Interaction between Meloidogyne incognita and Rhizoctonia solani on green beans.

The interaction between Meloidogyne incognita (race 2) and Rhizoctonia solani (AG 4) in a root rot disease complex of green beans (Phaseolus vulgaris) was examined in a greenhouse pot experiment. Three week-old seedlings (cv. Contender) were inoculated with the nematode and/or the fungus in different combinations and sequences. Two months after last nematode inoculation, the test was terminated and data were recorded. The synchronized inoculation by both pathogens (N + F) increased the index of Rhizoctonia root rot and the number of root galls; and suppressed plant growth, compared to controls. However, the severity of root rot and suppression of plant growth were greater and more evident when inoculation by the nematode preceded the fungus (N â†’ F) by two weeks. Nematode reproduction (eggs/g root) was adversely affected by the presence of the fungus except by the synchronized inoculation. When inoculation by nematode preceded the fungus, plant growth was severely suppressed and roots were highly damaged and rotted leading to a decrease of root galls and eggs.

Knowledge, attitudes and practice of dentists concerning the occupational risks of hepatitis B virus in Al Jouf Province, Saudi Arabia.

INTRODUCTION: Hepatitis B virus (HBV) is a well-recognized occupational risk for all health care workers (HCWs) worldwide. In Saudi Arabia, very little is known about knowledge, attitudes, and practice of dentists toward occupational risk of HBV. Our study was conducted to assess the same parameters. METHODS: During February 2012, a cross-sectional survey of 48 dentists with mean age 38 ± 11.2 years was carried out at the primary health care centers in Al Jouf Province of Saudi Arabia. The dentists were asked to fill a valid questionnaire containing their socio-demographic data, and well-designed questions about their knowledge base, attitudes and practice toward occupational risk of HBV. The data were processed and analyzed using the SPSS (version 17) (IBM SPSS Inc., Chicago, IL, USA) program and the level of significance were set at P < 0.05. RESULTS: Response rate of 85.4% yielded 41 questionnaires for analysis. Majority of the dentists surveyed 34 (82.9%) perceived that they are at high risk of contracting and spreading HBV, and 28 (68.3%) had a concern to get HBV. More than half 23 (56.1%) were willing to achieve continuity of care for HBsAg-positive patients. The vast majority 39 (95.1%) believed that HBV vaccine is safe, and 34 (82.9%) were vaccinated. Less than half 17 (41.5%) recognized that HBV is resistant to alcohol and some detergents. During surgical procedures, only 14 (34.1%) always use double gloves and 19 (46.3%) always use goggles. Almost all dentists surveyed were willing to subscribe in a regular training programs about HBV. CONCLUSION: More education focusing on occupational risk of HBV is recommended for dentists.

Correlation between surgical success rate and severity of congenital glaucoma.

AIM: To study the correlation between severity of primary congenital glaucoma (PCG) and success of three types of surgery. METHODS: This was a retrospective review of all records of patients diagnosed with PCG up to age 1 year who underwent goniotomy, trabeculotomy, or combined trabeculotomy-trabeculectomy with mitomycin C as initial procedure between 1982 and 2002 at the King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. 532 paediatric glaucoma patients below age 1 year (820 eyes) with a minimum 1 year follow up were identified. The main outcome measures used for the surgeries were postoperative intraocular pressure, stability of the corneal diameter, and maintenance of corneal clarity. Surgical success was defined as a postoperative intraocular pressure of < or = 21 mm Hg without additional medical or surgical therapy, and with decreased corneal oedema, stabilised corneal diameter, and no additional optic nerve damage for at least 1 year after surgery. Complications, time of surgical failure, and follow up were recorded. RESULTS: The eyes were grouped into mild (249), moderate (342), and severe (229) PCG, based on intraocular pressure, corneal diameter, and clarity. All three surgical procedures resulted in high success rates of 81-100% for the mild form of PCG. Eyes classified with moderate glaucoma had a 13%, 40%, and 80% success rate respectively for goniotomy, trabeculotomy, and combined trabeculotomy-trabeculectomy with mitomycin C. The success rate for severe PCG was 10% and 70% for trabeculotomy and combined surgery respectively. Goniotomy was never done for eyes with this condition. CONCLUSION: Clinical classification of PCG is helpful for surgical decision making. The mild form has a high surgical success regardless of the procedure chosen. Combined trabeculotomy-trabeculectomy with mitomycin C gave the best results for moderate and severe cases of PCG.

