Agmatine ameliorates valproic acid-induced depletion of parvalbumin-positive neuron

Autism spectrum disorder (ASD) is a widespread neurodevelopmental disorder with unknown etiology. Dysfunction of several brain areas including the prefrontal cortex (PFC), hippocampus, and cerebellum is involved in cognitive and behavioral deficits associated with ASD. Several studies have reported a reduction in the number of parvalbumin-immunoreactive (PV+) neurons in brain areas of ASD patients and animal models such as a shank mutant mouse model and rodents receiving fetal valproic acid (VPA) administration. Developing therapeutic interventions that restore PV interneurons can be the future therapeutic approach to ASD. The present study examined the possible effect of agmatine (AG), an endogenous NMDA antagonist, on the number of PV+ neurons in a VPA animal model of autism. The therapeutic effects of AG in ameliorating ASD-like behaviors were previously reported in VPA rats. AG was gavaged at dosages of 0.001, 0.01, and 0.1 mg/kg from gestational day (GD) 6.5 to 18.5, and the number of PV interneurons was analyzed by immunohistochemistry in the 1-month-old rats. Prenatal VPA (GD 12.5) or AG led to a decrease of PV neurons in the PFC, Cornu ammonia (CA1), and molecular layers (MLs) of the cerebellum. However, exposure to AG restored the PV population induced by VPA. AG may modify underlying neuronal mechanisms resulting in the increased survival or restoration of the PV population.

Thyroid dysfunction following vaccination with COVID-19 vaccines: a basic review of the preliminary evidence

PURPOSE

The safety and efficacy of the several types of COVID-19 vaccines, including mRNA-based, viral vector-based, and inactivated vaccines, have been approved by WHO. The vaccines can confer protection against severe SARS-CoV-2 infection through induction of the anti-spike protein neutralizing antibodies. However, SARS-CoV-2 vaccines have been associated with very rare complications, such as thyroid disorders. This review was conducted to highlight main features of thyroid abnormalities following COVID-19 vaccination.

METHODS

A comprehensive search within electronic databases was performed to collect reports of thyroid disorders after vaccination with COVID-19 vaccines.

RESULTS

Among 83 reported cases including in this review, the most cases of thyroid abnormalities were observed after vaccination with mRNA-based vaccines (68.7%), followed by viral vector vaccines (15.7%) and 14.5% cases following inactivated vaccines. Subacute thyroiditis (SAT) was the most common COVID-19 vaccination-related thyroid disease, accounting for 60.2% of all cases, followed by Graves' disease (GD) with 25.3%. Moreover, some cases with focal painful thyroiditis (3.6%), silent thyroiditis (3.6%), concurrent GD and SAT (2.4%), thyroid eye disease (1.2%), overt hypothyroidism (1.2%), atypical subacute thyroiditis (1.2%), and painless thyroiditis with TPP (1.2%) were also reported. Overall, in 58.0% of SAT cases and in 61.9% of GD cases, the onset of the symptoms occurred following the first vaccine dose with a median of 10.0 days (ranged: 3-21 days) and 10.0 days (ranged: 1-60 days) after vaccination, respectively. Moreover, 40.0% of SAT patients and 38.1% of GD patients developed the symptoms after the second dose with a median of 10.5 days (ranged: 0.5-37 days) and 14.0 days (ranged: 2-35 days) after vaccination, respectively.

CONCLUSION

Fortunately, almost all cases with COVID-19 vaccination-associated thyroid dysfunctions had a favorable outcome following therapy. The benefits of COVID-19 vaccinations in terms of terminating the pandemic and/or reducing mortality rates can exceed any risk of infrequent complications such as a transient thyroid malfunction.

Prophage Typing of Staphylococcus aureus Strains Isolated from Broiler Poultry

Staphylococcus aureus is a well-known commensal and pathogen agent of many wild and domestic animals. A wide variety of infections can be caused by S. aureus, from suppurative skin infections to life-threatening septicemia. This study was conducted to determine the prophage typing and the pattern of antibiotic resistance of S. aureus isolated from broiler poultry before they have been slaughtered. In this study, 200 nasal and cloacal swab samples from 20 different flocks were collected for bacterial isolation. Staphylococci were identified using biochemical and molecular methods before being examined for mecA gene detections in all samples resistant to oxacillin and cefotaxime. The highest value of antibiotic resistance was observed against ciprofloxacin (94%), and the maximum value of susceptibility was to gentamicin (85%). Twenty-eight (27%) samples were resistant to oxacillin. In methicillin-resistance Staphylococcus aureus (MRSA) isolates, 5 prophage types were observed, where the SGB prophage with a frequency of 75% was identified as a dominant prophage; in isolates of S. aureus susceptible to methicillin, 8 prophage types were observed, where SGFa prophage with a frequency about 82% was the dominant prophage. The high prevalence of MRSA isolates can indicate the risk of transmission of these bacteria to the food cycle. Furthermore, existence of various prophages in these isolates can be considered a threat to public health in producing pathogenicity factors in this bacterium while also empowering other bacterial pathogenicity, even other bacterial genera.

De-oiled soy lecithin positively influenced growth performance, nutrient digestibility, histological intestinal alteration, and antioxidant status in turkeys fed with low energy diets

1. The purpose of this research was to investigate the effects of supplementing an emulsifier (de-oiled soybean lecithin (DSL)) in a low metabolisable energy (ME) diet on growth performance, nutrient digestibility, carcase characteristics, intestinal morphology, blood metabolites, and antioxidant status in growing turkeys.2. A total of 480 one-day-old turkeys were assigned to one of four dietary treatments with of eight replicates of 15 birds each. Experimental treatments included a basal diet (BE) with commercially recommended levels of ME, a reduced energy diet (RE) with 0.42 MJ/kg reduction in dietary ME content, the RE diet + 1 g/kg DSL (DSL-1), and RE + 2 g/kg DSL (DSL-2).3. After 112 days, the body weight, average daily gain, and feed:gain in turkeys fed the supplemented for BE diets were better (P < 0.05) than in those fed RE, and those fed diet DSL-2 had the best performance. Although the RE diet decreased abdominal fat and relative liver weight (P < 0.05), compared to the BE diet, and supplementation with either level of DSL did not influence these variables.4. There were linear increases (P < 0.05) in fat digestibility, nitrogen-corrected apparent ME, and duodenal villus height, villus height/crypt depth ratio, and villus surface area in LE diet supplemented with DSL. From the jejunal morphology, crypt depth was decreased by DSL-supplemented diets (P < 0.05).5. Serum triglyceride, total cholesterol, and malondialdehyde concentrations were lower, whereas the serum superoxide dismutase activity was greater for the DSL-2 group compared to the BE and RE groups (P < 0.05).6. The findings suggested that, while low-ME diets impaired turkey growth performance, dietary supplementation of DSL could reverse such impacts of these diets. The DSL-supplemented diet at the inclusion level of 2 g/kg was advantageous over both BE and RE diets in terms of intestinal morphology, lipid profile, and antioxidant status in growing turkeys.

