Mucosal vs. cutaneous advancement flaps for the treatment of chronic anal fissures: a randomized clinical trial.

PURPOSE: The aim of this study was to compare two surgical treatment methods for chronic anal fissures (CAF), mucosal advancement flap anoplasty (MAFA) and cutaneous advancement flap anoplasty (CAFA). METHODS: A randomized, blinded clinical trial was conducted on patients with CAF refractory to medical treatment referred to a tertiary-level hospital between January 2021 and December 2022. The patients were assigned to two groups by block randomization and were compared in terms of outcome, pain reduction, and complications. RESULTS: There were 30 patients (male to female ratio 2:3, median age 42 years [range 25-59 years]). Both techniques reduced anal pain significantly (p = 0.001); however, there were no significant differences between MAFA and CAFA groups in recurrence, duration of healing, postoperative pain, and postoperative bleeding. No patient suffered from fecal incontinence (Wexner score = 0) or flap necrosis postoperatively. Only two patients in the MAFA group (1 and 3 months after surgery) and one patient in the CAFA group (2 months after surgery) had recurrence (total recurrence rate = 10%, healing rate = 90%). All of the patients were satisfied with their surgical results. CONCLUSION: Mucosal and cutaneous anal advancement flap techniques are effective and comparable surgical procedures for the treatment of chronic anal fissures with minimal complications, fast healing process, and minimal postoperative pain and complications. CLINICAL TRIAL ID: IRCT20120129008861N4 ( www.irct.ir ).

Synergistic effects of probiotic Bifidobacterium isolated from chicken's intestine in combination with polyvinylpyrrolidone on reduction of aflatoxin B1.

Food contamination with aflatoxin is one of the most critical concerns of health professionals. One of the best ways to reduce aflatoxin content in food is probiotics. Therefore, this study was performed to isolate Bifidobacterium from the chick's intestine; evaluate its probiotic activities and its application with Polyvinylpyrrolidone (PVP) to reduce aflatoxin B1 (AFB1 ) in the medium were investigated. Samples were isolated from the chick's intestine, and Bifidobacterium was isolated and identified by biochemical and molecular methods. Next, the potential probiotic characterization was assessed. Afterwards, the effect of selected isolate and PVP on reducing AFB1 in the medium was studied using ELISA and HPLC. Biochemical and molecular evaluations indicated isolation of Bifidobacterium bifidum strain from chick's intestine. One of the B. bifidum strains was selected for the next steps, which showed potential probiotic characterization and the ability to reduce the concentration of AFB1 in the medium (50% reduction). When used in combination with PVP showed synergistic effects in reducing the concentration of AFB1 from the medium (up to 90%). In the conclusion, it was found that selected B. bifidum strains and PVP could have synergistic effects in reducing AFB1 toxin in a medium up to 90%.

Characteristics of methicillin-resistant Staphylococcus aureus carrying the toxic shock syndrome toxin gene: high prevalence of clonal complex 22 strains and the emergence of new spa types t223 and t605 in Iran.

Methicillin-resistant Staphylococcus aureus (MRSA) strains that carry the tst gene are disseminated worldwide with varying regional incidences and different genetic backgrounds. The data on molecular characteristics of these strains is insufficient in Iran. The present study aimed to assess the characteristics and distribution of spa types of tst-positive MRSA strains. We investigated 89 MRSA isolates carrying the tst gene with spa typing, resistance gene detection and in vitro antimicrobial susceptibility. Of the 89 tested isolates, 61 (68.5%) were confirmed as multidrug resistant (MDR). The isolates were distributed across seven clonal complexes (CCs) including CC22 (42.7%), CC8 (28.1%), CC5 (11.2%), CC59 (5.6%), CC30 (4.5%), CC80 (4.5%) and CC15 (3.4%). spa typing identified 11 distinct types, with t223 (16.9%) and t790 (15.7%) being the most prevalent. All high-level mupirocin-resistant strains belonged to t002 (n = 8) and low-level mupirocin-resistant strains belonged to t790 (n = 6) spa types. Fusidic-acid-resistant isolates belonged to t437 (n = 3). iMLSB phenotype was observed in t005 (6.7%), t002 (5.6%), t790 (3.4%), and t030, t044 and t084 (each 2.2%). It was found that in the tst-carrying MRSA strains, there were genetic diversities with a majority of the t223 spa type. Indeed, there is a necessity for more constructive surveillance/infection control strategies to address the prevalence and prevention of the emerging spa types.

