First Report of Tomato yellow leaf curl virus Infecting Tomato, Tomatillo, and Peppers in Guatemala.

In Guatemala and other Central American countries, whitefly-transmitted geminiviruses (begomoviruses) cause economically important diseases of tomato (Solanum lycopersicum) and pepper (Capsicum annuum). Disease symptoms include stunted and distorted growth and leaf curling, crumpling, light green to yellow mosaic, purpling, and vein swelling. In Guatemala, at least eight bipartite begomovirus species infect tomato or peppers (1), but their role and relative importance is unclear. As part of an Integrated Pest Management strategy to manage these diseases, surveys for begomovirus symptoms in pepper and tomato have been conducted in the Salama Valley, Sanarate, and other locations since 2003, and begomoviruses were identified by squash blot hybridization, PCR and DNA sequencing. Beginning in 2006, a new type of symptom, stunted upright growth and upcurled leaves with yellowing of the margins and interveinal areas, was observed in tomato and tomatillo plants in the Salama Valley and Sanarate. These symptoms were similar to those induced by the exotic monopartite begomovirus Tomato yellow leaf curl virus (TYLCV). Evidence that TYLCV caused these symptoms came from positive results in high stringency squash blot hybridization tests with a TYLCV probe, and amplification of the expected size of ~0.3- and 2.8-kb fragments in PCR tests with TYLCV capsid protein (CP) gene and full-length component primer pairs, respectively (3). Sequence analyses of PCR-amplified CP fragments and portions of full-length fragments revealed 97 to 99% identity with isolates of TYLCV-Israel (TYLCV-IL). The complete nucleotide sequence of an isolate from the Salama Valley (GenBank Accession No. GU355941) was >99% identical to those of TYLCV-IL isolates from the Dominican Republic, Florida, and Cuba and ~97% identical to those of isolates from Mexico and California. Thus, this TYLCV-IL isolate (TYLCV-IL[GT:06]) was probably introduced from the Caribbean Region. To further characterize begomoviruses in the Salama Valley, leaf samples were collected from 44 and 118 tomato plants showing symptoms of begomovirus infection in March 2006 and 2007, respectively, and from 106 symptomatic pepper plants in March 2007. Begomovirus infection was confirmed in 42 of 44 and 93 of 118 of the tomato samples and 100 of 106 of the pepper samples based on PCR amplification of the expected size of ~0.6- and 1.1-kb DNA fragments with the begomovirus degenerate primers pairs AV494/AC1048 and PAL1v1978/PAR1c496, respectively (2,4). Sequence analyses of cloned PCR-amplified fragments revealed that 3 of the 44 and 16 of the 118 tomato samples collected in 2006 and 2007, respectively, and 9 of the 106 pepper samples were infected with TYLCV based on >97% identity with TYLCV-IL. In all samples, TYLCV was present in mixed infections with other begomoviruses. The introduction of TYLCV adds to the already high level of genetic complexity of bipartite begomovirus infection of tomatoes and peppers in Guatemala and will undoubtedly complicate disease management efforts. References: (1) M. K. Nakhla et al. Acta Hortic. 695:277, 2005. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993. (3) R. Salati et al. Phytopathology 92:487, 2002. (4) S. D. Wyatt and J. Brown. Phytopathology 86:1288, 1996.

CNGA3 mutations in hereditary cone photoreceptor disorders.

We recently showed that mutations in the CNGA3 gene encoding the alpha-subunit of the cone photoreceptor cGMP-gated channel cause autosomal recessive complete achromatopsia linked to chromosome 2q11. We now report the results of a first comprehensive screening for CNGA3 mutations in a cohort of 258 additional independent families with hereditary cone photoreceptor disorders. CNGA3 mutations were detected not only in patients with the complete form of achromatopsia but also in incomplete achromats with residual cone photoreceptor function and (rarely) in patients with evidence for severe progressive cone dystrophy. In total, mutations were identified in 53 independent families comprising 38 new CNGA3 mutations, in addition to the 8 mutations reported elsewhere. Apparently, both mutant alleles were identified in 47 families, including 16 families with presumed homozygous mutations and 31 families with two heterozygous mutations. Single heterozygous mutations were identified in six additional families. The majority of all known CNGA3 mutations (39/46) are amino acid substitutions compared with only four stop-codon mutations, two 1-bp insertions and one 3-bp in-frame deletion. The missense mutations mostly affect amino acids conserved among the members of the cyclic nucleotide gated (CNG) channel family and cluster at the cytoplasmic face of transmembrane domains (TM) S1 and S2, in TM S4, and in the cGMP-binding domain. Several mutations were identified recurrently (e.g., R277C, R283W, R436W, and F547L). These four mutations account for 41.8% of all detected mutant CNGA3 alleles. Haplotype analysis suggests that the R436W and F547L mutant alleles have multiple origins, whereas we found evidence that the R283W alleles, which are particularly frequent among patients from Scandinavia and northern Italy, have a common origin.