Effects of substitution of beet pulp for barley or corn in the diet of high-producing dairy cows on feeding behavior, performance, and ruminal fermentation

This study investigated the effects of substituting beet pulp (BP) for different grains (barley or corn) in the diet of high-producing dairy cows on intake, feeding behavior, nutrient digestibility, ruminal fermentation, milk production, and feed conversion efficiency. Eight second-parity Holstein cows (62 ± 2 d in milk; milk yield = 54 ± 1.2 kg/d; body weight = 624 ± 26; all mean ± SE) were used in a replicated 4 × 4 Latin square design during 4 periods of 21 d. Cows were randomly assigned to 1 of 4 treatments that were a 2 × 2 factorial arrangement of 2 grain sources (corn or barley) and 2 levels of BP inclusion [5 or 15% of dry matter (DM)] in the diet: (1) barley-based diet with BP at 5% of dietary DM; (2) barley-based diet with BP at 15% of dietary DM; (3) corn-based diet with BP at 5% of dietary DM; and (4) corn-based diet with BP at 15% of dietary DM. The increasing amount of BP in the diet was at the expense of decreasing an equal proportion of grain (barley or corn). All diets were high in concentrates (65% of diet DM) and formulated to have similar concentrations of energy and protein. The portion of feedstuffs that is potentially able to be consumed by humans is known as human edible. Accordingly, human-edible protein (HEP) and human-edible energy (HEE) inputs were calculated according to the recommended potential human-edible fraction of each dietary ingredient, and HEP and HEE outputs were determined as the amount of gross energy and true protein in the milk. Feed conversion efficiency (FCE) for HEP and HEE were expressed as output per input of each variable, whereas FCE for the production of fat-corrected milk (FCM) and energy-corrected milk (ECM) were expressed as the amount of each variable per DM intake. Results showed that substituting BP for grain did not affect DM intake, crude protein intake, or nutrient digestibility, whereas starch intake (5.70 vs. 7.43 kg/d for the low-BP vs. high-BP diets, respectively), HEP (2.34 and 1.92 kg/d), and HEE (186 and 147 MJ of gross energy/d) decreased. Treatments did not affect sorting and chewing activities, but increasing BP in the diet increased ruminal pH at 4 h after feeding (6.20 vs. 6.39) and milk fat content (2.92 vs. 3.15%). Similarly, FCE for ECM production (1.44 vs. 1.54) as well as FCE for HEE (0.653 vs. 0.851) and HEP (0.629 vs. 0.702) were greater in high-BP diets compared with low-BP diets. The interaction of BP and grain sources significantly affected FCE for ECM production, where improvements were more evident when BP was substituted for barley than for corn. The improvement in FCE for HEE was greater when BP was substituted for barley (0.236) rather than corn (0.161). In conclusion, the substitution of BP for barley or corn grains in high-concentrate diets of high-producing cows decreased starch intake, increased ruminal pH at 4 h after feeding, and improved FCE for FCM production. Substitution for barley, rather than for corn, promoted greater FCE for ECM production and HEE.

Scolicidal activity of Mesobuthus eupeus venom against the protoscolices of Echinococcus granulosus

Hydatidosis is an important zoonosis caused by a parasitic tapeworm, namely Echinococcus granulosus. This infection is distributed worldwide and affects the health as well as economic loss in both humans and animals. In most cases, the disease needs chemotherapy with or without surgery. Conventional drugs have some major problems, including drug complications, harmful side effects, and also progressive resistance. According to the importance of biological productions as alternative medicine, a large number of studies confirmed that whole venom and many peptide ingredients of the scorpion venom have various different medical benefits, including antimicrobial properties, due to the mechanism of blocking gated ion channel. In this study, the venom peptides of Mesobuthus eupeus scorpionwere purified using gel filtration chromatography and subsequently ion exchange chromatography, followed by the determination of the molecular weights of the proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) procedure. After collecting the hydatid cysts fluids from the liver of infected sheep, protoscolices were derived, washed, and encountered to the whole venom as well as eight different fractions of toxin 30, 60, 120, and 240 min after the exposure. In the next step, the viability of protoscolices was determined by eosin staining. The obtained results revealed that a venom fraction under 10 kDa killed all protoscolices after 30 min. Moreover, it was found that the scolicidal activity of fractions increases according to the time of exposure. As a result, it can be concluded that M. epeus venom peptides under its LD50 (1/2 LD50) can properly and quickly destroy the protoscolices of hydatid cysts at the level of applied concentrations and such components are good alternatives to treat hydatidosis.

Comparison of Relation between Resistance Pattern to Erythromycin and Tetracycline and the Prevalence of Superantigens Coding Enterotoxins A and B in Staphylococcus aureus Isolated from Broiler Poultry in Ilam, Iran

Staphylococcus aureus is a gram-positive coccus that, in specific conditions, is able to generate various diseases. By secreting different enterotoxins, this bacterium prepares the settings to attack the host; among these, enterotoxins A and B play the most important roles in food poisoning. This study was performed to trace the genes coding enterotoxins A and B in Staphylococcus aureus isolated from the clinic and poultry slaughterhouse. In addition, the present study analyzed the relation between the prevalence of these genes and resistance to erythromycin and tetracycline. This study was performed from October 2015 to December 2016. A total of 200 samples of noses and cloaca from broiler poultry farms in Ilam, Iran, were collected, including 150 samples from the slaughterhouse and 50 samples from the clinic isolated for separating Staphylococcus aureus. After bacterial culture and confirmation of biochemical tests, the samples were evaluated for the identification of Staphylococcus aureus and the resistance pattern to antibiotics regarding the presence of femA, tets, ermb, sea, and seb genes using the disk diffusion method and polymerase chain reaction test. Out of 200 tested samples, 112 strains of Staphylococcus aureus (56%) were identified from which 91 and 21 strains were associated with the poultry slaughterhouse and clinic, respectively, and all the samples were identified using biochemical tests. After the detection of femA gene as an exclusive gene for the identification of Staphylococcus aureus strain, 100 strains (50%) were confirmed to be contaminated with this bacterium. Out of 100 strains, 46%, 14%, and 5% possessed the genes coding enterotoxin A, the genes coding enterotoxin B, and both genes, respectively. The results of antibiotic tests showed that 85% and 86% of the examined strains were resistant to erythromycin and tetracycline, respectively. In the present study, the analysis performed using QuickCalcs software showed that the strains resistant to these two antibiotics possessing the sea gene were more prevalent than those possessing seb genes in the samples isolated from the poultry slaughterhouse. This comparison revealed that during the short period of broiler poultry farms growth, resistant strains were able to proliferate sea gene among the herd, and its prevalence increased until reaching into the slaughterhouse. This study showed that the relation between the genes resistant to erythromycin and tetracycline and the sea gene was close and significant.