Recognized globe perforation during strabismus surgery: incidence, risk factors, and sequelae.

BACKGROUND: Inadvertent perforation of the globe is a well-recognized complication of extraocular muscle surgery. We evaluated the incidence, risk factors, and sequelae of this complication at our institution. METHODS: Medical records of patients who underwent extraocular muscle surgery at King Khaled Eye Specialist Hospital, Saudi Arabia, between September 1983 and April 1997, were reviewed for the occurrence of globe perforation. We documented preoperative visual acuity and refraction, surgical procedure, how the perforation occurred, and immediate management, as well as the sequelae of the perforation, its management, and final outcome. RESULTS: Recognized perforations occurred in 15 of 4886 procedures, for an overall incidence rate of 3/1000. Perforations were 3 times more common in myopic eyes (>-6.00 D, P =.05) and 2 times more common in eyes with previous extraocular muscle surgery. Perforations occurred during muscle reattachment (5 cases), placement of traction sutures at the limbus (4 cases with transient hyphema), muscle disinsertion (3 cases), and placement of sutures at the muscle insertion before disinsertion (3 cases). One patient had a large scleral laceration with uveal prolapse, necessitating scleral patch graft at the time of surgery, and later had retinal detachment surgery with loss of 2 lines of visual acuity. Endophthalmitis, cataract, glaucoma, and phthisis bulbi were not encountered in our review. CONCLUSION: The current incidence of globe perforation is low and only rarely associated with serious sequelae.

Damage and Reproduction Potentials of Heterodera avenae on Wheat under Outdoor Conditions.

TWO POT EXPERIMENTS, IN CONSECUTIVE YEARS, WERE CONDUCTED UNDER OUTDOOR CONDITIONS DURING THE WHEAT GROWING SEASON TO EXAMINE THE RELATIONSHIP BETWEEN INCREASING INITIAL POPULATION DENSITIES (PI: 0-3,000 cysts/pot) of Heterodera avenae and corresponding responses of wheat cv. Yecora Rojo. Results of both experiments were very similar. The nematode suppressed plant height, root and biomass dry weights, and grain yield at all Pi's studied. The suppression of these parameters, as well as the final nematode population densities (Pf), increased with increasing Pi levels. The reproduction factor (Pf/Pi) decreased as Pi increased but was always greater than 1.0. When data from both experiments were combined for regression analyses, inverse relationships were found between log(10) (Pi + 1) and both plant growth and yield. These negative relationships were highly significant and adequately described by linear models. Final population (Pf) increased linearly with Pi. The wheat cultivar cv. Yecora Rojo was found to be highly vulnerable to damage and a good host for H. avenae.

Effectiveness and complications of mitomycin C use during pediatric glaucoma surgery.

PURPOSE: To examine the safety of mitomycin C (MMC) use in pediatric glaucoma surgery. DESIGN: Retrospective interventional case series. PARTICIPANTS: One hundred eighty pediatric glaucoma patients younger than 7 years of age (254 eyes) who underwent glaucoma surgery and were followed for at least 1 year participated. INTERVENTIONS: Surgeries consisted of trabeculectomy or combined trabeculotomy-trabeculectomy with adjunctive use of MMC. MAIN OUTCOME MEASURES: Control of intraocular pressure (IOP) and occurrence of complications were measured. An IOP below 21 mmHg without any additional medical or surgical treatment was considered a success. RESULTS: Primary congenital glaucoma was present in 98% of the patients. Sixty percent had a trabeculectomy, and 40% had a trabeculotomy-trabeculectomy. The combined surgery was performed mostly in infants up to 1 year of age. Complications were cystic bleb (19), bleb leak (4), retinal detachment (3), flat anterior chamber (3), cataract (2), and endophthalmitis (1). Children younger than 2 years of age had fewer complications but higher failure rates. The combined procedure in infants up to 2 years of age was moderately more successful (57%) than trabeculectomy alone (39%). Minimal complications seen in this group were more likely related to young age than to the type of surgery. Complications increased with time after surgery, with most occurring 2 years or more after surgery. CONCLUSIONS: Success of MMC-augmented glaucoma filtering surgery increased with age, as did the complication rate. Serious complications were uncommon in the authors' group of pediatric patients up to now. However, complications related to bleb thinning increased with time after surgery, and additional problems can be anticipated with longer follow-up.

