Incidence of postoperative complications in patellar fractures related to different methods of osteosynthesis procedures - a retrospective cohort study

BACKGROUND

Patellar fractures have a comparatively low incidence compared to all fracture frequencies of the musculoskeletal system. However, surgical management is crucial to prevent postoperative complications that affect the knee joint. The purpose of the present study was to evaluate the incidence of postoperative complications and onset of postoperative osteoarthritis related to the chosen technique of patellar fracture management.

METHODS

In a retrospective cohort study consecutive managed, isolated patella fractures were reviewed for demographic data, trauma mechanism, patella fracture type, fixation technique and postoperative complications. The results were documented radiographically and clinically and analysed statistically. The reporting followed the STROBE guidelines.

RESULTS

A total of 112 patients were eligible for data evaluation. Surgical management of comminuted patellar fractures with small fragment screws showed significant fewer postoperative complications compared to other fixation techniques (8%, p < 0.043). The incidence of posttraumatic infection was significantly higher following the hybrid fixation technique with cannulated screws and tension wire than following the other analysed techniques (p = 0.024). No postoperative wound infection was observed after screw fixation or locking plate fixation. Symptomatic hardware was most frequently seen after tension-band fixation. Onset of posttraumatic osteoarthritis was most often found after the hybrid fixation technique (55%).

CONCLUSION

Surgical management of patellar fractures remains crucial but fracture fixation using plating systems or small fragment screws is least associated with postoperative complications.

TRIAL REGISTRATION

Trial registration number (DRKS):00027894.

Treatment of Large Cartilage Defects in the Knee by Hydrogel-Based Autologous Chondrocyte Implantation: Two-Year Results of a Prospective, Multicenter, Single-Arm Phase III Trial

OBJECTIVE

To evaluate the clinical outcome of a hydrogel-based autologous chondrocyte implantation (ACI) for large articular cartilage defects in the knee joint.

DESIGN

Prospective, multicenter, single-arm, phase III clinical trial. ACI was performed in 100 patients with focal full-thickness cartilage defects ranging from 4 to 12 cm² in size. The primary outcome measure was the responder rate at 2 years using the Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

Two years after ACI treatment, 93% of patients were KOOS responders having improved by ≥10 points compared with their pre-operative level. The primary endpoint of the study was met and demonstrated that the KOOS response rate is markedly greater than 40% with a lower 95% CI (confidence interval) of 86.1, more than twice the pre-specified no-effect level. KOOS improvement (least squares mean) was 42.0 ± 1.8 points (95% CI between 38.4 and 45.7). Mean changes from baseline were significant in the overall KOOS and in all 5 KOOS subscores from Month 3 (first measurement) to Month 24 (inclusive) (P < 0.0001). The mean MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score after 24 months reached 80.0 points (95% CI: 70.0-90.0 points) and 92.1 points in lesions ≤ 5 cm².

CONCLUSIONS

Overall, hydrogel-based ACI proved to be a valuable treatment option for patients with large cartilage defects in the knee as demonstrated by early, statistically significant, and clinically meaningful improvement up to 2 years follow-up. Parallel to the clinical improvements, MRI analyses suggested increasing maturation, re-organization, and integration of the repair tissue.

TRIAL REGISTRATION

NCT03319797; EudraCT No.: 2016-002817-22.

The tissue-renin-angiotensin-system of the human intervertebral disc

Symptomatic intervertebral disc (IVD) degeneration accounts for significant socioeconomic burden. Recently, the expression of the tissue renin-angiotensin system (tRAS) in rat and bovine IVD was demonstrated. The major effector of tRAS is angiotensin II (AngII), which participates in proinflammatory pathways. The present study investigated the expression of tRAS in human IVDs, and the correlation between tRAS, inflammation and IVD degeneration. Human IVD tissue was collected during spine surgery and distributed according to principal diagnosis. Gene expression of tRAS components, proinflammatory and catabolic markers in the IVD tissue was assessed. Hydroxyproline (OHP) and glycosaminoglycan (GAG) content in the IVD tissue were determined. Tissue distribution of tRAS components was investigated by immunohistochemistry. Gene expression of tRAS components such as angiotensin-converting enzyme (ACE), Ang II receptor type 2 (AGTR2), angiotensinogen (AGT) and cathepsin D (CTSD) was confirmed in human IVDs. IVD samples that expressed tRAS components (n = 21) revealed significantly higher expression levels of interleukin 6 (IL-6), tumour necrosis factor α (TNF-α), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) 4 and 5 compared to tRAS-negative samples (n = 37). Within tRAS-positive samples, AGT, matrix-metalloproteinases 13 and 3, IL-1, IL-6 and IL-8 were more highly expressed in traumatic compared to degenerated IVDs. Total GAG/DNA content of non-tRAS expressing IVD tissue was significantly higher compared to tRAS positive tissue. Immunohistochemistry confirmed the presence of AngII in the human IVD. The present study identified the existence of tRAS in the human IVD and suggested a correlation between tRAS expression, inflammation and ultimately IVD degeneration.

[Primary fracture protheses and reverse shoulder arthroplasty in complex humeral head fractures : An alternative to joint-preserving osteosynthesis?]

BACKGROUND

The surgical management of complex humeral head fractures has adapted dynamically over the course of the last decade. The primary use of reverse shoulder arthroplasty in elderly patients has gained in relevance due to promising short and middle-term results. Long-term results, however, are still pending. The appliance of anatomical hemiarthroplasty, on the other hand, has lost in significance in favour of osteosynthesis and reverse shoulder arthroplasty.

