Calcaneal fracture with a concomitant unstable subtalar dislocation: A case report.

BACKGROUND: Traumatic dislocation of the subtalar joint is an infrequently occurring injury, first described by DuFaurest in 1811. They were later on classified by Broca as medial, lateral, posterior and anterior dislocations based on the direction of the dislocation. CASE REPORT: We present a case of a 30 year old male who presented after a 5 m height fall and direct right foot trauma. Investigations done in the emergency department revealed a right subtalar lateral dislocation with associated calcaneal intraarticular displaced fracture. Open reduction internal fixation of the calcaneal fracture was decided alongside with reduction of the subtalar joint. Intraoperatively the subtalar reduction was totally unstable due to the deficiency of the lateral collateral ligament. A decision of reconstruction of the calcaneofibular ligament using a synthetic ligament was taken. This reconstruction resulted in an adequate intraoperative stability of the subtalar joint. On a 2 year follow up the patient was asymptomatic with no residual subtalar instability. DISCUSSION: These injuries must be suspected after high energy trauma or twisting forces in the foot. They occur more frequently in men than in women and predominately affect people in their mid-30 s. Our case is unique in that the reconstruction of the calcaneofibular ligament was done using a synthetic graft to stabilize an acute unstable subtalar joint dislocation. CONCLUSION: Subtalar dislocation is a rare injury with post reduction instability being even rarer. Care has to be taken not to overlook the frequently associated bony injuries, due to their impact on treatment decision and prognosis.

First Report of a γ 3-Proteobacterium Associated with Diseased Strawberries in Italy.

During the fall seasons of 2005 and 2006, diseased strawberry plants (Fragaria × ananassa Duch.) were observed in nurseries and production fields in Ferrara, Forli-Cesena, and Ravenna provinces (Emilia-Romagna region, northern Italy). Symptoms consisted of a conspicuous plant stunting with a poor root system. Older leaves rolled upward and displayed a marked premature purplish discoloration, while young leaves were cupped, chlorotic, generally reduced in size, and had shortened petioles. This strawberry disorder was similar to "marginal chlorosis", an infectious disease occurring in France that can be induced by two different phloem-limited uncultured bacteria: the γ 3-proteobacterium 'Candidatus Phlomobacter fragariae' and the stolbur phytoplasma (16SrXII-A). In strawberry production fields, 'Ca. P. fragariae' is reported as being the prevalent agent of this disease (1). Sixty-seven diseased plants were collected from production fields and nurseries for testing for 'Ca. P. fragariae'. Leaf samples were analyzed by 4',6-diamidine-2-phenylindole staining and PCR. Forty samples showed fluorescent DNA in the phloem, whereas no fluorescence was observed in symptomless strawberries. When tested by PCR with primers Fra4/Fra5, which amplify a 550-bp fragment of the 16S rDNA region of 'Ca. P. fragariae' (1), 13 of 36 strawberries from production fields and 1 of 31 nursery plants gave a positive reaction. On the other hand, 21 samples from nurseries and 5 from production fields tested positive for stolbur phytoplasma (3). No amplification was obtained with DNA from symptomless or healthy strawberry plants. Sequencing Fra4/Fra5 amplicons from three samples (GenBank Accession Nos. DQ362916-DQ362918) showed a 98.1 to 98.6% and a 98.3 to 98.8% identity with the published sequences of the French isolate "LG2001" (GenBank Accession No. AM110766) and the Japanese isolate J-B (GenBank Accession No. AB246669) of 'Ca. P. fragariae', respectively. Higher homology (99.2 to 99.8%) was found with another bacterium-like organism (BLO) of the γ 3-proteobacteria subgroup (GenBank Accession No. AY057392) associated with the syndrome "basses richesses" of sugar beet (SBR). Furthermore, PCR assays performed with primers Pfr1/Pfr4, specific for spoT gene of 'Ca. P. fragariae', did not show any amplification with DNA from the 14 diseased strawberry plants tested. This is in agreement with the SBR BLO identification (2). To better characterize the Italian isolates, the full-length 16S rDNA gene was analyzed with primers fd1/Fra4 and Fra5/rp1, which amplify the 5' and 3' region of 16S rDNA gene of the proteobacteria, respectively (2). PCR products from eight isolates were sequenced, and the 16S rDNA sequences obtained (GenBank Accession Nos. DQ538372-DQ538379) showed a 96.4 to 97.3% identity with the known 'Ca. P. fragariae' isolates, while a higher homology (99.4 to 99.9%) was again found with the SBR BLO. To our knowledge, this is the first report of a γ 3-proteobacterium affecting strawberry in Italy. In the genome region analyzed, our isolates are more similar to the SBR BLO than to 'Ca. P. fragariae'. Further work is in progress to investigate incidence, geographical distribution, epidemiology, and host range of this pathogen in Italy. References: (1) J. L. Danet et al. Phytopathology 93:644, 2003. (2) O. Semetey et al. Phytopathology 97:72, 2007. (3) F. Terlizzi et al. Plant Dis. 90:831, 2006.