Temporal crescent syndrome with magnetic resonance correlation.

BACKGROUND: A young woman with a history of controlled hypertension noted a suddenly decreased peripheral temporal field in the left eye. This occurred after moderate peripartum hypertension. METHOD: A monocular peripheral temporal crescentic defect could be plotted on Goldmann visual fields despite a normal dilated peripheral retinal examination and normal disc appearance. RESULT: A dilated parieto-occipital sulcus could be seen on computed tomography, and magnetic resonance imaging showed changes consistent with atrophy and gliosis in the cuneus, precuneus, and anterior calcarine cortex surrounding the parieto-occipital sulcus. CONCLUSION: By magnetic resonance imaging, this can be seen to comprise less than 10% of the visual cortex, as suggested by the Horton and Hoyt revised Holmes map. The temporal crescent syndrome is a rare monocular retrochiasmatic visual field defect that can be correlated to a lesion along the parieto-occipital sulcus.

Population Dynamics of Meloidogyne incognita on Corn Grown in Soil in Fested with Arthrobotrys conoides.

Microplot and greenhouse experiments were conducted to evaluate the effects of soil incorporation of the nematophagous fungus Arthrobotrys conoides and green alfalfa mulch on the population dynamics of Meloidogyne incognita on corn. Reproduction of M. incognita and the incidence of root galling were reduced by the addition of A. conoides and/or green alfalfa in all tests. Numbers of juveniles were reduced by as much as 84%, and eggs were fewest in early to mid-season soil samples from microplots. Yields increased in treatments with A. conoides and/or green alfalfa in greenhouse tests and in the microplot tests in 1979. No interaction was found between the fungus and green alfalfa in the reduction of the nematode population.

Biology of Meloidogyne platani Hirschmann Parasitic on Sycamore, Platanus occidentalis.

The development of Meloidogyne platani on sycamore was followed for 40 days (22-28 C). Juveniles penetrated the feeder roots behind the root cap and invaded the vascular cylinder within 3 days after inoculation. All subsequent development of the nematodes and host effects occurred only within the stele. The second juvenile molt and sex differentiation occurred by the 17th day. Young females were observed by the 26th day. Eggs were observed inside the roots by the 35th day and were exposed to the surface of galls by the 40th day. In pathogenicity studies, a significant negative correlation was shown to exist between fresh shoot and root weights and inoculum density. Besides sycamore, white ash was the only hardwood species tested to become infected. Of the herbacious plants tested, tobacco was heavily galled, tomato and watermelon moderately galled, and pepper only slightly galled. Egg production was moderate on tobacco, slight on tomato and watermelon, and absent on pepper.

The Effect of Arthrobotrys conoides on Meloidogyne incognita Population Densities in Corn as Influenced by Temperature, Fungus Inoculum Density, and Time of Fungus Introduction in the Soil.

In greenhouse experiments, the effect of Arthrobotrys conoides on Meloidogyne incognita population densities as affected by soil temperature, inoculum density, and green alfalfa was determined. The effect on M. incognita population densities was greater at a soil temperature of 25 C than at 18 or 32 C. Nematode control by A. conoides was most effective when the fungus was introduced into the soil 2 wk prior to nematode inoculation and planting of corn. Inoculum density of A. conoides was positively correlated with plant shoot weight (r = 0.81) and negatively correlated with numbers of Meloidogyne juveniles (r = -0.96), eggs (-0.89) and galls per gram of root (-0.91). A. conoides was not isolated from green alfalfa, but was isolated from alfalfa-amended soil to which no fungus had been added.