Carriage of Class 1 and Class 2 Integron in Multidrug Resistant Pseudomonas aeruginosa Isolated from Burn Patients in Tehran Hospitals, Iran.

OBJECTIVE: To investigate the antimicrobial susceptibility patterns of Pseudomonas aeruginosa clinical isolates and their associations with the existence of integrons. METHODS: During a 12-month study, 140 clinically significant Pseudomonas aeruginosa isolates were collected from patients hospitalized in the burn ward of different hospitals in Tehran. Pseudomonas aeruginosa isolates were identified using standard laboratory procedures. Antimicrobial susceptibility testing was performed for 13 antimicrobial agents according to the standard Kirby-Bauer disk diffusion method and Clinical and Laboratory Standards Institute (CLSI) guidelines. The frequency of Class 1, 2 and 3 integrons was detected using a polymerase chain reaction (PCR) method. RESULTS: The resistance rates of Pseudomonas aeruginosa isolates to 13 antimicrobial agents were between 34.7% and 90.8%. Ceftriaxone and imipenem had good activity against the isolates. Of 140 tested isolates, 91 (65%) were multidrug resistant. The most predominant resistance profile among the isolates included resistance to 10 (12.14%), 9 (12.14%) and 8 (12.14%) antibiotics. Class 1 and 2 integrons were detected in 57.2% (56/98) and 30.6% (30/98) of tested Pseudomonas aeruginosa isolates, respectively. Of 98 (70%) integron positive isolates, only 12 (12.2%) isolates were positive for both classes of integrons. Resistance of the isolates to cefotaxime, aztreonam, imipenem, tobramycin, ticarcillin, ciprofloxacin and cloxacillin was observed to be significantly associated with the existence of integrons. CONCLUSION: These data confirmed high prevalence of Class 1 integrons among Pseudomonas aeruginosa isolates from burn patients in this study. Based on these results, integrons may play an important role in the possible transmission of resistance genes to the clinical Pseudomonas aeruginosa isolates.

Effect of uterine lavage on neutrophil counts in postpartum dairy cows.

Subclinical endometritis affects approximately 30% of lactating dairy cows, causing significant economic losses to the dairy industry. Yet, there is no efficient treatment available for this condition. The present study examines the effect of uterine lavage in clinically normal cows with sterile saline solution at 30 days in milk (DIM) on the percentage of polymorphonuclear cells (PMNs) detected with endometrial cytology as an indicator of subclinical endometritis. It was hypothesized uterine lavage would be a technique to reduce the number of PMNs in the uterus, and hence be beneficial for cows affected by subclinical endometritis. Cytology samples were taken by low-volume flushing from 50 Holstein Friesian cows on 30 and 40 DIM. On Day 30, cows were clinically examined and randomly assigned into a treatment and control group. In the treatment group, the cytology sampling on Day 30 was immediately followed by uterine lavage with 500-600 mL of sterile physiological saline (35-40°C). Cytology sampling was repeated in all cows at 40 DIM. Lactation numbers >2, peripheral progesterone concentrations >1 ng/mL and uterine lavage at 30 DIM all were significantly associated with lesser PMN percentages at 40 DIM (P=0.0041; 0.0187 and 0.0043, respectively). Uterine lavage might, therefore, be a useful and practical method to decrease the number of PMNs in the uterus of cattle. Results from the current study can be used as preliminary data for designing in depth therapeutic protocols for treatment of subclinical endometritis in cattle.

Doxorubicin Cytotoxicity in Combination with Soy Isoflavone Daidzein on MCF-7 Breast Cancer Cells

Introduction: Combination chemotherapy regimens offer a promising approach to the prevention of recurrence, metastasis and drug resistance during breast cancer management. Combined tumor therapy using natural substances is highly suggested. Daidzein is one of the major isoflavones in soy beans with anti-tumor activity but its effect in combination with common chemotherapeutic agents is still unclear. This study was designed to investigate whether daidzein increases the antitumor activity of doxorubicin against MCF-7 human breast cancer cells. Methods: The cytotoxic activity of doxorubicin, daidzein and a combination of the two drugs was determined at different concentrations using LDH release assay. The average values of each experiment were adjusted to the values determined from untreated controls and 50% inhibitory concentration (IC.) value for each drug was calculated by CompuSyn. In vitro interaction was also calculated using different combinations of doxorubicin and daidzein. Combination indices (CI) were calculated and combination index plot was constructed using the same software. Results: Analysis of the dose-effect curve showed that the treatment of MCF-7 cells with doxorubicin or daidzein for 24 h led to 50% cytotoxicity at 5.4 nM and 146.5 respectively. Conclusion: The Combination index plot showed CI >1 for all combinations used in this study which indicates antagonistic interactions between daidzein and doxorubicin. This study results have implications for patients with breast cancer under treatment with doxorubicin if they are taking daidzein as a dietary supplement.