INDICATIONS

This review article follows the question as to under which circumstances primary fracture arthroplasty reflects an alternative or even a preference to joint-preserving osteosynthesis in the treatment of complex proximal humeral fractures. It also specifies spectrums of indications for anatomical hemiarthroplasty and reverse shoulder arthroplasty.

[Prosthesis replacement in periprosthetic humeral fractures]

OBJECTIVE

Stabilization of the humerus with preservation or restoration of the shoulder function.

INDICATIONS

Always in the presence of a loose prosthesis. It may become necessary in conditions of poor bone stock and if osteosynthesis is not possible.

CONTRAINDICATIONS

Noncompliant patients due to alcohol or drugs. Local infections.

SURGICAL TECHNIQUE

The loose implant is removed using an extended anterior deltopectoral approach. After exploration of the fracture and extended soft tissue release, the glenoidal components are implanted with visualization and protection of the axillary nerve. A long stemmed implant is typically needed on the humeral side. It is anchored in the distal fragment over a length of about 6 cm. Soft tissue tension is crucial, especially with reverse shoulder arthroplasty.

POSTOPERATIVE MANAGEMENT

Postoperatively, the affected limb is immobilized for 6 weeks on a 15° shoulder abduction pillow with active assisted movement therapy up to the horizontal plane. This is followed by gradual pain-adapted increases of movement, muscle coordination, and strength.

RESULTS

In 17 patients with periprosthetic fractures of the humerus surgically treated in our institution, 4 underwent revision arthroplasty because of a loose prosthesis. No intra- or postoperative complications were observed. All fractures healed except one.

Generation of recombinant protein shells of Johnson grass chlorotic stripe mosaic virus in tobacco plants and their use as drug carrier

The development and use of virus-like particles (VLPs) is a growing field with a powerful potential in generation of nanoparticles. In the present study we have attempted to generate and use empty shells of Johnson grass chlorotic stripe mosaic virus (JgCSMV, a member of the genus Aureusvirus, family Tombusviridae) as VLP nanoparticles for drug loading. In order to successfully produce recombinant JgCSMV-derived VLPs, we followed an approach based on cloning of the JgCSMV CP gene into pBI121 vector and introduction of the latter into Agrobacterium rhizogenes and transformation of tobacco cells for coat protein expression. Expression in tobacco tissue was demonstrated in transformed hairy roots as a model system. Recombinant VLPs were purified, analyzed by immune assay and visulalized by electron microscopy. Next, we explored the possibility of using JgCSMV-derived VLPs as a nanocontainer for loading the anticancer drug doxorubicin (DOX), taking advantage of the reversible swelling of VLPs in vitro. The results showed that transformed hairy roots produced high levels of the recombinant protein that readily assembled to form empty shells with overall structure similar to native virus particles. In addition, we demonstrated that JgCSMV-VLPs could function as vehicles able to load the chemotherapeutic drug doxorubicin. To our knowledge, this is the first research addressing the question of how this icosahedral virus (JgCSMV) can be used for the production of nanocontainers for biomedical applications.

Dynamics of the population structure and genetic variability within Iranian isolates of grapevine fanleaf virus: evidence for polyphyletic origin

To determine the genetic diversity and population structure of grapevine fanleaf virus (GFLV), the complete nucleotide sequence of the coat protein gene of 41 isolates from different regions in Iran was determined. Phylogenetic analyses of these isolates together with those available in the GenBank revealed two evolutionary divergent lineages, designated GFLV-G and GFLV-Ir that reflect origin of the isolates. Analysis of the genetic variability in the coat protein of these isolates revealed 37 genotype groups in GFLV population. Analyses indicate that GFLV-G and GFLV-Ir clades are significantly differentiated populations of GFLV. Also, geographical subpopulations of the virus in Iran were completely distinct from each other. Examination of nonsynonymous/synonymous nucleotide diversity showed that the CP gene has been under purifying selection. The neutrality tests indicate balancing selection operating within isolates of the northwest of Iran and purifying selection within the other populations.

Biomechanical investigation of a minimally invasive posterior spine stabilization system in comparison to the Universal Spinal System (USS)

Background

Although minimally invasive posterior spine implant systems have been introduced, clinical studies reported on reduced quality of spinal column realignment due to correction loss. The aim of this study was to compare biomechanically two minimally invasive spine stabilization systems versus the Universal Spine Stabilization system (USS).

Methods

Three groups with 5 specimens each and 2 foam bars per specimen were instrumented with USS (Group 1) or a minimally invasive posterior spine stabilization system with either polyaxial (Group 2) or monoaxial (Group 3) screws.

Mechanical testing was performed under quasi-static ramp loading in axial compression and torsion, followed by destructive cyclic loading run under axial compression at constant amplitude and then with progressively increasing amplitude until construct failure.

Bending construct stiffness, torsional stiffness and cycles to failure were investigated.

Results

Initial bending stiffness was highest in Group 3, followed by Group 2 and Group 1, without any significant differences between the groups.

A significant increase in bending stiffness after 20’000 cycles was observed in Group 1 (p = 0.002) and Group 2 (p = 0.001), but not in Group 3, though the secondary bending stiffness showed no significant differences between the groups.

Initial and secondary torsional stiffness was highest in Group 1, followed by Group 3 and Group 2, with significant differences between all groups (p ≤ 0.047). A significant increase in initial torsional stiffness after 20’000 cycles was observed in Group 2 (p = 0.017) and 3 (p = 0.013), but not in Group 1.