Checklist for the evaluation of low vision in uncooperative patients.

PURPOSE: To present a checklist for the evaluation of low vision in uncooperative patients; in this specific case, children with neurological deficits. METHOD: The checklist includes several behavioral indicators obtainable with a standard clinical examination. Each test is assigned a score (0=failure, 1=success). The final visual quotient score is obtained by dividing the partial score by the total number of tests performed. Eleven children with cerebral visual impairment were studied using behavioral and preferential looking techniques. RESULTS: Visual quotient was >0 in all patients, indicating that residual visual function was always detectable. Average visual quotient was 0.74. CONCLUSION: Visual quotient can be useful both for follow-up examinations and comparison and integration with other evaluation methods (behavioral and instrumental) of residual visual capacity. In particular, if combined with preferential looking techniques, visual quotient testing permits characterization of the entire spectrum of low vision.

Functional analysis of proteins involved in movement of the monopartite begomovirus, Tomato yellow leaf curl virus.

The functional properties of proteins [capsid protein (CP), V1, and C4] potentially involved with movement of the monopartite begomovirus, Tomato yellow leaf curl virus (TYLCV), were investigated using microinjection of Escherichia coli expressed proteins and transient expression of GFP fusion proteins. The TYLCV CP localized to the nucleus and nucleolus and acted as a nuclear shuttle, facilitating import and export of DNA. Thus, the CP serves as the functional homolog of the bipartite begomovirus BV1. The TYLCV V1 localized around the nucleus and at the cell periphery and colocalized with the endoplasmic reticulum, whereas C4 was localized to the cell periphery. Together, these patterns of localization were similar to that of the bipartite begomovirus BC1, known to mediate cell-to-cell movement. However, in contrast to BC1, V1 and C4, alone or in combination, had a limited capacity to move and mediate macromolecular trafficking through mesophyll or epidermal plasmodesmata. Immunolocalization and in situ PCR experiments, conducted with tomato plants at three stages of development, established that TYLCV infection was limited to phloem cells of shoot apical, leaf, stem, and floral tissues. Thus, the V1 and/or C4 may be analogs of the bipartite begomovirus BC1 that have evolved to mediate TYLCV movement within phloem tissue.

Evolution of ocular clinical and electrophysiological findings in pediatric Bardet-Biedl syndrome.

Bardet-Biedl syndrome (BBS) is a hereditary autosomal-recessive disorder, characterized by mental retardation, obesity, pigmentary retinopathy, polydactyly and, only in males, hypogenitalism. Even though genetic studies have revealed five different forms of BBS correlated to distinct loci on different chromosomes, a diagnosis of BBS is still primarily based on clinical data. The present study discusses the evolution of clinical ophthalmological and electrophysiological characteristics of BBS patients in developmental age. The main results obtained on a sample of 13 pediatric patients are the following: * progressive loss of visual acuity arised early in the first decade of life * ophthalmoscopic signs of pigmentary retinopathy were present only in 46% of the children studied * striking anomalies in the electroretinogram were also detected in the cases without pigmentary retinopathy * the electroretinographic results, when detectable, suggested a greater involvement of the photopic system as against the scotopic system.

Cerebral visual impairment in periventricular leukomalacia.

Infants with cerebral palsy (CP) frequently present cerebral visual impairment (CVI) often caused by damage to retrochiasmatic pathways. This is particularly true of subjects with damage to the periventricular white matter. Thirty-eight preterm infants with periventricular leukomalacia (PVL) diagnosed by MRI were examined to correlate binocular visual acuity with neuroradiological findings. Binocular visual acuity was evaluated using Teller Acuity Cards and a complete ophthalmological examination was also performed. Three infants with ROP III were excluded from the sample. The age of observation ranged from 20 months to 5 and a half years (mean 42 months). The possible involvement of the optic radiations and/or of the calcarine cortex was detected by brain MRI. Twenty-three infants (66%) presented visual impairment. Of these, 9 (26%) were totally or nearly totally blind and 14 (40%) were low vision children. The other 12 (34%) had normal (2) or near normal (9) vision. MRI findings correlated with visual acuity; a relationship was detected between the degree of visual acuity and the reduction of the peritrigonal white matter, and also between the degree of visual acuity and the extent of calcarine atrophy. This report clearly establishes a relationship between visual impairment and specific MRI findings in children with PVL. Teller Acuity Cards and MRI are useful for detecting potential visual impairment and for improving both the clinical diagnosis of these disorders and the therapeutic approach to these subjects.

Transient nystagmus in delayed visual maturation.