HSP70 modified response against HPV based tumor.

BACKGROUND AND OBJECTIVES: DNA immunization is quite inventive vaccination strategies that engage the direct introduction of plasmid DNA encoding the desired antigen into the host. DNA vaccines expand strong protective responses against tumors. The desired target E7 oncogene products represent a target of choice for the therapeutic vaccination. The efficacy of vaccination is limited and it is often necessary to enhance the immune response by using adjuvant in order to achieve the desired responses. Numerous approaches have been applied to boost the effectiveness, such as the fusion or co-administration of cytokine and co-stimulatory molecules gene. Heat-shock protein 70 a family of chaperone proteins makes possible delivery of non-covalently bound peptide to MHC I molecules and influences peptide-specific CTL responses and cure treated individuals. HSP70 have been proposed as the affective adjuvant and expected to act as an appropriate substitute of both cytokine and co-stimulatory genes. MATERIALS AND METHODS: In the current study, the impact of HSP70 co-delivery and HPV-E7 boosting on cellular immune responses and protection has been investigated by intramuscular injection of mixed DNA constructs. RESULTS: Our results reveal that the target DNA vaccine can influence an E7-specific CTL response, which is imperative in the lysis of infected tumor cells, compared to negative control (p < 0.05). Additionally, treatment of tumor-bearing mice with pcDNA/E7 + HSP70 plasmid generates stronger immune responses and decreased significantly tumor sizes. Immunization with HSP-based vaccine with special target immunogene can induce potent and specific anti-tumor or anti-viral immune responses. CONCLUSIONS: Co-administration of pcDNA/E7 + HSP70 plasmid was immunologically more effective than pcDNA/E7 alone. It was concluded that all the characteristics observed during our investigation demonstrate the potent adjuvant activities of HSP70 and could be an efficient approach to persuade dramatically E7-specific immune responses as future cervical cancer vaccine.  

Effect of probiotication on antioxidant and antibacterial activities of pomegranate juices from sour and sweet cultivars.

There is an increasing interest in using pomegranate juice as a natural antioxidant rather than synthetic compounds. In this study, the antioxidant capacities of probioticated and nonprobioticated aril juices of sweet (SWV) and sour (SV) pomegranate cultivars were determined by two different methods: ferric reducing antioxidant power (FRAP) and 1,1-diphenyl 2-picrylhydrazyl assay. Total counts of Lactobacillus casei GG increased by about 3 log in SWV and 2 log in SV juices after incubation for 48 h. Probiotication improved the antioxidant activity of SWV juice from 74.4% to 91.82%, and SV juice from 82.64% to 97.8%. Based on the FRAP value, the reducing power of the probioticated pomegranate juices was also much stronger than the nonprobioticated juices. The FRAP values for SWV and SV probioticated juices were 97.34 and 120.7 mmol L(-1), respectively, which were notably higher than 85.87 and 93.4 mmol L(-1) for SWV and SV nonprobioticated juices. Both fermentated and nonfermentated juices exhibited a potent and wide-spectrum antibacterial effect, with the highest activity against Pseudomonas aeruginosa. SV juice showed wider zones of growth inhibition. The results of this study verify for the first time that probiotication of SWV and SV pomegranate juices can add to their beneficial antioxidant activities.

Cadmium chloride exhibits a profound toxic effect on bacterial microflora of the mice gastrointestinal tract.

Cadmium (Cd²(+)), a naturally occurring heavy metal, is an important environmental pollutant and a potent toxicant to bacteria. The gastrointestinal (GI) tract microflora has a marked capacity to cope with the increased load of ingested metals. However, heavy metals may have harmful effects on GIT microflora. Under the conditions of experimental exposure to cadmium, changes in the population of intestinal microflora in healthy mice were examined. Five experimental groups received 23 to 50 mg kg⁻¹ cadmium in drinking water and control group was given water free from cadmium for 45 days. Intestinal contents and biopsy samples were aseptically collected and bacterial counts were performed. The microflora of the intestine in control group was represented by bacteria of the genera Bacillus cereus, Lactobacillus spp., Clostridium spp., Escherichia coli, Klebsiella spp., Pseudomonas spp., Enterococcus spp. and Proteus spp. As the result of dysbiosis induced by the introduction of cadmium, a sharp decrease in the population of all microbial species in the intestine was observed. The deleterious effect of cadmium appeared to be less in the large intestine and rectum than that of small intestine, suggesting a site-specific influence of cadmium. The gram-negative bacteria tested were less sensitive to cadmium compared to the gram-positive bacteria because of their possible different ability to uptake the metal ions.