Humoral and T cell-mediated immune response against trichomoniasis

Trichomonas vaginalis (T. vaginalis) infection leads to the synthesis of specific antibodies in the serum and local secretions. The profile of T. vaginalis-specific antibodies and T cell-mediated immune responses may influence the outcome of infection, towards parasite elimination, persistence or pathological reactions. Studies have indicated that Th1-, Th17- and Th22 cell-related cytokines may be protective or pathogenic, whereas Th2- and Treg cell-related cytokines can exert anti-inflammatory effects during T. vaginalis infection. A number of T. vaginalis-related components such as lipophosphoglycan (TvLPG), α-actinin, migration inhibitory factor (TvMIF), pyruvate:ferredoxin oxidoreductase (PFO), legumain-1 (TvLEGU-1), adhesins and cysteine proteases lead to the induction of specific antibodies. T. vaginalis has acquired several strategies to evade the humoral immune responses such as degradation of immunoglobulins by cysteine proteases, antigenic variation and killing of antibody-producing B cells. The characterization of the T. vaginalis-specific antibodies to significant immunogenic molecules and formulation of strategies to promote their induction in vaginal mucosa may reveal their potential protective effects against trichomoniasis. In this review, we discuss the current understanding of antibody and T cell-mediated immune responses to T. vaginalis and highlight novel insights into the possible role of immune responses in protection against parasite.

Effect of protected-glutamine supplementation on performance, milk composition and some blood metabolites in fresh Holstein cows

The present study was conducted to study the effect of protected-glutamine (Gln) supplementation on dry matter intake (DMI), milk yield (MY) and composition, somatic cell counts (SCC) and blood parameters in fresh cows. Forty Holstein cows at zero day of parturition (calving day = day 0) were divided into four groups (n=10), and fed (ad libitum) with one of the diets including: basal diet (control), basal diet supplemented with 150 (low Gln, LG), 250 (medium Gln, MG) or 350 (high Gln, HG) g of Gln protected with formaldehyde/cow per day. The DMI and MY were recorded from 0 to 21 days post-calving. Milk fat and protein were assessed on days 7, 14 and 21, and blood was collected on days 0, 7, 14, and 21 after parturition. The DMI and MY at 21 days in milk (DIM) in HG group were compared with control (P<0.05). The DMI at 14 and 21 DIM and the MY at 21 DIM were higher in MG group compared with control group (P>0.05). Glucose concentration at 7, 14 and 21 DIM increased in both HG and MG groups compared with control group (P>0.05). The milk SCC of Gln groups was lower (P<0.05) compared with control, at 14 and 21 DIM. Glutamine supplementation increased the blood concentrations of total protein and albumin, but lowered the β-hydoxybutyrate (BHBA), non-esterified fatty acids (NEFA) and aspartate amino transferase (AST) concentrations (P<0.05). These results indicate that rumen protected Gln supplementation at 250 g/heat/day to fresh Holstein cows improved the SCC in milk and health status.

Novel electrodialysis cation exchange membrane prepared by 2-acrylamido-2-methylpropane sulfonic acid; heavy metal ions removal

In the present work a novel heterogeneous cation exchange membrane (CEM) composed of poly vinyl chloride (PVC) and 2-acrylamido-2-methylpropane sulfonic acid based hydrogel (AMAH) was prepared. The membranes were fabricated with different fractions of AMAH to optimize the performance in desalination. The hydrogel was characterized by FT-IR to prove the successful synthesis. The membrane properties such as permselectivity, ionic permeability, flux, water content, electrical resistance, morphology, contact angle and dimensional stability were evaluated. Modified membranes showed acceptable dimensional stabilities, more hydrophilic surface, higher water content and porosity. SEM images revealed the formation of a more porous membrane structure. Membrane permselectivity and transport number showed a relatively constant then decreasing trend in Na⁺ and Ba²⁺ solutions. The experimental results showed that the incorporation of AMAH into the PVC matrix obviously improved ionic permeability and flux of Na (∼9%) and Ba (∼23%). Membrane electrical resistance was declined about 36% by adding AMAH in the membrane structure. Membranes' performance in potassium and heavy metal ions removal showed a remarkable separation capacity of K⁺ (99.9%), Pb²⁺ (99.9%) and Ni²⁺ (96.9%). Membranes showed desirable potential for scaling removal.

Comparison of metformin and N-acetyl cysteine, as an adjuvant to clomiphene citrate, in clomiphene-resistant women with polycystic ovary syndrome

OBJECTIVE

To evaluate the effects of short- and long-term treatment with metformin and NAC, in an adjuvant to clomiphene citrate (CC), on the improvement of hormonal profile (SHBG, total testosterone, FBS, and fasting insulin) and fertility status in CC-resistant women with PCOS.

MATERIALS AND METHODS

One hundred and eight CC-resistant PCOS patients participated in the study and received either metformin (1500mg/day) or NAC (1800mg/day) with 100mg/day of CC for 8 and 12 weeks. Mean BMI, hirsutism score, LH/FSH ratio, endometrial thickness, mature follicle number, and serum concentrations of LH, FSH, E2, fasting insulin, total testosterone and FBS were evaluated before and after short- and long-term treatment. Furthermore, ovulation and pregnancy rates in the first and second cycles were also determined in treated patients.

RESULTS

There was no significant difference in all variables before and 8 weeks after treatment with metformin and NAC. The BMI- and insulin-lowering effects of metformin were significantly higher than NAC after long-term treatment. However, the reducing-effect of NAC on hirsutism score and FBS levels was significantly more than metformin after 12 weeks. Treatment with metformin and NAC significantly increased ovulation and pregnancy rates in CC-resistant PCOS patients. In the first and second cycles, ovulation and pregnancy rates in patients treated with NAC were slightly higher than those received metformin.

CONCLUSIONS

Compared with metformin, administration of NAC in an adjuvant to CC is recommended for improving of hormonal profile and treatment of anovulatory infertility in hyperinsulinemic patients especially women with PCOS who are CC-resistant.

The association of the vitamin D status with the persistence of anti-HBs antibody at 20years after primary vaccination with recombinant hepatitis B vaccine in infancy

BACKGROUND AND OBJECTIVE

Vitamin D has potent immunoregulatory effects due to the expression of its receptor on the majority of immune cells. The aim was to evaluate the association of the vitamin D status with the persistence of anti-HBs antibody and immune response to booster immunization at 20years after primary vaccination with hepatitis B (HB) vaccine.

METHODS

Blood samples were collected from 300 adults 20years after completion of the primary HB vaccination in infancy. The serum levels of vitamin D and anti-HBs antibody were measured by ELISA. A single booster dose of a recombinant HB vaccine was administered to a total of 138 subjects, whose anti-HBs titer was<10IU/L. The sera of revaccinated subjects were re-tested for anti-HBs antibody, 4weeks after booster vaccination.

RESULTS

At 20years after primary vaccination, the mean vitamin D concentrations were significantly higher in seroprotective subjects as compared to non-seroprotective individuals (P<0.01). The levels of anti-HBs were significantly increased with advanced concentrations of vitamin D (P<0.01). Overall, 125/138 (90.6%) of the revaccinated subjects showed an anamnestic response to booster vaccination. The concentrations of vitamin D were significantly higher in subjects with an anamnestic response to booster vaccination as compared with subjects without this response (P<0.01).

CONCLUSION

Vitamin D status may influence the persistence of anti-HBs antibody and durability of protection after primary vaccination with a recombinant HB vaccine in infancy.

