 69). Mean BSA was 12.29 ± 21.18% and mean length of hospital stay was 7.59 ± 12.78 days. Burn complications were seen in 19 cases (15.6%). One child died due to inhalational thermal injury. This study showed that burns mostly occur in boys, in the winter and in rural areas of Fars province. Furthermore, scald burns are the most common type of burn injury. Since a significant number of children suffer from permanent complications following burn injuries, special planning is needed to prevent this type of injury.

Protective effect of distillated Nerium oleander on heart of type 2 diabetic rats

OBJECTIVES

The current study aims to investigate the possible role of NO distillate either for therapeutic or for protective potential in diabetic cardiomyopathy.

BACKGROUND

Protective and restorative effects of distillated Nerium oleander (NO) on the diabetes-induced electrophysiological and structural alterations were investigated.

METHODS

Type 2 diabetes was induced by combination of single dose streptozotocin injection and high fat diet for four weeks. Experimental groups were designed as follows: control, diabetic, restorative-NO treated diabetic and protective-NO treated diabetic. Intracellular action potentials (AP) and contractile activities were measured form left ventricular papillary muscle strips as well as histopathological examination of heart tissue and biochemical examinations of serum were performed.

RESULTS

Type 2 diabetes induced AP prolongation was prevented with both ways of NO treatments. Moreover, treatments produced nearly complete restorations of diabetes-induced depressed amplitude and altered kinetics of contractile activities. In parallel to electrophysiological parameters, both histopathological and biochemical results indicates the NO induced beneficial effects on the diabetes related alterations.

CONCLUSION

Distillated Nerium oleander (NO) can be a highly potential therapeutic or preventive agent on the diabetes induced excitation-contraction coupling alterations (Tab. 3, Fig. 3, Ref. 23).

The effects of estradiol on cardiac muscle electrophysiology in orchiectomized rat model: a new insight to side effects caused by castration

OBJCTIVE

Although the testosterone has a protective effect on heart, patients having maximal androgen blockade due to prostate cancer resembles endothelial dysfunction and cardiac problems when compared to normal population. We aimed to test the effect of 17 beta estradiol on the orchiectomized male rat heart electrophysiology and ion channel expression levels.

MATERIALS AND METHODS

This study was conducted on 27 male rats with 4 groups (healthy, orchiectomized, orchiectomized+17 beta estradiol treated and orchiectomized+vehicle treated). Action potentials and contractions were recorded simultaneously, while expressions of the calcium and potassium ion channels were measured.

RESULTS

Testosterone depletion for 4 weeks has caused a significant prolongation in the action potential durations and decrease in maximal contraction force as well as a deceleration. While this depletion suppressed expression of potassium channels, it increased the expression of calcium ion channels. Application of estradiol on the other hand, except for the calcium ion channel expression, had no positive effect on the tested parameters.

CONCLUSIONS

Testosterone has a markedly important and protective effect on male cardiac muscle preparations while estrogen does not have any. It is predicted that testosterone has showed this effect by means of modulation of some key points of excitation-contraction pairing of cardiac muscle.