Effect of feeding a docosahexaenoic acid-enriched nutriceutical on the quality of fresh and frozen-thawed semen in Holstein bulls.

The aim of the current study was to investigate the effect of feeding a DHA-enriched nutriceutical on the in vitro quality and sperm motility parameters of fresh and frozen-thawed bull semen assessed by CASA. Samples were obtained from nineteen Holstein bulls used for semen collection at Semen Production Center, Karaj, Iran. Control group (n = 10) were fed a standard concentrate feed while treatment group bulls (n = 9) had this standard feed top dressed with 100 g of a commercially available DHA-enriched nutriceutical. Semen quality was assessed on ejaculates collected at the baseline and after 5, 9, and 12 weeks of supplementation. Classical semen evaluation, assessment of sperm motility (subjective and computer-assisted), viability (eosin-nigrosin), and hypo-osmotic swelling test (HOST) were conducted. Semen volume, sperm concentration, and consequently total sperm output were not affected by dietary treatment (P > 0.05). Feeding the nutriceutical was indeed found to affect sperm motility parameters assessed by CASA after 9 weeks of trial. The treatment has improved total motility (P < 0.01), progressive motility (P < 0.05), average path velocity (P < 0.05), HOST-positive (P < 0.01), and proportion of rapid spermatozoa (P < 0.01) in the fresh semen of bulls. Moreover, the proportion of viable spermatozoa increased (P < 0.05) in the ejaculates collected from nutriceutical-fed bulls compared to the control after 12 weeks of feeding trial. The post-thawed HOST and sperm motility data obtained by CASA did not differ between two groups (P > 0.05). On the other hand, dietary supplementation did not affect body weight, BCS and scrotal circumference. Consequently, it can be concluded that dietary DHA supplementation or its precursors, improve in vitro quality and motility parameters of fresh semen assessed by CASA in Holstein bulls. However, this effect was not pronounced in frozen-thawed semen.

Selection for autochthonous bifidobacteial isolates adapted to simulated gastrointestinal fluid.

BACKGROUND AND THE PURPOSE OF THE STUDY: Bifidobacterial strains are excessively sensitive to acidic conditions and this can affect their living ability in the stomach and fermented foods, and as a result, restrict their use as live probiotic cultures. The aim of the present study was to obtain bifidobacterial isolates with augmented tolerance to simulated gastrointestinal condition using cross-protection method. METHODS: Individual bifidobacterial strains were treated in acidic environment and also in media containing bile salts and NaCl. Viability of the acid and acid-bile-NaCl tolerant isolates was further examined in simulated gastric and small intestine by subsequent incubation of the probiotic bacteria in the corresponding media for 120 min. Antipathogenic activities of the adapted isolates were compared with those of the original strains. RESULTS AND MAJOR CONCLUSION: The acid and acid-bile-NaCl adapted isolates showed improved viabilities significantly (p<0.05) in simulated gastric fluid compared to their parent strains. The levels of reduction in bacterial count (Log cfu/ml) of the acid and acid-bile-NaCl adapted isolates obtained in simulated gastric fluid ranged from 0.64-3.06 and 0.36-2.43 logarithmic units after 120 min of incubation. There was no significant difference between the viability of the acid-bile-NaCl-tolerant isolates and the original strains in simulated small intestinal condition except for Bifidobacterium adolescentis (p<0.05). The presence of 15 ml of supernatants of acid-bile-NaCl-adapted isolates and also those of the initial Bifidobacterium strains inhibited pathogenic bacterial growth for 24 hrs. Probiotic bacteria with improved ability to survive in harsh gastrointestinal environment could be obtained by subsequent treatment of the strains in acid, bile salts and NaCl environments.

Synthesis and antimicrobial effects of silver nanoparticles produced by chemical reduction method.