Cell-free fetal DNA in amniotic fluid supernatant for prenatal diagnosis

In widespread conviction, amniotic fluid is utilized for prenatal diagnosis. Amniotic fluid supernatant is usually discarded, notwithstanding being a good source of fetal DNA. The aim of the present study was to assess cell-free fetal DNA extracted from amniotic fluid supernatant for application in prenatal diagnosis such as gender determination and early diagnosis of β-thalassemia. Samples of amniotic fluid of 70 pregnant women were collected and went through routine tests along with tests for cell-free fetal DNA from amniotic fluid supernatant. The DNA in the amniotic fluid supernatant was extracted and analyzed for gender determination by PCR and Real-time PCR. ARMS-PCR was applied to test early diagnosis of IVS II-I mutation (common β-thalassemia mutation) and E7V mutation for sickle cell anemia using DNA extracted from the amniotic fluid supernatant. Using the cell-free fetal DNA extracted from the amniotic fluid supernatant, the sensitivity of PCR and Real-time PCR for gender detection was compared with the routine cytogenetic method. The fetus tested for sickle cell anemia and β-thalassemia was observed to be healthy but heterozygous for IVS II-I mutation. The findings indicated that cell-free fetal DNA from amniotic fluid supernatant can be a good source of fetal DNA and be used in early prenatal diagnosis since because of its fast and accurate application. Therefore, it would be suggested that the amniotic fluid supernatant's disposal is prevented because if the tests needs to be repeated, cell-free fetal DNA extracted from the amniotic fluid supernatant can be used as an alternative source for prenatal diagnosis.

Electrodialysis heterogeneous ion exchange membranes modified by SiO2 nanoparticles: fabrication and electrochemical characterization

In the current study mixed matrix heterogeneous cation exchange membranes were prepared by solution casting technique. The effect of SiO(2) nanoparticles in the polymeric solution on the physicochemical properties of prepared membranes was studied. Scanning optical microscope images showed uniform particle distribution and relatively uniform surfaces for the prepared membranes. The membrane water content was reduced by silica nanoparticles in the membranes' matrix. The membrane ion exchange capacity, membrane potential, transport number and selectivity were improved initially by an increase of SiO(2) nanoparticles concentration up to 1%wt in prepared membranes and then showed a decreasing trend with a further increase in additive ratio from 1 to 4%wt. The ionic permeability and flux were also decreased initially by an increase of silica nanoparticles concentration up to 0.5%wt in the membrane matrix and then increased again with a further increase in nanoparticles concentration from 0.5 to 4%wt. Moreover, the results exhibited that using silica nanoparticles in the membrane matrix caused an obvious decrease in areal electrical resistance. The opposite trend was found for membrane mechanical strength using SiO(2) nanoparticles.

Application of full field optical studies for pulsatile flow in a carotid artery phantom

A preliminary comparative measurement between particle imaging velocimetry (PIV) and laser speckle contrast analysis (LASCA) to study pulsatile flow using ventricular assist device in a patient-specific carotid artery phantom is reported. These full-field optical techniques have both been used to study flow and extract complementary parameters. We use the high spatial resolution of PIV to generate a full velocity map of the flow field and the high temporal resolution of LASCA to extract the detailed frequency spectrum of the fluid pulses. Using this combination of techniques a complete study of complex pulsatile flow in an intricate flow network can be studied.

Rumen fermentation, blood metabolites, and growth performance of calves during transition from liquid to solid feed: Effects of dietary level and particle size of alfalfa hay

This study evaluated the effects of particle size (PS) and dietary level of alfalfa hay (AH) on rumen fermentation parameters, blood metabolites, eating behavior, and growth performance in dairy calves during transition from liquid to solid feed. Sixty newborn dairy calves (41 ± 2.5,kg of body weight) were used in a 2 × 2 factorial arrangement with the factors dietary AH level (medium, 12.5%, or high, 25%, on DM basis) and PS (fine = 1mm or medium = 3mm, as geometric means) of AH. Hence, the dietary treatments were (1) medium level of AH with fine PS (M-FPS), (2) medium level of AH with medium PS (M-MPS), (3) high level of AH with fine PS (H-FPS), and (4) high level of AH with medium PS (H-MPS). Particle size of AH did not affect total DMI (TDMI) during the preweaning period, although TDMI was greater for calves fed MPS than in those fed FPS during the postweaning and overall periods. Calves fed MPS spent more time eating solid feed and ruminating and less time on nonnutritive oral behaviors compared with FPS calves. The dietary level of AH did not affect behavioral parameters. Average daily gain of calves was not affected by dietary treatment before weaning. During the postweaning and overall periods, average daily gain was greater in calves fed MPS than in those fed FPS at the 25% AH level, but this effect was absent with 12.5% AH. Furthermore, the rumen pH values on d 35 and 70 of the study were greater for MPS than for FPS, regardless of the dietary level of AH. Effects of AH level, PS, and their interaction did not affect blood glucose concentrations in developing calves. These results indicate that feed intake, feeding behavior, rumen fermentation parameters, and blood β-hydroxybutyrate concentration may be affected by rations differing in forage PS; thus, providing calves with MPS can improve calf performance and reduce their nonnutritive oral behaviors.

Ginger extracts influence the expression of IL-27 and IL-33 in the central nervous system in experimental autoimmune encephalomyelitis and ameliorates the clinical symptoms of disease

The immunomodulatory effects of the IL-27 and IL-33 and the anti-inflammatory effects of ginger have been reported in some studies. The aim was to evaluate the effects of the ginger extract on the expression of IL-27 and IL-33 in a model of experimental autoimmune encephalomyelitis (EAE). In PBS-treated EAE mice the expression of IL-27 P28 was significantly lower whereas the expression of IL-33 was significantly higher than unimmunized control mice. In 200 and 300 mg/kg ginger-treated EAE groups the expression of IL-27 P28 and IL-27 EBI3 was significantly higher whereas the expression of IL-33 was significantly lower than PBS-treated EAE mice. The EAE clinical symptoms and the pathological scores were significantly lower in ginger-treated EAE groups. These results showed that the ginger extract modulates the expression of the IL-27 and IL-33 in the spinal cord of EAE mice and ameliorates the clinical symptoms of disease.