Neospora caninum prevalence in dogs raised under different living conditions

Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dogs are important in the epidemiology of N. caninum because they act as definitive hosts shedding oocysts in the environment. Vertical transmission of the parasite is well recognized as an important aspect of the epidemiology of the parasite but the importance of horizontal transmission has been less studied. A N. caninum competitive ELISA was used to examine serum samples from 600 dogs that were raised under 4 different living conditions. Samples from 138 dogs living on 24 dairies with a prevalence (0-70%) of anti-N. caninum antibodies in the cattle, 294 pet dogs without neurological signs, 76 from pet dogs exhibiting neurological signs, and 92 stray dogs were examined. The overall seroprevalence of N. caninum was 23.5% (95% CI = ± 2.99) in the 600 dogs. Significant (P < 0.05) differences were observed between the 4 different populations of dogs. The number of N. caninum positive samples were: 51 (36.9%, 95% CI = ± 3.09) of 138 dogs from dairies, 31 (10.5%, 95% CI = ± 6.38) of 294 pet dogs without neurological signs, disorders, 22 (28.9%, 95% CI = ± 6.70) of 76 pet dogs with neurological signs, and 37 (40.2%, 95% CI = ± 2.83) of 92 stray dogs. Seropositivity to N. caninum in dogs from dairies was associated with a high prevalence of N. caninum antibodies in the cattle. At the 3 dairies where no dogs were present, the seroprevalence to N. caninum in the cattle was significantly lower (P < 0.05) than in the 21 dairies where dogs were present. Seroprevalence was significantly higher (P < 0.05) in male dogs (97 of 366; 26.5%, 95% CI = ± 3.40) than in female dogs (44 of 234; 18.8%, 95% CI = ± 5.65). Seroprevalence in dogs increased with age suggesting postnatal exposure to N. caninum infection however, this increase was not significant (P > 0.05). The prevalence of N. caninum antibodies was not significantly (P>0.05) different in dogs based on breed. These findings suggest a relationship between N. caninum infection of dogs from dairies and cattle on these dairies. However, further research is required to determine what is the most important way dogs acquire infection and how to prevent dogs from shedding oocysts.

Human split-thickness skin allograft: skin substitute in the treatment of burn

BACKGROUND

Human skin allograft has been used as wound coverage for a long time; it is one of the most successful and widely used dressings for burn wounds in the world.

OBJECTIVE

To prepare a freeze-dried human split-thickness skin allograft and evaluate its cytotoxicity, the structure and physical properties after processing methods and clinical efficacy in burn patients.

METHODS

After ensuring tissue safety, we lyophilized human cadaveric partial thickness skin and exposed it to gamma radiation. Histopathological and immunohistochemical properties, tensile strength and in vitro cytotoxicity were assayed for the skin samples. Then, we tested the samples in 11 patients with deep skin burn.

RESULTS

On histological and histopathological examinations, we found a normal skin structure. The tensile strength of the rehydrated freeze-dried human skin allograft was not lesser than the fresh human skin. Cell viability in MTT testing was more than 95%. None of our patients showed any signs of immunological reactions or complications.

CONCLUSION

Gamma-irradiated freeze-dried human split-thickness skin is safe and non-toxic and can be used for the treatment of patients with deep skin burn.

Characterizing the mesencephalon using susceptibility-weighted imaging

BACKGROUND AND PURPOSE

The mesencephalon is involved in a number of human neurodegenerative disorders and has been typically imaged with T1-, T2- and T2*-weighted methods. Our aim was to collect high-contrast susceptibility-weighted imaging (SWI) data to differentiate among and within the basic mesencephalic structures: namely, the red nucleus, substantia nigra, and crus cerebri.

MATERIALS AND METHODS

High-resolution SWI, 3D T1-weighted, and T2-weighted data were collected to study contrast in the mesencephalon at 1.5T and 4T. Contrast between structures was calculated for SWI high-pass (HP)-filtered-phase, T1 gradient-echo, and spin-echo T2-weighted data.

RESULTS

SWI HP-filtered-phase data revealed similar contrast for the red nucleus and substantia nigra when compared with T2-weighted imaging. However, SWI was able to show structures within the red nucleus, substantia nigra, and medial geniculate body that were invisible on T2-weighted imaging. T1-weighted imaging, on the other hand, did not reveal measurable contrast for any of the structures of interest. SWI HP-filtered-phase data at 4T agreed well with india ink-stained cadaver brain studies, which appear to correlate with capillary density.

CONCLUSIONS

With SWI, it is possible to create better anatomic images of the mesencephalon, with improved contrast compared with conventional T1- or T2-weighted sequences.