The highest number of cycles to failure was detected in Group 1, followed by Group 3 and Group 2. This parameter was significantly different between Group 1 and Group 2 (p = 0.001), between Group 2 and Group 3 (p = 0.002), but not between Group 1 and Group 3.

Conclusions

These findings quantify the correction loss for minimally invasive spine implant systems and imply that unstable spine fractures might benefit from stabilization with conventional implants like the USS.

Anatomical assessment of iliac crest graft size for anterior spondylodesis

Standard procedure for monosegmental anterior spondylodesis often combines anterior stabilization with autologous iliac crest graft. Recent publications defined a minimum size of the graft as a technical specification for this procedure. The cross sectional area of the graft to be transplanted should be at least 23.9% of the cross sectional area of the vertebral bodies to be fused. We investigated whether the required minimum size of autologous graft, as identified both experimentally and clinically, is compatible with the anatomical conditions in central european patients. Computed tomography scans (n = 348) of polytraumatized patients were obtained in the course of initial diagnosis. The scans were evaluated for vertebral body size and the possible size of autologous bone graft in the region of the anterior superior iliac crest. The evaluation of 348 CT scans demonstrated that 95% of the quantified iliac crest grafts would achieve the size recommended for anterior spinal fusion between T10 and T12. In 90% of all cases the planned iliac crest graft exceeded the size limit of 23,9% between concerning the endplates T10 and L2. In 85% the planned iliac crest graft exceeded the size limit of 23,9% between T10 and L3. The recommendation to take this value into account for monosegmental anterior spondylodesis should gain in importance in clinical practice.

Tears of the rotator cuff. Causes--diagnosis--treatment

Rotator cuff ruptures are the most common degenerative tendon injury and occur mainly in older patients as multifactorial disorders manifesting the main symptoms of pain and restricted range of motion. Thorough clinical examination of the shoulder includes testing the function of the rotator cuff and leads to a tentative clinical diagnosis that is the prerequisite for diagnostic imaging procedures. Sonography of the shoulder gives rapid access to a very good sensitive overview of the rotator cuff. Conventional radiological imaging permits differential diagnosis since a reduced acromiohumeral interval is understood as a direct sign of rotator cuff rupture. The gold standard in imaging diagnostics is MRI because it not only delivers images of rotator cuff defects, but also permits interpretation of degenerative changes in the musculature. Significant pain relief can be achieved by conservative therapy such as analgesia, manual therapy and physiotherapeutic exercises and leads to improvements in the active range of motion. Persistent pain or progressive pain during conservative therapy are indications for surgical intervention. Arthroscopy-assisted treatment is tissue friendlier than open surgery and is today considered the standard for surgical treatment of rotator cuff rupture because of higher patient acceptance. Recent studies report that surgical rotator cuff repair leads to significant improvement in function, pain relief, and greater patient satisfaction. The principles of postoperative care after surgical rotator cuff repair are immobilization and gradual loading with passive and active exercises.

[Comparing effectivity of VAC therapy for treatment of infections following arthroplasty or soft-tissue surgery]

BACKGROUND

Although vacuum-assisted wound closure (VAC) has been developed into a standard technique in septic surgery, reliable data about the efficacy of the treatment are still lacking.

PATIENTS

Postoperative infections after arthroplasty or soft-tissue surgery were identified using a prospective database for complications (Critical Incidence Reporting System) which was retrospectively supplemented with items for evaluation of VAC therapy. Eradication success of infection was analysed considering epidemiological parameters, course of treatment, and characteristics of causing bacterial strains. Furthermore, serological C-reactive protein (CRP) concentrations were evaluated for diagnostic and prognostic reliability.

RESULTS

92 patients with an average age of 60 ± 4 years were included in the study. Patients with soft tissue infections (STI, n = 53) were statistically significant younger compared to patients with infections following arthroplasty (AI, n = 39) (53 ± 6 vs. 70 ± 4 years; p < 0.001), but the probability for eradication success was not dependent on age. Mortality was 9-fold higher in the AI group (p < 0.01). Patients with infected endoprostheses were longer treated on intensive care units (6.1 ± 8.4 vs. 3.5 ± 6.5 days; p < 0.01), but there was no statistically significant association to eradication success. Probability for eradication of infection was with 81 % statistically significant higher in the STI group compared to 38 % in the AI group (p < 0.001). Early infections in the AI group were associated with a better healing success when compared to chronic infections (p < 0.05). The same correlation could be shown for the removal of implant (p < 0.0001). Aerobic fermenting bacteria were less effectively eradicated than anaerobic germs following soft-tissue infections (p < 0.01). In cases of osteomyelitis following soft-tissue infection, the probability for eradication of infection was impaired (p < 0.001). Kind and quality of final wound closure in the STI group were statistically significantly associated with eradication success (p < 0.001). There was no critical value concerning the number of revisions until healing of infection was reached. CRP values were higher in the AI group and associated with the prognosis (p < 0.05).

CONCLUSION

Probability of eradication success using VAC therapy is higher after soft-tissue infections compared to infections following arthroplasty. Accordingly, mortality is higher in this group. Chronic courses have worse chances for healing in both groups. For serological CRP values a prognostic relevance could be shown.