Two infants who presented with wide-amplitude and high-frequency nystagmus and lack of visual awareness in the first 3 months of life were studied. No ocular abnormalities were found. Neurodevelopmental examination, visual evoked potentials and electroretinograms were normal. One infant underwent MRI which resulted in normal findings. Two months later both patients showed increased visual responsiveness and a gradual reduction of the nystagmus amplitude. By 5 months of age nystagmus was no longer detectable and both infants appeared to be visually, developmentally, and neurologically normal. Follow-up at 3 years of age for subject 1 and at 11 months for subject 2 showed that both the infants maintained the normal ophthalmological and neurological assessments. We diagnosed delayed visual maturation with oculomotor involvement.

A pigmented free-floating vitreous cyst in a six-year-old child.

We observed a unilateral free-floating vitreous cyst in a 6-year-old boy. The ophthalmologic examination was otherwise normal. The cyst, which was pigmented, had a diameter of approximately 2.5 mm and was localized in the anterior vitreous of the left eye. In its movements it occasionally affected the visual axis, causing only transient and sporadic blurring of vision. Visual acuity in the affected eye was equal to that in the other eye (20/20). Follow-up is by periodic examinations.

Electronystagmographic investigation in X-linked ocular albinism.

Albinism represents the most frequent cause of nystagmus induced by visual sensory disorders. We studied five patients aged between three and five years with ocular albinism with the aim of identifying the characteristics of nystagmic oscillations. The patients underwent complete ophthalmological examination and electronystagmography (ENG). ENG revealed either pendular or jerk waveforms (or both) with the same complex effects of fixation seen in those with idiopathic congenital nystagmus. Three children presented face turn due to reduced severity of nystagmus in lateroversion. Latent nystagmus was not observed.

Esotropia and pseudoexotropia in acute ROP sequelae: clinical features and suggestions for treatment.

We report five cases with a mixture of esotropia and pseudoexotropia due to macular ectopia related cicatricial retinopathy of prematurity (ROP). On inspection, the patients, aged from 9 to 28 years, presented a divergence of the eyes and a nasally decentralised corneal light reflex. The cover test showed esodeviation. All the cases presented some clinical features common to congenital strabismus. Fundus examination showed temporal traction of vascular and retinal tissues and macular ectopia, referrable to cicatricial sequelae of spontaneously regressed severe ROP. Treatment is limited to follow-up, with attention being paid to the control of retinal damage rather than to resolving the esthetic defects. Despite cryotherapy, these conditions are increasing with the increase in severe ROP and are now relatively frequent. We suggest that they be carefully identified in order to avoid incorrect orthoptic or surgical treatment.

Review of experience with retinopathy of prematurity from the Pavia registry (1990-1993).

In this retrospective study we analysed the prevalence of retino-pathy of prematurity (ROP) and its sequelae in a sample of premature infants with birth weight less than 1500 grams. From 1 January 1990 to 31 October 1993, we studied 160 surviving premature infants with very low birth weight (< 1.500 g) referred to the Neonatal Intensive Care Unit of the I.R.C.C.S. Policlinico San Matteo, Pavia, Italy. Thirty percent of these infants suffered from ROP, and 13.7%, with severe ROP, underwent cryotherapy. These latter had very-very low birth weight (< 1.000 g) and low gestational age (< 28 weeks). Follow-up of 69 infants at 12 months for retinal sequelae, refraction defects, bin-ocular vision and ocular motility impairments gave the following results: 1) strabismus 20.3%; 2) > 3D hyperopia 3%; 3) myopia 30.4%; 4) > 5D myopia 3.7%. The incidence of refraction and ocular motility anomalies in patients with acute ROP with spontaneous remission was similar to that of unaffected premature infants. Conversely, in the patients treated with cryotherapy the incidence of strabismus and > 5D myopia was greater than for untreated infants: 30% vs 15.4% (n.s.) and 14.7% vs 0% (p = 0.05), respectively. Cryotherapy was successful in 91.9% of cases and in 37.8% of cases the cicatricial sequelae were limited to peripheral chorioretinal scars.

[Unilateral congenital cataract and visual function]. / Cataracte congénitale unilatérale et fonction visuelle.

The authors report the case of a young patient presented with cytomegalovirus infection involving the nervous, respiratory and ocular systems. A congenital monocular cataract associated with a chorioretinal macular scar in the controlateral eye imposed surgical treatment of the cataract. No retinal damages were found in the cataractous eye after surgery. Three years later the visual function is supported by the phakic eye in spite of the relative precocity of surgery (4th month), and of the correct antiambliopic treatment. This case would suggest that the period in which a monocular cataract can be treated with good functional results, should be restricted within the first few weeks of life.

Brown's syndrome associated with Smith-Magenis syndrome: Case report.