Bupivacaine and ropivacaine: comparative effects on nerve conduction block

Unlike other drugs which act in the region of the synapse, local anesthetics are agents that reversibly block the generation and conduction of nerve impulses along a nerve fiber. This study aims to investigate the comparative inhibitions of bupivacaine and ropivacaine on the frog sciatic nerve. Isolated nerves were transferred to the nerve chamber which includes Ringer's solution. The nerves were stimulated by standard square wave pulse protocols and the responses were recorded with conventional systems. Bupivacaine (n = 8) and ropivacaine (n = 8) were administered in the nerve chamber bath with cumulative concentrations (10(-9) to 10(-3) M) and the effects were monitored for variable time periods (5, 10 and 15 min). Both bupivacaine and ropivacaine significantly depressed the compound action potential (CAP) parameters in a dose-dependent (p < 0.05) and reversible manner. Difference in the effects of these two drugs was detectable only when the dose (> or =10(-5) M) and exposure time (15 min) were increased. Percent inhibitions in maximum derivatives and latency-period measurements have shown that ropivacaine is not only fast but also much more powerful in conduction block for longer and higher doses. Bupivacaine, on the other hand, is effective in the group of fibers with relatively slower conduction velocity for all the measured doses and time periods. In conclusion, ropivacaine has a sensory specific side of action, when compared with the bupivacaine.

Avian influenza in Pakistan: outbreaks of low- and high-pathogenicity avian influenza in Pakistan during 2003-2006

From November 2003 to June 2004 an epidemic of high pathogenicity avian influenza (HPAI) virus of subtype H7N3 affected the major layer and broiler-breeder raising areas of the country. This was accompanied by an outbreak of low pathogenicity avian influenza (LPAI) virus of type H9N2 in broilers and layers, which continued during 2005. Subsequently, in February 2006 avian influenza virus (AIV) subtype H5N1 was for the first time found in two isolated commercial flocks in this country. The HPAI outbreak of 2003-2004 was eventually overcome by enforcing biosecurity measures, controlling poultry movements, using inactivated vaccines, and introducing a comprehensive AI surveillance network throughout the country. However, similar measures undertaken to control H9N2 outbreaks have not been successful in the affected areas, with continuing increased mortality and heavy production losses in broilers and layers, respectively. A similar strategy has been devised to combat the spread of newly introduced H5N1 HPAIV. The description of these outbreaks and the results of the control strategy are reported here.

Vegetable oils used as vitamin E vehicle affect the electrical activity of the rat heart

The aim of this study is to define the possible effects of vegetable oils used as vitamin E vehicle on the electrical activity of the rat heart. To test the possible effects of vitamin E vehicles we studied the effect of i.p. injected corn oil, hazelnut oil or peanut oil on the action potential parameters recorded in both papillary and left atrial muscle strips. Four experimental groups were used. The control group was injected (i.p.) with distilled water, while the three remaining groups received injections of corn oil, hazelnut oil, or peanut oil for five weeks (in a dose of 0.4 ml/kg/day--minimum amount of oil in which vitamin E could be dissolved). We used borosilicated (15-20 megaohms) capillary electrodes and intracellular action potentials (AP) were recorded in isolated papillary and left atrium muscle strips. While administration of three different types of vegetable oil had no significant effect on AP parameters of papillary muscle, they significantly prolonged the repolarization phase of AP in atrial strips. These results show that vegetable oils used as vitamin E vehicles may alter the electrical activity of the heart in a tissue-dependent manner. The present data indicate that the possible effect of vegetable oil vehicles should be kept in mind while evaluating the possible effects of in vivo vitamin E administration.

Plasma and erythrocytes antioxidant status and trace element levels in proteinuric patients with moderate glomerular function

The objective of the study was to investigate the effect of moderate glomerular dysfunction on oxidative stress. We determined the plasma and erythrocyte malondialdehyde (MDA) levels, as a marker of lipid peroxidation, erythrocyte glutathione (GSH) levels and activities of GSH-Px, GSH Red and SOD as an antioxidant enzymes, and plasma trace element levels containing Fe, Cu and Zn in twenty proteinuric patients (6.8 +/- 5.1 g/day) with moderate glomerular function and in 20 anemic control subjects. We found that the erythrocyte and plasma MDA levels and erythrocyte GSH-Px activities were significantly higher (p < 0.001, p < 0.001, p < 0.001, respectively) and the erythrocyte GSH levels and activities of GSH-Red and SOD activities were significantly lower (p < 0.001, p < 0.001, p < 0.001, respectively) in the patients than in the anemic subjects. Plasma Fe and Zn levels were not to be found significantly different in the patients compared to the anemic subjects. But plasma Cu levels were significantly higher in the patients (p < 0.05) when compared with the levels of anemic subjects. This study was concluded that cellular antioxidant activity decreases in proteinuric patients with moderate glomerular function. This may increase lipid peroxidation reactions by causing oxidative stress in erythrocyte membranes.