Occurrence and Partial Characterization of Lettuce big vein associated virus and Mirafiori lettuce big vein virus in Lettuce in Iran

Mirafiori lettuce big vein virus (MiLBVV) and lettuce big vein associated virus (LBVaV) were found in association with big vein disease of lettuce in Iran. Analysis of part of the coat protein (CP) gene of Iranian isolates of LBVaV showed 97.1-100 % nucleotide sequence identity with other LBVaV isolates. Iranian isolates of MiLBVV belonged to subgroup A and showed 88.6-98.8 % nucleotide sequence identity with other isolates of this virus when amplified by PCR primer pair MiLV VP. The occurrence of both viruses in lettuce crop was associated with the presence of resting spores and zoosporangia of the fungus Olpidium brassicae in lettuce roots under field and greenhouse conditions. Two months after sowing lettuce seed in soil collected from a lettuce field with big vein affected plants, all seedlings were positive for LBVaV and MiLBVV, indicating soil transmission of both viruses.

[Traumatic injuries of the sternoclavicular joint]

Traumatic injuries of the sternoclavicular joint occur rarely and are mainly caused by an indirect trauma mechanism with high kinetic energy. Anterior dislocation is much more common than posterior dislocation, which may be associated with life-threatening injuries. The CT scan is the diagnostic tool of choice for accurate assessment of the injury and coexisting pathologies. The primary goal in anterior and posterior dislocations is an early closed reduction. In cases of redislocation after closed reduction of an anterior dislocation we recommend primary joint reconstruction on the basis of an individual therapeutic concept. Posterior dislocations often cannot be reduced by closed means. Then open reconstruction and stabilization are performed. Chronic instabilities should only be addressed surgically in cases of persistent pain and/or functional deficit. Resection of the medial clavicula represents an effective treatment option in post-traumatic sternoclavicular joint arthritis provided that the costoclavicular ligaments are intact or will be reconstructed during surgery. Physeal injuries of the medial clavicle can occur until an approximate age of 25. Closed reduction of dislocated physeal injuries is attempted. After reposition non-operative treatment in general leads to a good functional outcome. Posteriorly dislocated physeal injuries often cannot be reduced by closed means. In these cases good function can be expected after open stabilization.

Witches'-Broom Disease of Lime Affects Seed Germination and Seedling Growth But Is Not Seed Transmissible

Witches'-broom disease of lime (WBDL), caused by 'Candidatus Phytoplasma aurantifolia', has devastated many Mexican lime orchards and is currently a threat to lime production in neighboring provinces of southern Iran. Several reports have suggested transmission and spread of WBDL phytoplasma through the seed of infected plants. In the present study, claims of seed transmission of this phytoplasma were examined. Fruit were collected from infected trees in the infested areas of Minab (Hormozgan Province) and from symptomless trees in noninfested areas. Lime seed from symptomless and witches'-broom-affected trees were sown in separate beds in an insect-proof screenhouse and the resulting seedlings were examined for phytoplasmal infection. Leaf, stem, and root samples were collected from both groups of seedlings every 3 months for 2 years and tested for WBDL phytoplasma using direct and nested polymerase chain reaction (PCR). Repeated PCR tests on the seedlings did not reveal the presence of phytoplasmal DNA. Likewise, symptoms of the disease were not observed on these seedlings after 2 years. PCR assays detected the phytoplasma in coats of some seed from infected trees; however, no excised embryos were positive for the phytoplasma. All positive PCR results were confirmed by restriction fragment length polymorphism assay. One-year-old seedlings derived from seed of noninfected plants appeared more vigorous in terms of height, number of leaves, and fresh weight of shoot compared with those from infected trees. The germination percentage, mean daily germination, peak value, and germination value were significantly higher for seed of fruit from noninfected trees and seed from fruit on asymptomatic branches of infected trees than those from fruit on symptomatic branches of infected trees.

Fractures of the scapula

The scapula connects the arm with the chest wall and is therefore of great importance for a free range of shoulder of motion. For a long-term scapular fractures had been treated predominantly conservative. However, clinical studies of the past decades revealed that some fracture patterns deserve operative treatment to prevent unfavorable functional outcome and chronic state of pain. Scapular fractures are predominantly acquired during high-energy trauma and these patients' presents with a mean of 3.9 associated injuries in the emergency department. Injuries to the head, chest and ipsilateral upper extremity are most common. As some of these injuries are possibly life threatening they are treated first. Scapular fractures are only very seldom surgical emergencies. Therefore they are treated during the phase of reconvalescence in polytraumatized patients. Decision-making should be based on a thoroughgoing diagnostics, including conventional x-rays and a CT-scan, epically in cases of glenoid neck or cavity fractures. All fracture patterns should be identified to there full extend and put into the context of the scapular suspensory complex. The OTA lately presented a new and comprehensive system for classification of the scapular fractures. It is divided in two levels. Level one for the general orthopedic or trauma surgeon and Level two for the advanced upper Extremity or Shoulder surgeon. This classification scheme allows an easy access to understanding of the severity and prognostics of scapular fractures. As a general guideline surgery is indicated if a double disruption of the Scapula suspensory system, a relevant malposition or dysintegrity of the glenoid (articular surface) or a displacement of the lateral column is present.

Emphysematous pyelonephritis in a transplant kidney

Emphysematous pyelonephritis (EPN) is a severe necrotizing infection of the kidney and its surrounding tissues. It is characterized by the production of gas within the kidney and perinephric structures. EPN often affects diabetic women but can also occur in nondiabetic patients who have ureteral obstruction and in immunocompromised patients. Herein, we report EPN in a 23-year-old woman who had a renal transplantation.

Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder

OBJECTIVE

To define prognostic factors in chronically symptomatic patients with calcific tendinitis of the shoulder.

METHODS

We evaluated 420 patients (488 shoulders) in the context of a prospective cohort study. Epidemiologic data were assessed. The radiographic and sonographic appearance of the calcific deposits was classified. The mean period of nonoperative therapy was 4.4 years (range 0.5-13.7 years). After referral to our institution, standardized nonoperative therapy was continued for a minimum of 3 months. Failure of nonoperative therapy was defined as the persistence of symptomatic calcific tendinitis of the shoulder after a minimum of 6 months. Prognostic factors (determined at P < 0.05 by chi-square test) were analyzed by logistic regression.

RESULTS

Of the 420 patients, 269 (64%) were women, 151 (36%) were men. The mean age of the patients was 51.3 years (range 28-84 years). Occurrence of calcific tendinitis of the shoulder was unilateral in 84% and bilateral in 16%. Gärtner type I calcific deposits were found in 37%, type II in 32%, and type III in 31%. Failure of nonoperative therapy was observed in 114 patients (27%). Negative prognostic factors were bilateral occurrence of calcific tendinitis of the shoulder, localization to the anterior portion of the acromion, medial (subacromial) extension, and high volume of the calcific deposit. Positive prognostic factors were a Gärtner type III deposit and a lack of sonographic sound extinction of the calcific deposit.

CONCLUSION

Our findings demonstrate the existence of prognostic factors in the nonoperative treatment of chronic symptomatic calcific tendinitis of the shoulder. Guidelines for optimal treatment can be implemented according to these factors to avoid a long-term symptomatic disease course.

Molecular characterization of the plant virus genus Ourmiavirus and evidence of inter-kingdom reassortment of viral genome segments as its possible route of origin

Ourmia melon virus (OuMV), Epirus cherry virus (EpCV) and Cassava virus C (CsVC) are three species placed in the genus Ourmiavirus. We cloned and sequenced their RNA genomes. The sizes of the three genomic RNAs of OuMV, the type member of the genus, were 2814, 1064 and 974 nt and each had one open reading frame. RNA1 potentially encoded a 97.5 kDa protein carrying the GDD motif typical of RNA-dependent RNA polymerases (RdRps). The putative RdRps of ourmiaviruses are distantly related to known viral RdRps, with the closest similarity and phylogenetic affinity observed with fungal viruses of the genus Narnaviridae. RNA2 encoded a 31.6 kDa protein which, expressed in bacteria as a His-tag fusion protein and in plants through agroinfiltration, reacted specifically with antibodies made against tubular structures found in the cytoplasm. The ORF2 product is significantly similar to movement proteins of the genus Tombusviridae, and phylogenetic analysis supported this evolutionary relationship. The product of OuMV ORF3 is a 23.8 kDa protein. This protein was also expressed in bacteria and plants, and reacted specifically with antisera against the OuMV coat protein. The sequence of the ORF3 protein showed limited but significant similarity to capsid proteins of several plant and animal viruses, although phylogenetic analysis failed to reveal its most likely origin. Taken together, these results indicate that ourmiaviruses comprise a unique group of plant viruses that might have evolved by reassortment of genomic segments of RNA viruses infecting hosts belonging to different eukaryotic kingdoms, in particular, fungi and plants.

Characterisation of lettuce virus X, a new potexvirus infecting lettuce in Iran

A virus with flexuous rod-shaped particle morphology was found in samples from lettuce during a survey of viruses infecting lettuce in Tehran province in Iran. This virus was subjected to a complete analysis of its biological and molecular features. The entire nucleotide sequence of the virus was determined, revealing a polyadenylated ssRNA genome consisting of 7,212 nucleotides [without poly (A) tail] and possessing an organization typical for potexviruses. Comparative genome analysis showed that the lettuce virus is closely related to Alstroemeria virus X, narcissus mosaic virus and asparagus virus 3. Based on particle morphology, physico-chemical properties and the complete genome sequence, this virus is a member of a new species in the genus Potexvirus, for which the name lettuce virus X (LeVX) is proposed. Biological assays using an infectious cDNA clone and a wild-type isolate of LeVX revealed that the virus, despite reaching high concentrations in all lettuce cultivars tested, does not cause symptoms in lettuce.

Analysis of nucleotide sequence of Iranian maize mosaic virus confirms its identity as a distinct nucleorhabdovirus

The nucleotide sequence of the Iranian maize mosaic rhabdovirus (IMMV) was obtained using a random-PCR method (rPCR) followed by PCR with specific primers. Analysis of the complete nucleotide sequence of the IMMV genes and intergenic regions comprising a total of 12,381 nucleotides (including the partial sequences of leader and trailer regions) revealed six open reading frames (ORF) on the viral complementary RNA (vcRNA). On the basis of its similarities to other rhabdovirus sequences, the IMMV genome consists of 3'-leader-N-P-3-M-G-L-5'-trailer. The intergenic regions contained a characteristic consensus sequence, 3'-AAUUCUUUUUGGGUUU/G-5'. The IMMV gene products showed a high similarity to those of maize mosaic virus and taro vein chlorosis virus and a more distant relationship to other rhabdoviruses. Together with the biological, serological and morphological features described earlier, our molecular data provide evidence that IMMV is a distinct member of the genus Nucleorhabdovirus in the family Rhabdoviridae.