Brown's syndrome is generally an isolated clinical condition. The authors observed a girl with a right Brown's syndrome and a rare condition due to an interstitial deletion of chromosome 17, known as Smith-Magenis syndrome. A wide spectrum of congenital disorders have been reported in Smith-Magenis syndrome, but never Brown's syndrome.

Sporadic Duane's Retraction Syndrome Associated with Imperforate Anus: Case Report.

Duane's retraction syndrome is sometimes associated with developmental ocular and extraocular abnormalities. This disorder may also be present in association with specific malformative syndromes. The authors report the clinical features of a seven-year-old female affected by Duane's retraction syndrome (D.R.S.), rectoperineal fistula, imperforate anus and other congenital malformations. From two extensive reviews of 106 reports published before 1982 and from a search (using Medline 1981-1994) for reports of congenital malformations associated with this syndrome, no cases of sporadic D.R.S. associated with the perineal malformations mentioned were found, even though imperforate anus is considered the commoner of hindgut malformation.

Failure to detect genomic material of HTLV-I or HTLV-II in mononuclear cells of Italian patients with multiple sclerosis and chronic progressive myelopathy.

To contribute to the undecided question if a retrovirus of the human T-cell lymphotropic virus (HTLV) family may be involved in the development of multiple sclerosis (MS), we investigated by the polymerase chain reaction (PCR) the presence of HTLV-I and HTLV-II sequences in the peripheral blood mononuclear cell DNAs from 30 patients affected by MS and 15 by chronic progressive myelopathy. Moreover a control group of 14 blood donors was examined. All these patients were devoid of anti-HTLV-I antibody in the serum and cerebrospinal fluid at ELISA. For the PCR, primers and probes specific for the tax region common to HTLV-I and HTLV-II, for the pol region of HTLV-I, and for the pol region of HTLV-II were used. In spite of the high sensitivity of the technique used, the three groups of subjects were negative for HTLV-I and HTLV-II genomic sequences.

Immunological parameters in aging: studies on natural immunomodulatory and immunoprotective substances.

Several immune parameters--particularly T-cell dependent immune responses--are altered in aged subjects. To test the hypothesis that they may be the consequence of more general age-related lymphocyte biochemical alterations, and particularly of the energy producing system, the effect of L-carnitine and acetyl-L-carnitine on cell proliferation was studied in peripheral blood lymphocytes from donors of different ages. The results showed that phytohaemagglutinin-induced peripheral blood lymphocyte proliferation was markedly increased in L-carnitine- or acetyl-L-carnitine-preloaded lymphocytes from young and especially from old subjects. Cells from aged subjects considerably improved their defective proliferative capability. Preliminary observations suggest that L-carnitine-preloading also protected peripheral blood lymphocytes from old donors when such cells were exposed to an oxidative stress.

Medical treatment of biliary duct stones: effect of ursodeoxycholic acid administration.

Twenty-eight patients with radiolucent biliary duct stones without cholangitis and jaundice were randomly allocated into two treatment groups receiving ursodeoxycholic acid 12 mg/kg (group A) or placebo (group B) in three daily doses for 24 months. In group A stones disappeared completely in seven patients and partially in one; placebo administration had no effect on stone size and three patients of group B (only one of group A) went to surgery for complications. Ursodeoxycholic acid treatment did not adversely affect liver function tests, and alkaline phosphatase decreased. Abdominal and biliary colics also became less frequent in the first six months of therapy in group A, but not in the placebo group. The bile was supersaturated with cholesterol in both groups, but decreased significantly only in patients receiving ursodeoxycholic acid even though the lithogenic index remained high. Cholesterol saturation of bile does not seem to be the only factor determining the dissolution of biliary duct stones which sometimes contain cholesterol as the main component.

Bile acid transformation by the intestinal flora and cholesterol saturation in bile. Effects of Streptococcus faecium administration.

In 8 normal subjects the daily administration for 30 days of at least 750 X 10(6) Streptococcus faecium, a bacteria producing substances acting against Clostridia and other intestinal microorganisms reduced the cholesterol saturation and the molar percentage of deoxycholic acid (DCA) in bile. The percentage of cholic acid (CA) and chenodeoxycholic acid (DCA) increased significantly in feces, whereas lithocholic acid (LCA) decreased from 49.2 to 40.5%. In vitro fecal samples of subjects taking S. faecium transformed more slowly CA to DCA and CDCA to LCA. Moreover, 7-ketolithocholic seems an intermediate step in the biotransformation of CDCA to LCA. During SF administration, the anaerobic bacteria count of feces decreases, whereas aerobic bacteria increase; the changes of fecal flora may reduce the degradation of primary bile acids influencing the bile acid composition in both the bile and the intestine.