BACKGROUND AND THE PURPOSE OF THE STUDY: The most prominent nanoparticles for medical uses are nanosilver particles which are famous for their high anti-microbial activity. Silver ion has been known as a metal ion that exhibit anti-mold, anti-microbial and anti-algal properties for a long time. In particular, it is widely used as silver nitrate aqueous solution which has disinfecting and sterilizing actions. The purpose of this study was to evaluate the antimicrobial activity as well as physical properties of the silver nanoparticles prepared by chemical reduction method. METHODS: Silver nanoparticles (NPs) were prepared by reduction of silver nitrate in the presence of a reducing agent and also poly [N-vinylpyrolidone] (PVP) as a stabilizer. Two kinds of NPs were synthesized by ethylene glycol (EG) and glucose as reducing agent. The nanostructure and particle size of silver NPs were confirmed by scanning electron microscopy (SEM) and laser particle analyzer (LPA). The formations of the silver NPs were monitored using ultraviolet- visible spectroscopy. The anti-bacterial activity of silver NPs were assessed by determination of their minimum inhibitory concentrations (MIC) against the Gram positive (Staphylococcus aureus and Staphylococcus epidermidis) as well as Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. RESULTS AND CONCLUSION: The silver nanoparticles were spherical with particle size between 10 to 250 nm. Analysis of the theoretical (Mie light scattering theory) and experimental results showed that the silver NPs in colloidal solution had a diameter of approximately 50 nm. Both colloidal silver NPs showed high anti-bacterial activity against Gram positive and Gram negative bacteria. Glucose nanosilver colloids showed a shorter killing time against most of the tested bacteria which could be due to their nanostructures and uniform size distribution patterns.

Live and heat-inactivated lactobacilli from feces inhibit Salmonella typhi and Escherichia coli adherence to Caco-2 cells.

A quantitative approach has been proposed to evaluate the competitive inhibition of Escherichia coli and Salmonella typhi by live and heat-inactivated laboratory isolated Lactobacillus sp. on adhesion to monolayer of Caco-2 cells. Three species of Lactobacillus (L. casei, L. acidophilus, L. agilis) isolated from human neonate feces and two commercial probiotic strains (L. casei, L. acidophilus) have been compared for probiotic activity. All lactobacilli were able to attach to the Caco-2 cells, however, the degree of adhesion was bacterial strain-dependent. The adhesion indices of the two commercial probiotic strains were not significantly different from the values obtained for the other two similar fecal strains (p > 0.01). The inhibition of attachment of the pathogenic bacteria by inactivated cells of fecal L. acidophilus was examined and compared to the results of live bacteria. The inhibition pattern was similar for live and heat-inactivated L. acidophilus (p > 0.01). The number of attached pathogenic bacteria to the Caco-2 cells decreased when the number of L. acidophilus increased from 10(6) to 10(9) CFU/mL. The heat-inactivated L. acidophilus displayed similar probiotic activity compared to the live bacteria.

Effects of salinity on beta-carotene production by Dunaliella tertiolecta DCCBC26 isolated from the Urmia salt lake, north of Iran.

This study examined the effect of different salt concentrations (0.05-3 M of NaCl) on the kinetics of growth, total carotenoids and beta-carotene (all-trans and 9-cis) accumulated in Dunaliella tertiolecta DCCBC26, a microalgae strain isolated from the Urmia hypersaline lake, northwest of Iran. Results indicated that the highest amount of carotenoids detected (11.73 mg/l) was in the salinity of 0.5 M NaCl during the stationary growth phase. The percentage of the all-trans and 9-cis-beta-carotene in the exponential phase were 92% and 32% in salinities of 3 M and 0.5 M, respectively. However, only 23% of the beta-carotene was detected in the stationary growth phase of the microalgae in 0.5 M salinity and was 9-cis isomer.

Efficiency of an infiltration basin in removing contaminants from urban stormwater.