First Report of 'Candidatus Phytoplasma trifolii'-Related Strain Associated with Safflower Phyllody Disease in Iran

During a survey in 2003, safflower plants (Carthamus tinctorius) with phyllody symptoms were observed in production fields in several districts of Fars and Yazd provinces in Iran. Affected plants showed floral virescence, phyllody, proliferation of axillary buds, and little leaf symptoms. Incidence of the disease was less than 10%. Direct and nested PCR assays were used to verify association of phytoplasma with the disease. Total DNA was extracted from fresh, fine roots of eight phyllody-affected safflower plants and one symptomless plant. With phytoplasma universal primer pair P1/P7 (5'-AAGAGTTTGATCCTGGCTCAGGATT-3'/5'-CGTCCTTCATCGGCTCTT-3'), target DNA fragments of approximately 1.8 kb were amplified by direct PCR from phyllody-affected plants and Iranian cabbage yellows (ICY) phytoplasma used as a positive control. Reamplification of P1/P7 products with 16S rRNA gene primer pair R16F2n/R16R2 (5'-GAAACGACTGCTAAGACTGG-3'/5'-TGACGGGCGGTGTGTACAAACCCCG-3') yielded fragments of the expected size (1.2 kb) from all eight diseased plants and the ICY-positive control. No products were amplified from the symptomless plant by either assay. R16F2n/R16R2 products were subjected to restriction fragment length polymorphism (RFLP) analysis by separate digestion with AluI, HaeIII, HhaI, HinfI, HpaII, MseI, RsaI, Sau3AI, or TaqI endonuclease. Comparison of resulting RFLP patterns with published patterns of other phytoplasmas (2) tentatively identified safflower phyllody (SP) phytoplasma as a member of clover proliferation group 16SrVI, subgroup C. HhaI digests also differentiated SP from ICY phytoplasma, a previously reported subgroup 16SrVI-A strain (3). After sequencing of the 16S rDNA fragment (GenBank Accession No. DQ88948), a BLAST search determined that SP phytoplasma shared closest homology with 16SrVI group members ('Candidatus Phytoplasma trifolii') and related strains (4). Furthermore, phylogenetic analysis of 16S rDNA sequences revealed SP phytoplasma to be most similar (99.7%) to brinjal little leaf (BLL) phytoplasma (GenBank Accession No. X83431). Analysis of putative restriction sites in 16S rRNA gene sequences revealed that SP and BLL shared identical restriction profiles and that both differed from the 'Ca. Phytoplasma trifolii' reference strain (GenBank Accession No. AY390261) because of the absence of a single HhaI site and the presence of an additional MseI site. Although safflower phyllody disease has been previously reported in Israel, the associated phytoplasma was classified as a strain of the aster yellows subgroup 16SrI-B (1). To our knowledge, this is the first report of safflower as a host of a 'Ca. Phytoplasma trifolii'-related strain. References: (1) M. Klein. Plant Dis. Rep. 54:735, 1970. (2) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:1037, 2004. (3) M. Salehi et al. Plant Dis. 91:625, 2007. (4) K. Wang and C. Hiruki, Phytopathology 91:546, 2001.

Characterization of a Phytoplasma Associated with Cabbage Yellows in Iran

In 2001, a disease tentatively named Iranian cabbage yellows (ICY) was observed in cabbage fields of Zarghan (Fars Province, Iran). The major symptoms of the disease were yellowing, little leaves, plant stunting, opening of the head, and proliferation of the buds at the base of the stem into a witches'-broom. Among leafhoppers collected in cabbage fields, only Circulifer haematoceps transmitted the ICY agent. The disease agent was transmitted by the leafhopper from cabbage to cabbage, cauliflower, rape, and periwinkle, causing phytoplasma-type symptoms in these plants. Polymerase chain reaction (PCR) using phytoplasma-specific primer pair P1/P7 and nested PCR using P1/P7 and R16F2n/R16R2 primer pairs amplified products of expected size (1.8 and 1.2 kb, respectively) from symptomatic cabbage plants. Both restriction fragment length polymorphism (RFLP) of nested PCR products (1.2 kb) and phylogenetic analyses of 16S-23S rDNA spacer region sequence indicated that the ICY phytoplasma had the closest relationship to subgroup A members of the clover proliferation group, including beet leafhopper-transmitted virescence agent, 'Candidatus Phytoplasma trifolii', Columbia Basin potato purple top phytoplasma, and vinca virescence phytoplasma. Cabbage is reported as a new natural host to the 16SrVI group of phytoplasmas.

Transmission of 'Candidatus Phytoplasma aurantifolia' to Bakraee (Citrus reticulata Hybrid) by Feral Hishimonus phycitis Leafhoppers in Iran