Circulating levels of interleukin-35 in patients with multiple sclerosis: evaluation of the influences of FOXP3 gene polymorphism and treatment program

The regulatory T (Treg) cells play a major role in the control of the autoimmunity and inflammation, and IL-35 has been described as an immunosuppressive cytokine that is mainly produced by CD4(+)FOXP3(+) Treg cells. The aim of this study was to evaluate the serum levels of IL-35 and a single nucleotide polymorphism (SNP), rs3761548, in FOXP3 gene in patients with multiple sclerosis. The blood samples were collected from 140 multiple sclerosis (MS) patients (including 51 untreated and 89 treated patients) and 140 healthy subjects as a control group. The serum levels of IL-35 were measured by ELISA. The DNA was analyzed for SNP rs3761548 in FOXP3 gene using SSP-PCR. There was no significant difference between untreated MS patients and control group regarding the mean serum levels of IL-35, although this parameter was higher in untreated patients. However, the mean serum level of IL-35 in treated MS patients was significantly higher than that in the control group (P < 0.008). The mean serum levels of IL-35 in patients who were treated with interferon-β, methylprednisolone, or with the both interferon-β and methylprednisolone were significantly higher than that in the healthy group (P < 0.01, P < 0.01, and P < 0.2, respectively). The frequencies of AA and AC genotypes at rs3761548 in the FOXP3 gene were significantly higher in MS group as compared with healthy subjects (P < 0.05). The frequency of CC genotype at rs3761548 was significantly lower in the MS group in comparison with healthy control subjects (P < 0.001). Moreover, the frequency of A allele was significantly higher whereas the frequency of C allele was significantly lower in MS patients in comparison to healthy subjects (P < 0.001). The mean serum level of IL-35 was significantly lower in MS patients or healthy subjects with AA genotype as compared with those with CC genotype at rs3761548 in FOXP3 gene (P < 0.01 and P < 0.001, respectively). These results showed higher serum levels of IL-35 in treated MS patients representing that the benefit effects of treatment may in part performed through the upregulation of the IL-35 production. The SNP rs3761548 may influence the susceptibility to MS disease and the serum levels of IL-35.

Dynamic light scattering from pulsatile flow in the presence of induced motion artifacts

Continuous health monitoring has become a major theme of our aging society. Portable devices play an important role here. Many optical portable devices are susceptible to motion induced artifacts. We have performed an experimental study for detection of fluid pulsation based on multi-exposure speckle images, in presence of motion induced artifacts. Induced motion of a wide range of frequencies and amplitudes were generated to resemble sensor motion with respect to skin. The data was analyzed using speckle contrast and correlation. We concluded that both techniques have their own advantages, depending on the measurement configuration. A study of angles between illumination and detection revealed that larger angles yields better signal. Shorter exposure time was more successful in extracting the signal. We also performed in-vivo measurements that agree with the in-vitro case. We also show that a minimum collection of two pixels from the speckle image is sufficient to extract relevant results.

Lower serum level of anti-tetanus toxin antibodies in patients with type 2 diabetes mellitus

AIM

To evaluate the serum levels of anti-tetanus toxin antibodies (anti-TTA) in patients with type 2 diabetes mellitus (DM) and in a control group.

METHODS

Totally, 100 patients with type 2 DM and 100 age- and sex-matched healthy individuals were enrolled to study. The presence of type 2 DM confirmed according to the clinical and para-clinical criteria such as fasting plasma glucose above 126 mg/dl. A peripheral blood sample was collected from all subjects. The serum samples of participants tested for the levels of anti-TTA by ELISA method. The serum antitoxin concentration 0.1 IU/mL was considered as a protective level of antibody.

RESULTS

The seroprotective rate in healthy group was significantly higher than diabetic group (99% vs. 92%; p<0.02). The mean titer of anti-TTA in healthy group (5.32 ± 0.26 IU/ml) was also significantly higher than diabetic patients (3.46 ± 0.26 IU/ml; p>0.001). In diabetic men the mean titer of anti-TTA was significantly higher in comparison to diabetic women (3.94 ± 0.34 IU/ml vs 2.59 ± 0.36 IU/ml; p<0.01). In diabetic patients the seroprotective rate and the mean titer of anti-TTA in subjects with age >40 years was also lower in comparison to those with age <40 years (89.23% vs 97.14%; p<0.15 and 4.57 ± 0.38 IU/ml vs 2.86 ± 0.32 IU/ml; P<0.002, respectively). The mean titer of anti-TTA was significantly higher in patients with diabetes duration <5 years in comparison to patients with disease duration >5 years (3.91 ± 0.35 IU/ml vs 2.85 ± 0.38 IU/ml; p<0.04).

CONCLUSION

these results showed lower levels of anti-TTA in patients with type 2 DM, in diabetic women, in patients aged >40 years and in diabetic patients with disease duration >5 years.

Laser-speckle-based detection of fluid pulsation in the presence of motion artifacts: in vitro and in vivo study

We have performed an in vitro and in vivo study, based on laser speckle contrast analysis, to detect fluid pulsation in the presence of artifacts caused by the relative motion between the sample and the illumination source. We observe that the pulsation signal is clearly detectable for a range of motion amplitudes and oscillation frequencies; however, for higher amplitudes and oscillation frequencies of motion, the signal, due to pulsation, becomes increasingly difficult to detect.

Total leukocyte counts and neutrophil-lymphocyte count ratios among Helicobacter pylori-infected patients with peptic ulcers: independent of bacterial CagA status

Elevated leukocyte counts can be a marker of inflammation and infection. The aim of this study was to determine the total leukocyte count and neutrophil-lymphocyte count ratio (NLCR) among Helicobacter pylori-infected patients with peptic ulcer disease (PU) and among asymptomatic subjects (AS) and to evaluate if there is an association between these lab values and the presence of the H. pylori virulence factor cytotoxin-associated gene A (CagA). Sixty H. pylori-infected PU patients, 63 AS carriers and 32 healthy H. pylori-negative subjects (controls) were included in the study. The total white blood cell (WBC) counts and differentials were determined using standard hematological methods. The mean total WBC count, mean neutrophil count and NLCR were significantly higher among PU patients than in controls (p < 0.001, p < 0.001 and p < 0.001, respectively). Similarly, the mean WBC count, mean neutrophil count and NLCR were significantly higher among AS patients than in controls (p < 0.005, p < 0.001 and p < 0.02, respectively). The differences of mean WBC counts mean neutrophil counts and NLCR were also significantly different (p < 0.005, p < 0.001 and p < 0.001, respectively) between the PU and AS patients. There were no differences in the PU and AS patients in regard to anti-CagA positivity. These results show the CagA factor was not associated with the presence or absence of symptoms in H. pylori infected patients.

Serum levels of interleukin (IL)-27 in patients with ischemic heart disease

OBJECTIVE

Cytokines, the key mediators of immune responses, play an important role in the pathogenesis of cardiovascular diseases. The aim of this study was to evaluate the serum levels of IL-27 in patients with ischemic heart disease (IHD) and also to clarify its association with traditional risk factors of the disease.

METHODS

A total of 120 patients with IHD as having acute myocardial infarction (AMI; n=60) or unstable angina (UA; n=60) and 60 sex- and age-matched healthy subjects as a control group were enrolled in this cross-sectional, case-controlled study. Serum samples were collected from all participants (for AMI patients at 3-5 days after events and for UA at admission time) and tested for the levels of IL-27 by use of ELISA method.

RESULTS

The mean serum levels of IL-27 in AMI group (38.00±14.38 Pg/ml) and UA group (35.77±18.93 Pg/ml) were significantly higher than those observed in the control group (24.91±14.96 Pg/ml; P<0.0001 and 0.001, respectively). The mean serum levels of IL-27 in IHD patients with or without a certain traditional risk factor including hypertension, dyslipidemia, diabetes smoking were significantly higher as compared to those in the control group.

CONCLUSIONS

These results showed that the higher serum levels of IL-27 were associated with IHD. The presence or absence of certain traditional risk factors of IHD did not influence the serum levels of cytokine.