Prospective validation of single plasma sample 99mTc-ethylenedicysteine clearance in adults

99mTc-L,L-ethylene, L, dicysteine (EC) clearance shows strong correlation with orthoiodohippurate clearance, and it is possible to estimate effective renal plasma flow from 99mTc-EC clearance. In routine clinical studies, it is practical to use the one or two plasma sample method instead of multiple plasma samples for clearance determination. A single-sample technique was developed for 99mTc-EC, and a regression formula was generated. A prospective study tested the validity of this regression formula.

METHODS

The study population was composed of 26 patients with a wide range of renal function. Multiple plasma sample 99mTc-EC clearances were calculated from all patients using the open two-compartment model. Single plasma sample clearances were also determined from the 54-min plasma sample using the regression formula published previously.

RESULTS

The multiple-sample plasma clearance of 99mTc-EC ranged from 46 to 668 mL/min with a mean of 300.76 +/- 150.73 mL/min. The clearances obtained from the 54-min plasma sample ranged from 49 to 699 mL/min, with a mean of 297.39 +/- 152.23 mL/min. There was an excellent correlation between the clearances obtained by the two techniques (r = 0.99, slope = 0.9911). The standard error of estimation was found to be 25.9 mL/min.

CONCLUSION

This study suggests that 99mTc-EC clearance can be estimated from 54-min plasma samples with an acceptable error of estimation for most routine clinical studies.

The role of oxygen free radicals in acute renal failure complicating obstructive jaundice: an experimental study

Oxidant injury is considered to be an important mechanism in the pathophysiology of acute renal failure. It has been thought that decrease in extracellular and intracellular fluid and endotoxemia seen in obstructive jaundice may cause an increase in production of oxygen free radicals and impairment in antioxidant defense mechanism. This study is designed to investigate the possible role of oxidant injury in renal failure seen in jaundiced patients. In this study, 28 rats were divided into four groups: Control (C)(N = 7); Renal ischemia (RI)(N = 7); Obstructive jaundice+renal ischemia (OJ+RI)(N = 7); Obstructive jaundice (OJ)(N = 7). All groups were compared with each other according to renal failure findings and enzyme activities, such as Xanthine oxidase (XOD), Superoxide Dismutase (SOD) and Catalase in renal cortex and Glutathione Peroxidase (GSH-Px), in blood at 3rd day after ischemia and reperfusion. Renal failure findings monitored by blood urea and creatinine levels, seemed more evident in OJ+RI than RI group (p < 0.05). When compared with RI, in OJ+RI group, increase in XOD activity at 3rd day was statistically significant [0.259 +/- 0.01 U/g (tissue) and 0.362 +/- 0.03 U/g (tissue) respectively] (p < 0.05). SOD and GSH-Px activities of each ischemic group at 3rd day were decreased compared to non-ischemic groups. This fall was significant (p < 0.05). But there was no statistical difference between jaundiced and non-jaundiced groups. Alterations in catalase activities also had no statistical significance. These findings may suggest that the injury induced by oxygen free radicals at re-oxygenation of tissue after ischemia may also play a role in the pathogenesis of acute renal failure developed in obstructive jaundice.

Functional evaluation of renal transplants with scintigraphy

A variety of techniques have been employed to assess renal function and its evolution after transplant surgery. Since initial perfusion studies are easy to perform, one may be tempted to rely on 99mTc-diethylenetriaminepentaacetic acid (DTPA) scanning alone. Some discrepancies have been observed between perfusion studies and clinical outcome of the renal transplant patients however. We therefore decided to evaluate both 99mTc-DTPA and 131I-hippuran renal scanning in 28 renal transplant patients. Sixty 99mTc-DTPA perfusion and 131I hippuran scintigraphies were performed using a same-day protocol. The examinations were repeated in 14 patients at weekly or monthly intervals to monitor the clinical trend of these patients. The results of this study indicate that, for early detection of the kidney problems, 131I-hippuran scintigraphy was superior to 99mTc-DTPA perfusion scans, but for the proper clinical management of renal transplant patients, both procedures should be utilized.