Witches'-broom disease of lime (WBDL) caused by 'Candidatus Phytoplasma aurantifolia' is a devastating disease in the Sultanate of Oman, United Arab Emirates, and southern Iran. The disease primarily affects lime (Citrus aurantifolia), but in Iran, it is also found in bakraee, a natural C. reticulata hybrid. The disease has been experimentally transmitted from lime to several citrus cultivars by grafting and to a number of herbaceous hosts by dodder. However, the natural vector of 'Ca. P. aurantifolia' has not been determined. The most common phloem-feeding insect associated with lime trees in the area is the leafhopper Hishimonus phycitis. The WBDL phytoplasma has been detected in the body of this leafhopper by ELISA and PCR (1), but previous attempts to establish its vector status have failed. It was recently reported that the leafhopper can release the phytoplasma into a sugar solution by feeding through a Parafilm membrane (4). Here we report successful transmission of WBDL phytoplasma to bakraee seedlings by H. phycitis. The leafhopper nymphs and adults were collected in a WBDL-infected lime orchard in Minab (Hormozgan Province) in May of 2006. Of more than 100 leafhopper samples tested, at least 70% were positive for the phytoplasma by PCR using P1/P7 primer pair (3). Additional field-collected leafhoppers were caged (five per plant) on bakraee seedlings at the two-leaf stage in pots in the greenhouse in Zarghan (Fars Province). After 8 weeks, the remaining leafhoppers were killed with an insecticide. Six months after inoculation, 3 of 10 inoculated plants showed typical symptoms of WBDL, including bud proliferation, general chlorosis, and stunting. Symptomatic plants were strongly positive in PCR assays using primer pair P1/P7. No amplification was obtained with healthy control lime or nonsymptomatic bakraee seedlings. Amplified P1/P7 primed PCR products (1,800 bp) from experimentally vector-challenged bakraee seedlings, captured H. phycitis, and a naturally infected lime tree from Minab were subjected to restriction fragment length polymorphism (RFLP) analysis using AluI, HhaI, HpaII, RsaI, and TaqI enzymes. RFLP patterns from these sources were identical and similar to those reported earlier (2). These analyses verified the identity of WBDL phytoplasma in experimentally infected bakraee seedlings. To our knowledge, this is the first report of natural transmission of 'Ca. P. aurantifolia' by H. phycitis. References: (1) J. M. Bové et al. Proc. Conf. IOCV 12:342. 1993. (2) A. J. Khan et al. Phytopathology 92:1038, 2002. (3) B. Schneider et al. Pages 369-380 in: Molecular and Diagnostic Procedures in Mycoplasmology. Vol. 2. S. Razin and J. G. Tully, eds. Academic Press, New York, 1995. (4) M. Siampour et al. Iran. J. Plant Pathol. 41:139 (Farsi) and 35 (English), 2006.

A New Phytoplasma Infecting Lettuce in Iran

Lettuce phyllody (LP) is an economically important disease of romaine lettuce (Lactuca sativa) in vegetative crop and seed crop fields in the Fars Province of Iran. Wild lettuce phyllody (WLP) occurs also in epidemic proportions in wild lettuce (L. serriola) during the fall in Iranian central and southern provinces, especially in Fars. Among various leafhopper species tested, Neoaliturus fenestratus successfully transmitted agents of LP and WLP to lettuce, wild lettuce, periwinkle, and sowthistle directly after field collection or after 5 to 7 days of feeding on diseased source plants. With primer pair P1/P7 in polymerase chain reaction (PCR), target DNA fragments (1.8 kbp) were amplified from total nucleic acid samples extracted from diseased lettuce and wild lettuce plants, but not from healthy counterparts. On the basis of disease symptoms, leafhopper transmission, and positive reaction in phytoplasma-specific PCR, Iranian lettuce and wild lettuce phyllodies agents have phytoplasmal etiology. Phylogenetic and putative restriction site analysis of 16S/23S rDNA spacer region (SR) indicated that LP and WLP phytoplasmas are members of pigeon pea witches'-broom (16SrIX) group and are closely related. Reciprocal transmission of LP phytoplasma to wild lettuce and WLP phytoplasma to lettuce by the same leafhopper species and induction of similar symptoms in common hosts are other evidences that agents of LP and WLP may be related or identical phytoplasmas. This is the first report of lettuce as a new host in pigeon pea witches'-broom group and N. fenestratus as a vector of a pigeon pea witches'-broom group phytoplasma. In other countries, phytoplasmas of aster yellows group (16SrI) are commonly associated with phytoplasmal lettuce diseases (2) and Macrosteles quadrilineatus leafhopper is reported as the vector (1). Relatedness of WLP phytoplasma to 16SrIX group was previously reported (3). On the basis of the results of this study, wild lettuce and sowthistle are two reservoirs of LP phytoplasma. References: (1) D. Errampalli et al. Phytopathology 76:1084, 1986. (2) I.-M. Lee et al. Ann. Rev. Microbiol. 54:221, 2000. (3) E. Verdin et al. Int. J. Syst. Bacteriol. Evol. Microbiol. 53:833, 2003.

Determination of seed-born percentages of bean common mosaic necrosis virus (BCMNV) in three genotypes of Phaseolus vulgaris

Bean common mosaic necrosis virus (BCMNV) is one of the most damaging viruses of bean that naturally transmitted by aphid in non persistent manner and through the seeds. BCMNV belongs to the genus Potyvirus and the family Potyviridae. During the growing season of 2004, bean leaf samples with viral symptoms were collected from Tehran province, Karaj region. DAS-ELISA by using BCMNV polyclonal antiserum (AS-0239, prepared in DSMZ, Germany) was conducted and samples with viral infection were distinguished. IC-RT-PCR was done to amplify the cp gene of isolates. The nucleotide sequence of one isolate was determined and analysis of this and other published sequences confirmed this isolate as BCMNV. The confirmed isolate was inoculated on three bean genotypes (butter bean ks-21478, kidney bean ks-31170, navy bean ks-41235) using 0.01 M Potassium phosphate buffer (pH = 7). After appearance of symptoms, the inoculated plants were tested by DAS-ELISA and IC-RT-PCR. In DAS-ELISA test, 68% infection of butter bean and kidney bean genotypes and only 7% infection of navy bean genotype were confirmed. In IC-RT-PCR by using specific primers (NL3), a 922 bp fragment was amplified in all genotypes, even symptomless plants and the ones which were negative in ELISA test. To determine the percentages of infected seed, harvested seeds were planted. Most of the seedlings in two-leaf stage died with black root symptoms. All seedlings were tested by DAS-ELISA and IC-RT-PCR. The results of these assays showed that the percentage of seed infected was 78%.