The association between infection burden in Iranian patients with acute myocardial infarction and unstable angina

AIM

to evaluate the association of ischemic heart disease (IHD) with the number of pathogens (infection burden) among individuals with infection.

METHODS

a total of 120 patients with IHD as the acute myocardial infarction (AMI; n=60) or unstable angina (UA; n=60) group and 60 healthy subjects with sex- and age-matched as control group were enrolled in this study. Serum samples of all participants were tested for the presence of antibodies to Helicobacter pylori (H. pylori), cytomegalovirus (CMV), type-1 herpes simplex virus (HSV-1) and type- 2 HSV (HSV-2) by using ELISA.

RESULTS

Regarding the association of the infection burden with IHD, the prevalence ratios and 95% confidence intervals (CI) were 3.18 (CI: 1.50-6.72; P<0.001) for 3 seropositivities and 3.83 (CI: 0.84-17.43; P<0.05) for 4 seropositivities. The rate of subjects with high infection burden (3 seropositivities) was significantly higher in IHD group as compared to control group (53.4% vs 21.6%; P<0.01). Moreover, the mean number of seropositivities was also significantly higher in patients with IHD in comparison to control group (2.47 vs 1.68; P<0.01). The seroprevalence of anti-H. pylori antibodies in AMI and UA groups was significantly higher compared to control group (P<0.0001). The seroprevalence of anti-CMV antibodies in AMI and UA group was also significantly higher than those observed in control group (P<0.01). Moreover, the seroprevalence of anti-HSV-1 antibodies was significantly higher in AMI and UA groups in comparison to control group (P<0.001). The seroprevalence of anti-HSV-2 antibodies was similarly expressed in patients and healthy control group.

CONCLUSION

the infection burden was significantly higher in patients with IHD, which represent that the parameter should also be considered as an independent risk factor for development of IHD. The seroprevalence of H. pylori, CMV and HSV-1 were also higher in patients with IHD.

Serum concentrations of Helicobacter pylori IgG and the virulence factor CagA in patients with ischaemic heart disease

To compare the serum concentrations of IgG to Helicobacter pylori and its virulence factor CagA in patients with ischaemic heart disease (IHD), we recruited 120 patients with IHD [acute myocardial infarction (AMI) (n = 60); unstable angina (UA) (n = 60)] and 60 sex- and age-matched healthy controls in this study. The seroprevalence of anti-H. pylori IgG was 86.7% in AMI, 91.7% in UA patients and 58.3% in the control group with mean titres of 33.2 U/ml [standard error (SE) 4.76], 57.96 U/ml (SE 7.54) and 25.72 U/ml (SE 4.01) respectively. The seroprevalence of anti-H. pylori in the patient groups was significantly higher than the control group. The mean levels of anti-H. pylori in the AMI and UA groups were also significantly higher than in the control group. The seroprevalence and mean titre of anti-CagA IgG did not differ significantly between patient and control groups.

Diagnostic accuracy of Doppler ultrasonography in differentiation between malignant and benign cervical lymphadenopathies in pediatric age group

Cervical lymphadenopathy is a relatively common finding in pediatric age group and is caused by a wide spectrum of diseases from transient infections to malignancies especially lymphomas. The present study was aimed at evaluating the diagnostic performance of grey-scale ultrasonography, color Doppler ultrasonography and power Doppler ultrasonography in differentiation of reactively and metastatically enlarged cervical lymph nodes in pediatric age group. Fifty children with cervical lymphadenopathies were assessed by ultrasonographic methods. In each patient, the longest (L) and transverse (T) diameters, L/T ratio and presence or absence of the normal hilar pattern were checked by grey-scale ultrasonography. Spectral parameters (resistive and pulsatility indices) and vascular distribution pattern of nodes were recorded by color and power Doppler ultrasonography, respectively. Following the ultrasonographic evaluations, biopsy and/or clinical follow up was applied for six months, based on the clinical and paraclinical findings. Statistical analyses were performed by chi-square test, independent t-test and receiver operator characteristic curves. The mean age of patients was 12.42 +/- 2.42 years. Twenty eight patients (56%) had malignant enlargement of lymph nodes. The mean value of L/T ratio in malignant group was 1.70 +/- 0.22 and 2.40 +/- 0.38 in non-malignant nodes (p < 0.001). Sensitivity, specificity and accuracy of combined grey-scale and power Doppler ultrasonography were 70, 86 and 81%, respectively. Combination of grey-scale and power Doppler ultrasonography is recommended for the differentiation between the malignant and benign lymphadenopathies in children. Moreover, our findings revealed no diagnostic role of color Doppler ultrasonography in the selection of malignant cervical lymph nodes in children.

Oxidation of phenol in a bioremediation medium using Fenton's reagent

The oxidation of phenol by Fenton's reagent was investigated in a medium suitable for bioremediation. An experimental design approach, based on a central composite rotatable design, was used to quantify the effects of H2O2 concentration (2000 to 5000 mg 1(-1)) and FeSO4.7H2O concentration (500 to 2000 mg 1(-1)). Performance of the chemical oxidation by Fenton's reagent was evaluated by determining the percentage of phenol oxidized at equilibrium. The analysis of variance test indicated that both H2O2 and FeSO4.7H2O concentrations had a positive effect on phenol oxidation. Hydrogen peroxide concentration was the dominating parameter for the removal of phenol by Fenton's reagent. The optimal concentrations of H2O2 and FeSO4.7H2O for complete oxidation of 2000 mg 1(-1) phenol in the medium were found to be 4340 mg 1(-1) and 1616 mg 1(-1), respectively, at 25 degrees C and pH 3. Oxidation of phenol in the culture medium was found to be significantly different than in pure water.

Serum levels of high-sensitivity C-reactive protein (hs-CRP)in Helicobacter pylori-infected peptic ulcer patients and its association with bacterial CagA virulence factor

OBJECTIVE

CRP is a marker of inflammation and infection of the gastric mucosa with Helicobacter pylori, which causes an inflammatory reaction. It has been reported that CagA(+) H. pylori strains induce more severe gastric inflammation and are also associated with higher risks of peptic ulcer and gastric cancer. The purpose of this study was to compare serum concentrations of hs-CRP in H. pylori-infected peptic ulcer (PU) patients, H. pylori infected asymptomatic (AS) carriers, and a healthy control group, and their association with bacterial virulence factor CagA.

MATERIAL AND METHODS

A total of 60 H. pylori infected PU patients (30 patients were positive for anti-CagA antibody and 30 were negative for anti-CagA antibody), 53 H. pylori-infected AS carriers (25 subjects were positive for anti-CagA antibody and 28 were negative for anti-CagA antibody), and 22 healthy H. pylori-negative subjects (as a control group) were enrolled in the study. Serum concentrations of hs-CRP were measured by use of an ELISA method.