The efficiency of a Stormwater Infiltration Basin (SIB) to remove contaminants from urban stormwater was assessed in the current investigation. The SIB, installed in an urban suburb in eastern Sydney (Australia), was monitored over seven rainfall events to assess the removal efficiency of the remedial device for total suspended solids (TSS), nutrients (TP, TKN, N(ox), TN), trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn), organochlorine pesticides and faecal coliforms (FC) from stormwater. The weighted average concentration (WAC) of TSS in the stormwater effluent from the SIB was reduced by an average of 50%, whereas the WAC of Cu, Pb and Zn were also reduced by an average 68%, 93% and 52%, respectively. However, the WAC of Cr, Fe, Mn and Ni displays either similar concentrations as the stormwater influent (Cr and Mn), or substantially higher concentrations (Fe and Ni), due possibly to leaching of fine-grained zeolite clay particles in the filtration bed. The mean removal efficiency of the SIB for total phosphorus (TP) and total Kjeldahl nitrogen (TKN) was 51% and 65%, respectively. In contrast, the average WAC of oxidisable nitrogen (nitrate and nitrite nitrogen or N(ox) is about 2.5 times greater in the effluent (1.34 +/- 0.69 mg L(-1)) than in the incoming stormwater (0.62 +/- 0.25 mg L(-1)). The WAC of total nitrogen (TN) was similar for stormwater at the in-flow and out-flow points. The SIB was very efficient in removing FC from stormwater; and the WAC of almost 70000 cfu (100 mL)(-1) at inflow was reduced to <2000 cfu (100 Ml)(-1) at the outflow, representing a mean removal efficiency of 96%. Due to the low concentrations of Cd, organochlorine pesticides and PAHs in the stormwater, it was not possible to assess the efficiency of the SIB in removing these contaminants.

Antimicrobial activity of crude methanolic extract of Satureja khuzistanica.

The methanolic extract of the aerial parts of Satureja khuzistanica was investigated for its antimicrobial activity. The maximum antibacterial and antifungal activities were observed against Staphylococcus aureus and Candida albicans.

Inhibition of nitrofurantoin reduction by menthol leads to enhanced antimicrobial activity.

Nitrofurantoin is a nitroaromatic compound used for the treatment of urinary tract infections. Nitrofurantoin activity is regulated by a nitroreduction process. It is first reduced by bacterial nitroreductases to active short-life intermediates, which are further converted to non-toxic molecules, which negatively affect its antibacterial activity. In this study we have shown that resistant strains of Klebsiella sp. inactivate the bactericidal activity of nitrofurantoin. Also we demonstrated a synergistic effect between menthol and nitrofurantoin bactericidal activities against nitrofurantoin susceptible Enterobacteriaceae.

Group a streptococcal serotypes isolated from healthy schoolchildren in iran.

Serotypes of group A streptococci are still a major cause of pharyngitis and some post-infectious sequelae such as rheumatic fever. As part of the worldwide effort to clarify the epidemiological pattern of group A streptococci in different countries, the present study was conducted to assess the prevalence of Streptococcus pyogenes serotypes in Iran. A total of 1588 throat swabs were taken from healthy school children in the city of Gorgan during February and March 1999. Of those isolates, 175 resulted positive for group A streptococci. The distribution pattern was similar for girls and boys, with 10.8% and 11.2%, respectively. Urban school children showed a higher rate of colonization compared to those in rural areas. Serotyping was performed on 65 of the positive isolates using standard techniques, and only 21 (32%) were M-type isolates. Their profiles fell into four types with M1 predominating, which could reflect the presence of rheumatic fever in the region. However, when isolates were challenged for T-antigen types, nearly all were positive (94%). The pattern of T types was diverse (18 types), with the most common T types being T1 (26%), TB3264 (15%), TB\1-19 & B\25\1-19 (9.2%) and T2 & 2\28 (7.7%). When isolates were tested for opacity factor, only 23 (35%) were positive while 34 (52%) responded to the serum opacity reaction test. Although the number of isolates in this study was not sufficient to make any epidemiological conclusions, the scarcity of serotyping studies in Iran could render these data useful for future attempts to develop a streptococcal vaccine.

Blood flow to the corpus cavernosum penis in the bull and goat buck during penile quiescence.

Bulls and bucks were used to study the blood flow into and out of the corpus cavernosum penis (CCP) during the non-erect state of the penis. When contrast medium was injected into the dorsal artery of the penis in a bull cadaver and into surgically implanted catheters of anesthetized bucks, it flowed into the cavernous spaces of the CCP via the penetrating arteries. When contrast medium was injected directly into the CCP of the bull and buck there was no evidence of vascular exits along the body of the penis. The only venous outlets from the CCP were in the crus penis area. In the non-erect penis the vascular pressure within the CCP was 17.8 mm Hg higher in the bull and 8.3 mm Hg higher in the buck at the glans area than the crus area. During the non-erect state of the penis most of the blood flow to the CCP is from the dorsal artery of the penis via the penetrating arteries. The results showed that the pressure gradient provides the means for flow of blood from the glans area toward the base or crus penis area. This flow prevents platelet aggregation and clot formation and provides nutrition to local tissue during the long periods of non-erection.