Comparison of biological and molecular characterization of Iranian lettuce mosaic virus isolates

Lettuce mosaic virus (LMV) is one of the most damaging viruses in lettuce and endive cultivating regions. In order to review the characteristics of different LMV isolates of Iran during 2004-2005 samples were collected from lettuce fields in Esfahan, Ghom, Khorasan, Khuzestan and Tehran provinces. All of the isolates were detected by LMV polyclonal antiserum (AS-0155, DSMZ Germany) in ELISA and TIPA tests. Biological purification was done for the LMV isolates and then they were maintained and propagated on Chenopodium quinoa. A range of plant species such as C. amaranticolor, C. album, Carthamus tinctorius, Gazania sp., Gomphrena globosa, Pisum sativum, Spinacia oleracea were inoculated with these isolates using potassium phosphate buffer (0/05M). Molecular weight of coat protein was determined by Polyacrylamid gel electrophoresis (PAGE). Immunocapture reverse transcription polymerase chain reaction (IC-RT-PCR) was performed using LMV polyclonal antiserum and specific primer pairs of LMV as described by Zerbini et al. (1995). The amplified fragments were included the whole CP and 3'UTR regions and the nucleotide sequences of them determined. All isolates induced chlorotic local lesions on C. amaranticolor and chlorotic local lesions with symptoms of systemic infection (vein clearing) on C. album. Tehran isolate in addition, caused local lesions on Gomphrena globosa with red border and white centre. This isolate infected Pisum sativum without any symptoms. Back inoculation on C. quinoa and DAS-ELISA confirmed the latent infection. None of these isolates infected Carthamus tinctorius, Gazania sp. and Spinacia oleracea. The molecular weight of coat protein was determined 30.33 kDa. Western-blot proved this band as the coat protein of the virus. IC-RT-PCR amplification of LMV isolates produced the expected size IC-RT-PCR product of 1300 bps. The comparison of nucleotide sequences showed that there were 98% identities.

Molecular characterization of Iranian wheat stripe virus shows its taxonomic position as a distinct species in the genus Tenuivirus

The full lengths of three genome segments of Iranian wheat stripe virus (IWSV) were amplified by reverse transcription (RT) followed by polymerase chain reaction (PCR) using a primer complementary to tenuivirus conserved terminal sequences. The segments were sequenced and found to comprise 3469, 2337, and 1831 nt, respectively. The gene organization of these segments is similar to that of other known tenuiviruses, each displaying an ambisense coding strategy. IWSV segments, however, are different from those of other viruses with respect to the number of nucleotides and deduced amino acid sequence for each ORF. Depending on the segment, the first 16-22 nt at the 5' end and the first 16 nt at the 3' end are highly conserved among IWSV and rice hoja blanca virus (RHBV), rice stripe virus (RSV) and maize stripe virus (MStV). In addition, the first 15-18 nt at the 5' end are complementary to the first 16-18 nt at the 3' end. Phylogenetic analyses showed close similarity and a common ancestor for IWSV, RHBV, and Echinochloa hoja blanca virus (EHBV). These findings confirm the position of IWSV as a distinct species in the genus Tenuivirus.

Sporadische zerebrale Amyloidangiopathie mit ischämischer Leukenzephalopathie und Mikroblutungen

We describe a 72-year-old patient with rapidly progressive dementia and a complex focal seizure. Magnetic resonance (MR) imaging revealed leukoencephalopathy with the involvement of the U-fibers as well as cortical and subcortical microbleeds. Brain biopsy confirmed the diagnosis of cerebral Abeta amyloid angiopathy (CAA). The presented case illustrates the significance of CAA as a cause of rapidly progressive dementia and leukoencephalopathy and points out the importance of T2-weighted MR imaging in the evaluation of dementia.

Bermuda Grass as a Potential Reservoir Host for Grapevine fanleaf virus

Grapevine fanleaf virus (GFLV) was detected in samples of Bermuda grass (BG) from Iran by reverse transcription-polymerase chain reaction (RT-PCR) using two different pairs of GFLV-specific primers, and also by enzyme-linked immunosorbent assay (ELISA) using antiserum specific for a North American isolate of the virus. RT-PCR detected GFLV in both fresh and dried BG tissues and in virus preparations purified from these plants. Cloning and sequencing of the RT-PCR products confirmed that the amplified sequences were sections of the GFLV coat protein gene. Similar results were obtained when random and oligo(dT) primers were used on viral RNA templates recovered from BG to synthesize cDNA for cloning and sequencing. The virus induced few or no symptoms in BG, but could nonetheless be transmitted from BG to Chenopodium quinoa by mechanical inoculation. Some isolates induced systemic chlorotic spots and leaf deformation; others remained symptomless in this plant. Both symptomatic and symptomless C. quinoa plants were found to be infected with GFLV, giving positive ELISA and RT-PCR tests. A North American isolate of GFLV was found to be mechanically transmissible to BG as indicated by positive RT-PCR results from root samples of inoculated plants. GFLV-infected BG was widely distributed in the Fars province of Iran.