RESULTS

The mean serum level of hs-CRP in all PU patients (124.9±32.4 μg/dl) was significantly higher than that in all AS subjects (18.6±2.6 μg/dl; P<0.001) and the healthy uninfected control group (10.7±2.9 μg/dl; P<0.0001). Moreover, the mean serum level of hs-CRP in the AS group was significantly higher than that observed in the uninfected control group (P<0.04). No significant difference was observed between mean serum levels of hs-CRP of PU patients with positive test for anti-CagA antibody (132.6±49.4 μg/dl) and PU patients with negative test for anti-CagA antibody (117.1±42.9 μg/dl). Moreover, mean serum levels of hs-CRP were similar in AS subjects with positive test for anti-CagA (18.4±3.1 μg/dl) and in those who were negative for anti-CagA antibody (18.9±4.1 μg/dl).

CONCLUSION

The results of this study showed that mean serum concentrations of hs-CRP in PU patients and in H. pylori infected AS carriers were higher than in a healthy control group. Although H. pylori infection is associated with higher serum levels of hs-CRP, serum concentrations of this inflammatory marker were not affected by expression of bacterial CagA virulence factor.

Ultrasound findings in biliary atresia: the role of triangular cord sign

In this prospective study, 49 infants with prolonged jaundice, were studied between January 2005 to April 2007 in Tabriz Children's Hospital. All of these infants were evaluated with ultrasonography and isotopscan and finally biopsy was done in all of them under guide of sonography. In their sonographic evaluation, absence or presence of gall bladder, its size and also its evacuation after feeding was checked and beside this triangular cord sign was controlled. The PPV and specificity of triangular cord sign in diagnosis of extrahepatic biliary atresia (EHBA) was 100% but its NPV was only 78.5%. The overall accuracy, PPV, NPV, specificity and sensitivity ofultrasonographic findings in diagnosis of EHBA was about 94, 92, 94, 97 and 86%. Ultrasonography is a reliable screening method in early diagnosis of EHBA and triangular cord sign increases its accuracy especially its specificity.

Screening of bovine coagulase-negative staphylococci from milk for superantigen-encoding genes

A collection of 102 coagulase-negative staphylococci (CNS), isolated from cases of subclinical and clinical bovine mastitis and belonging to 10 different species, were screened by PCR for the presence of genes encoding enterotoxins and enterotoxin-like toxins (sea, seb, sec, sed, see, seg, seh, sei, sej, selk, sell, selm, seln, selo, selp, selq and selu), toxic shock syndrome toxin-1 (tst), and exfoliative toxins A and B (eta and etb). No toxin gene sequences were amplified from any of the isolates, indicating that superantigens encoded by genes detectable by the PCR tests used were not involved in the development of subclinical and clinical mastitis in cattle infected with the CNS isolates tested.

Specific serum immunoglobulin G to H pylori and CagA in healthy children and adults (south-east of Iran)

AIM: To evaluate the serologic IgG response to H pylori and CagA across age groups and in healthy children and adults.

METHODS: Totally, 386 children aged 1-15 years and 200 adults aged 20-60 years, were enrolled to study. The serum samples of participant were tested for presence of anti-H pylori and anti-CagA IgG by using ELISA method.

RESULTS: The seroprevalence of H pylori in adults was significantly higher than that observed in children (67.5% vs 46.6%; P < 0.000003). In children, the seropositivity rate in males (51.9%) was significantly (P < 0.05) higher than that observed in females (41.7%). The prevalence of serum anti-CagA antibody was 72.8% and 67.4% in infected children and adults, respectively. The mean titer of serum anti-CagA antibodies was significantly higher among children in comparison to adults (64.1 Uarb/mL vs 30.7; P < 0.03). In infected children and adults the prevalence of serum anti-CagA antibody was higher in males compared to females (78.4% vs 66.3%; P = 0.07 and 75.6% vs 54.71%; P < 0.04, respectively). The age-specific prevalence of anti-H pylori and anti-CagA antibody (in infected subjects) was 37.6% and 59.57% at age 1-5 years, 46.9% and 75% at age 6-10 years, 54.9% and 79.45% at age 11-15, 59.01% and 83.33% at age 20-30 years, 66.6% and 60.52% at age 31-40 years, 73.46% and 63.88% at age 41-50 years and 75.75% and 60% at age 51-60 years with mean titer of anti-CagA antibody of 75.94, 63.32, 57.11, 52.06, 23.62, 21.52 and 21.80 Uarb/mL, respectively. There was significant difference between mean serum anti-CagA antibody in age subgroups (P < 0.001).

CONCLUSION: These results showed that anti-H pylori and anti-CagA antibodies were common in the children and adults. The H pylori-specific antibodies influenced by age and sex of subjects. Moreover, it seems that males are more susceptible to infection with CagA⁺ strains compared to females. The seroprevalence of anti-CagA antibody was increased with age, up to 30 years and then decreased. It was also found that the magnitude of the IgG response to CagA decreased with advanced age.

Urinary iodine excretion and antiperoxidase enzyme antibody in goitrous and healthy primary school children of Arak, Iran

OBJECTIVE

To determine urinary iodine excretion (UIE) and antiperoxidase enzyme antibody (anti-TPO Ab) in primary school-age children living in Arak, Iran, in 2005, after 10 yr of iodized salt distribution in an effort to ameliorate iodine deficiency.

METHODS

Through an observational, case-control study and by means of satisfied sampling, 6520 primary school children were examined for goiter, and then 193 goiterous children (case) and 151 healthy (control) children were assessed as representative samples for thyroid function tests, antiperoxidase antibody, and urinary iodine excretion. Normal values of anti-TPO Ab were <40 U/ml and high values >75 U/ml. Normal values of urinary iodine concentration were > or =10.0 microg/dl, and severe iodine deficiency were <2 microg/dl. The data were analyzed and compared by the Chi- Square tests and Mann-Whitney U in SPSS software; p-values <0.05 were considered statistically significant.

RESULTS

Total mean prevalence of goiter was 5.2%, ranging from 3.6 to 6.4% in different schools. The prevalence of goiter increased with age; it was 3% in children aged 6-7 yr and 6.3% in children aged 11 yr (p<0.001). Mean iodine urinary concentration was 16.36 microg/dl (+/-1.58). No difference was seen between the mean urinary iodine in girls (17.30+/-3.80 micorg/dl) and boys (15.72+/-2.72 microg/dl). No difference was seen between the mean urinary iodine in goiterous and healthy school children (17.4+/-3.7 microg/dl vs 15.3+/-3.18 microg/dl, p=0.78). About 49.5% of school children had UIE<10 microg/dl and 28% had UIE<5 microg/dl. High levels of anti-TPO Ab were found in 21 school children (18 goiterous vs 3 healthy children, p=0.01) resulting in a total prevalence of 6.1%. In females, the prevalence was 1.3 times higher than in males (male:female ratio 3/4). Thirteen out of 21 (62%) children with positive antibodies had significant goiter (grade 2), and 5 (24%) had small goiter (grade 1), whereas only 3 children (14%) had normal thyroid size (p=0.001).

CONCLUSION

If urinary iodine concentration is considered an index of total body iodine content, this study demonstrated that prolonged iodized salt intake has minimized the occurrence of iodine deficiency goiter and now autoimmune thyroid enlargement is one cause for continuous goiter in primary school children, although there are unknown etiologies that need to be considered in further studies.