Microbiological Quality of Tehineh Manufactured in Saudi Arabia

Tehineh is a product obtained by the milling of dehulled and roasted white sesame seeds. A total of 50 tehineh samples was collected from ten processing plants in Saudi Arabia. These samples were examined by standard procedures for aerobic plate counts (APC) and counts of coliforms, Staphylococcus aureus , Bacillus cereus , Clostridium perfringens , molds and yeasts and detection of salmonellae. APC of tehineh ranged from 20 to 170,000 CFU/g. The counts for coliforms, S. aureus , B. cereus , C. perfringens , and molds and yeasts ranged from <10 to 300, <10 to 400, <10 to 250, <10 to 100, <10 to 120 and <10 to 50 CFU/g, respectively. Two out of ten tehineh plants (20%) were positive for four Salmonella serotypes. Four Salmonella serotypes recovered were Salmonella hadar , Salmonella agona , Salmonella einsbuettel and Salmonella ubrecht , with S. hadar being the most predominant. The results of this investigation indicate that foodborne pathogens present in tehineh may constitute a potential public health hazard.

Circulation parameters during intravenous and intra-arterial administration of increasing doses of prostaglandin E1 in healthy subjects

Increasing doses of prostaglandin E1 given intravenously do not influence the hemodynamic parameters up to a dosage of 1500 ng/min. Intra-arterial administration of a mixture of nucleotides and nucleosides in therapeutic doses induces an increase in the blood flow volume at rest of up to 400%. With dosages of 20 ng/min and more, intra-arterial administration of PGE1 induces only a slight increase in the blood flow volume of the extremity under treatment. The therapeutic effects of the substance, therefore, are probably more due to other mechanisms of action than to hemodynamic effects.

Microbiological Quality of Shawarma in Saudi Arabia

A total of 108 shawarma (cooked meat) samples were aseptically collected from various fast-food restaurants in Riyadh, Saudi Arabia. These samples were examined by standard procedures for determination of aerobic plate count (APC), and counts of coliforms, Staphylococcus aureus , Clostridium perfringens , and the detection of salmonellae. The APC ranged from 10² to 3.0 × 10⁸ CFU/g. The counts for coliforms, S. aureus and C. perfringens ranged from <10 to 10⁶, <10 to 10⁵ and <10 to 10⁶ CFU/g, respectively. Twelve percent of the shawarma samples was positive for Salmonella . The results of this investigation indicate that foodborne pathogens present in shawarmas constitute a potential public health hazard.

Inhibition of growth rate of Escherichia coli induced by extremely low-frequency weak magnetic fields

Cultures of Escherichia coli kept at 0 degree C in a phosphate buffer solution were exposed to a sinusoidal weak 60- or 600-Hz magnetic field of strength 2 X 10(-3) Tesla. A decrease of more than 40% in bacterial count was observed after a 60-h exposure to the magnetic field. Electron micrographs of exposed bacteria show ruptured cell walls, possibly due to the breaking away of flagella under the influence of the sinusoidally varying electromotive force.

Antimicrobial Effect of Butylated Hydroxyanisole and Butylated Hydroxytoluene on Staphylococcus aureus 1

The antimicrobial effect of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on three enterotoxigenic strains of Staphylococcus aureus in Brain Heart Infusion broth (BHI) was evaluated by turbidity measurements. Also, the interaction of these compounds with pH and NaCl on growth of S. aureus strain 100 was measured. Inhibition of S. aureus growth increased with an increase in the concentration of BHA and/or BHT. Complete inhibition of S. aureus growth occurred in BHI with 1.12 μmole of BHA/ml or 0.70 μmole of BHT/ml as well as with a combination of 0.25 μmole of both BHT and BHA/ml. Inhibition of S. aureus growth by BHA or BHT was substantial at pH 7.0 and with 2% NaCl. When 0.84 μmole or greater of BHA/ml and 0.47 μmole or greater of BHT/ml were added to BHL, growth of S. aureus 100 was inhibited to the extent that enterotoxin A could not be detected after 24 h of incubation.