First Report of a 16SrII Group Phytoplasma Associated with Shoot Proliferation of a Cactus (Opuntia monacantha) in Lebanon.

In October 2003, during a survey to evaluate the incidence of phytoplasma diseases in Lebanon, symptoms suggestive of phytoplasma infection in Opuntia monacantha (Haworth) were observed in Saghbine, Bekaa Valley. Symptoms were excessive stem and shoot proliferation. Three symptomatic and as well as symptomless plants were collected and analyzed for the presence of phytoplasmas. Nucleic acids were extracted from 0.5 g of shoot tissue and tested using polymerase chain reaction (PCR) with universal phytoplasma primers (fU5rU3) for partial amplification of the ribosomal 16SrDNA (4). PCR resulted in amplification of an expected 881-bp rDNA fragment from the symptomatic but not from symptomless samples. For characterization, sequence of the amplified DNA was determined (Genbank Accession No. AY939815). The sequence showed a high similarity with several isolates of the 16srII group of phytoplasmas. The highest similarity has been oserved with 16S rDNA of two isolates of cactus witches'-broom phytoplasma found in China (1) and Mexico (3) (Genbank Accession Nos. AJ293216 and AF320575, respectively) (99.8%) as well as faba bean phyllody phytoplasma (Genbank Accession No. X83432) (99.7%) and "Candidatus Phytoplasma aurantifolia" (Genbank Accession No. U15442) (99.3%). The presence of phytoplasmas was confirmed using nested-PCR with primers R16mF2/R1 and R16F2n/R2 (2). The Tru9I digestion pattern of the amplified product R16F2n/F16R2 detected in O. monacantha was identical to the digestion pattern obtained from periwinkle infected by "Ca. P. aurantifolia" (subgroup 16SrII-B) and soybean phyllody phytoplasma (subgroup 16SrII-C), but different from the Tru9I digestion pattern observed for cleome phyllody phytoplasma (subgroup 16SrII-A) and tomato big bud phytoplasma (subgroup 16SrII-E). To our knowledge, this is the first report of an infection with a phytoplasma belonging to16SrII group in Lebanon. References: (1) H. Cai et al. Plant Pathol. 51:394, 2002. (2) D. E. Gundersen and I. M. Lee. Phytopathol. Mediterr. 35:144, 1996. (3) N. E. Leyva-Lopez et al. Phytopathology. (Abstr.) 89(suppl):S45, 1999. (4) B. Schneider et al. Pages 369-380 in: Molecular and Diagnostic Procedures in Mycoplasmology. Academic Press, NY, 1995.

First Report of Grapevine "Bois Noir" Disease and a New Phytoplasma Infecting Solanaceous Plants in Lebanon.