Batch and continuous biooxidation of sulphide by Thiomicrospira sp. CVO: reaction kinetics and stoichiometry

Aqueous phase biooxidation of sulphide by the novel sulphide-oxidizing bacterium Thiomicrospira sp. CVO was studied in batch and continuous systems. CVO was able to oxidize sulphide at concentrations as high as 19 mM. Sulphide biooxidation occurred in two distinct phases, one resulting in the formation of sulphur and possibly other dissolved sulphur compounds rather than sulphate, followed by sulphate formation. The specific growth rate of CVO in the first and second phases were 0.17-0.27 and 0.04-0.05 h(-1), respectively. Nitrite accumulated in the culture during the first phase and was consumed during the second phase. The composition of end-products was influenced by the ratio of sulphide to nitrate initial concentrations. At a ratio of 0.28, sulphate represented 93% of the reaction products, while with a ratio of 1.6 the conversion of sulphide to sulphate was only 9.3%. In the continuous bioreactor, complete removal of sulphide was observed at sulphide volumetric loading rates as high as 1.6mM/h (residence time of 10h). Overall sulphide removal efficiency decreased continuously upon further increases in volumetric loading rate. However, the volumetric removal rate increased until a maximum value of 2.4mM/h was obtained at a loading rate of 3.2mM/h. The corresponding sulphide conversion and residence time were 76% and 5.6h, respectively. As expected from the high ratio of sulphide to nitrate loading rates (1.7-1.9 mM/h), no sulphate was formed in the continuous reactor. Using the experimental data the value of maximum specific growth rate, saturation constant, decay coefficient, maintenance coefficient and yield were determined to be 0.36 h(-1), 1.99 mM sulphide, 0.0014 h(-1), 0.078 mmol sulphide/mg ATPh and 0.018 mg ATP/mmol sulphide, respectively.

Dynamics of corrosion rates associated with nitrite or nitrate mediated control of souring under biological conditions simulating an oil reservoir

Representative microbial cultures from an oil reservoir and electrochemical techniques including potentiodynamic scan and linear polarization were used to investigate the time dependent corrosion rate associated with control of biogenic sulphide production through addition of nitrite, nitrate and a combination of nitrate-reducing, sulphide-oxidizing bacteria (NR-SOB) and nitrate. The addition of nitrate alone did not prevent the biogenic production of sulphide but the produced sulphide was eventually oxidized and removed from the system. The addition of nitrate and NR-SOB had a similar effect on oxidation and removal of sulphide present in the system. However, as the addition of nitrate and NR-SOB was performed towards the end of sulphide production phase, the assessment of immediate impact was not possible. The addition of nitrite inhibited the biogenic production of sulphide immediately and led to removal of sulphide through nitrite mediated chemical oxidation of sulphide. The real time corrosion rate measurement revealed that in all three cases an acceleration in the corrosion rate occurred during the oxidation and removal of sulphide. Amendments of nitrate and NR-SOB or nitrate alone both gave rise to localized corrosion in the form of pits, with the maximum observed corrosion rates of 0.72 and 1.4 mm year(-1), respectively. The addition of nitrite also accelerated the corrosion rate but the maximum corrosion rate observed following nitrite addition was 0.3 mm year(-1). Furthermore, in the presence of nitrite the extent of pitting was not as high as those observed with other control methods.

Enhancement of indomethacin-induced gastric damage by mouth breathing in rabbits

Previous studies have reported that mouth breathing is associated with respiratory acidosis. Regarding to the reports that renal elimination of weak acids such as indomethacin is pH dependent, this study was carried out to evaluate the role of mouth breathing on plasma level of indomethacin and indomethacin-induced gastric damage in rabbits. Mouth breathing was induced by surgical ligation of nostrils under general anesthesia. One day after the operation, arterial blood samples were collected for acid-base balance analysis and indomethacin was administered intraperitoneally in a single dose of 40mg/kg. The animals were killed 4h after indomethacin administration and blood samples were collected for spectrofluorometric determination of indomethacin in plasma. The results showed that indomethacin induces more severe gastric damage in nose obstructed rabbits compared with sham and unoperated (UNOP) animals. Acid-base analysis revealed a respiratory acidosis in nose obstructed rabbits and indomethacin level of plasma was significantly higher in nose obstructed animals in comparison with control rabbits. The study shows that mouth breathing can increase the potentiation of indomethacin-induced gastric mucosal damage that may be due to higher level of indomethacin in plasma of nose obstructed animals.

Differentiation of bovine and porcine gelatins using principal component analysis

Gelatin is a collagen derivative, which has a large application in the pharmaceutical, food and adhesive industries as well as photography. The large similarity in structure and properties of gelatins from different origins makes their differentiation difficult. Certain chemometric methods, such as principal component analysis (PCA), can help to classify and characterize gelatin components. In this study 14 bovine and 5 porcine gelatins were examined. The analysis procedure involved complete hydrolysis of samples by classic acid hydrolysis in order to release their amino acid residues. Separation and determination of amino acids was achieved by reversed-phase (RP) HPLC following pre-column derivatisation. Orthophtaldialdehyde (OPA) and 4-chloro-7-nitro benzofurazane (NBD-Cl) were used as derivatisation reagents. From the 20 peaks detected by HPLC analysis, one was very typical in bovine gelatin. Peak height, area, area percentage and width were used to make matrixes. Principal component analysis with the MATLAB program was used to differentiate these gelatins. PCA on matrix of height, width and total matrix were resulted in good differentiation between bovine and porcine gelatins.

Nitrite reductase activity of sulphate-reducing bacteria prevents their inhibition by nitrate-reducing, sulphide-oxidizing bacteria

Sulphate-reducing bacteria (SRB) can be inhibited by nitrate-reducing, sulphide-oxidizing bacteria (NR-SOB), despite the fact that these two groups are interdependent in many anaerobic environments. Practical applications of this inhibition include the reduction of sulphide concentrations in oil fields by nitrate injection. The NR-SOB Thiomicrospira sp. strain CVO was found to oxidize up to 15 mM sulphide, considerably more than three other NR-SOB strains that were tested. Sulphide oxidation increased the environmental redox potential (Eh) from -400 to +100 mV and gave 0.6 nitrite per nitrate reduced. Within the genus Desulfovibrio, strains Lac3 and Lac6 were inhibited by strain CVO and nitrate for the duration of the experiment, whereas inhibition of strains Lac15 and D. vulgaris Hildenborough was transient. The latter had very high nitrite reductase (Nrf) activity. Southern blotting with D. vulgaris nrf genes as a probe indicated the absence of homologous nrf genes from strains Lac3 and Lac6 and their presence in strain Lac15. With respect to SRB from other genera, inhibition of the known nitrite reducer Desulfobulbus propionicus by strain CVO and nitrate was transient, whereas inhibition of Desulfobacterium autotrophicum and Desulfobacter postgatei was long-lasting. The results indicate that inhibition of SRB by NR-SOB is caused by nitrite production. Nrf-containing SRB can overcome this inhibition by further reducing nitrite to ammonia, preventing a stalling of the favourable metabolic interactions between these two bacterial groups. Nrf, which is widely distributed in SRB, can thus be regarded as a resistance factor that prevents the inhibition of dissimilatory sulphate reduction by nitrite.