During a 2001 survey to evaluate the incidence of phytoplasma diseases in Lebanon, samples were collected from plants showing symptoms suggestive of phytoplasmal infections. Samples were also collected from symptomless plants. Sampled hosts from the Bekaa Valley included: 3 samples of tomato (Lycopersicum esculentum), 4 samples of pepper (Capsicum annuum), 10 samples of grapevine (Vitis vinifera) cvs. Chardonnay and Alicante Bouschet; 7 samples of ornamental periwinkle (Catharantus roseus) from the Tyr area; and 4 samples of weeds (Lactucca serratia). DNA was extracted from leaf midveins of diseased and symptomless plants, and from healthy periwinkle, grapevine, tomato, and pepper plants grown in a greenhouse in France. Polymerase chain reaction (PCR) with universal primers for the amplification of phytoplasma ribosomal RNA genes (3) only produced a 1.8-kbp rDNA fragment from symptomatic samples. The amplified DNAs were analyzed by restriction fragment length polymorphism (RFLP) with several restriction enzymes and sequenced. The analysis showed extracts of diseased grapevines, and two periwinkle plants had identical rDNA sequences and restriction profiles of the stolbur cluster (4). The sequences had 98% identity with two European stolbur isolates from grapevine and periwinkle (GenBank Accession Nos. X76428 and AF248959, respectively). In grapevine, the disease induced by the stolbur phytoplasma is "bois noir." Bois noir is present in Europe where its incidence is predominant in northern vineyards and has been reported in Israel (2). To our knowledge, this is the first report of the stolbur/bois noir disease in Lebanon. In tomato and pepper, the restriction profiles and sequences of the phytoplasma rDNAs were identical. Sequencing and phylogenetic analysis indicated that the phytoplasma belonged to the clover proliferation (CP) cluster, as does the eggplant little leaf phytoplasma of solanaceous plants in Asia. They differed from the stolbur phytoplasma, known to infect solanaceaous plants in Europe. Lastly, a phytoplasma belonging to the pigeon pea witches' broom (PPWB) cluster was found in L. serratia and in some periwinkle plants. A phytoplasma of the PPWB cluster was recently shown to be responsible for an emerging lethal disease of almond trees in Lebanon (1). References: (1) E. Choueiri et al. Plant Dis. 85:802, 2001. (2) X. Daire et al. Vitis 36:53, 1997. (3) B. Schneider et al. Pages 369-380 in: Molecular and Diagnostic Procedures in Mycoplasmology. Academic Press, NY, 1995. (4) E. Seemüller et al. J. Plant Pathol. 80:3, 1998.

Comparing the spatial genetic structures of the Flavescence dorée phytoplasma and its leafhopper vector Scaphoideus titanus.

The Nearctic leafhopper Scaphoideus titanus Ball is the vector of "Flavescence dorée" phytoplasma (FDp) in European vineyards. We studied the genetic diversity and structure of S. titanus populations in France and of the FDp they carried. A total of 621 S. titanus individuals, sampled in 24 FDp-infected and uninfected vineyards, were genotyped using seven polymorphic microsatellite loci. The mean observed heterozygosity in S. titanus populations was between 0.364 and 0.548. There was evidence of only a low level of population genetic differentiation (mean F(ST)=0.027) suggesting that there is long-distance gene flow between S. titanus populations. This may be a consequence of the high migration capacity of the vector associated with large effective population size and, at least in part, of passive dispersion over long distances by the transport of grapevine-planting material carrying eggs. For each insect, FDp was detected and typed by nested-PCR followed by RFLP and sequencing of a 674 bp fragment of the FDp map gene. Twelve of the 24 populations were found to be infected by FDp, with the percentage of infected individuals varying from 3% to 29%. FDp isolates were classified into two FDp genetic clusters (FD1 and FD2), which differed by 12-13 SNPs. FD1 genotypes were detected in the insect populations at two sites and the FD2 genotypes in the other ten populations. Both FD1 and FD2 genotypes were found to be transmitted by the insect. No significant relationship was found between the genetic structure of these French S. titanus populations and the distribution of the various FDp strain types they carried. Nevertheless, overall genetic differentiation between FDp-infected and healthy S. titanus "subsamples" was found to be significantly higher than zero. These results suggest that FDp-infected S. titanus individuals are more philopatric (disperse less) than healthy S. titanus.