Intravascular papillary endothelial hyperplasia (Masson's tumor) of the conjunctiva. Unusual location of a rare vascular tumor.

Intravascular papillary endothelial hyperplasia (IPEH) is characterized by proliferation of endothelial cells usually occurring within a long-standing vascular malformation or tumor. IPEH usually affects neck, head and lower extremities, and few orbital and eyelid cases have been reported. We present a unique case, a 48-years-old man with a purple, elevated, multilobular conjunctival lesion of three-weeks duration that underwent an excisional biopsy. Pathological features revealed intravascular papillary endothelial hyperplasia (Masson's tumor).

At least 27 alternatively spliced forms of the neural cell adhesion molecule mRNA are expressed during rat heart development.

The major membrane-associated or transmembrane isoforms of the neural cell adhesion molecule (NCAM) are generated by alternative splicing at the 3' end of the mRNA. Further diversity in NCAM structure is observed in the extracellular region of the polypeptide, where the insertion of additional amino acid residues can result from alternative splicing events occurring at the exon 7-exon 8 and exon 12-exon 13 junctions. Here we report the characterization of tissue-specific patterns of alternative splicing at the exon 12-exon 13 junction by using the polymerase chain reaction. Nine alternatively spliced sequences in rat heart between exon 12 and exon 13 were identified. Each sequence consisted of different combinations of the three small exons (15, 48, and 42 bp in length) and the AAG triplet that make up MSD1, the 108-bp muscle-specific sequence found in human skeletal muscle NCAM (G. Dickson, H.J. Gower, C. H. Barton, H. M. Prentice, V. L. Elsom, S. E. Moore, R. D. Cox, C. Quinn, W. Putt, and F. S. Walsh, Cell 50:1119-1130, 1987). Although the rat equivalent of MSD1 (designated 15+ 48+ 42+ 3+) was detected in all ages of heart examined, it was only one of four or five major splice combinations at any given age. The only alternatively spliced sequence found in the exon 7-exon 8 junction of heart NCAM mRNA was the 30-bp variable alternatively spliced exon previously identified in rat brain. Twenty-seven NCAM forms with distinct sequences were found by analysis of individual NCAM transcripts from postnatal day 1 heart tissue for alternative splicing at the exon 7-exon 8 junction, the exon 12-exon 13 junction and the 3' end. Several combinations of splicing patterns in these three different regions of the gene appeared to be preferentially expressed. The observation that the expression of alternatively spliced forms of NCAM is developmentally regulated suggests a role for NCAM diversity in cardiac development.

Identification of the cloned gene for the murine transplantation antigen H-2Kb by hybridization with synthetic oligonucleotides.

The H-2K(b) gene is a member of the large major histocompatibility complex class I gene family. Since many members of this family cross-hybridize with class I cDNA probes, the cloned H-2K(b) gene was identified by hybridization with specific oligonucleotide probes. This clone was definitively shown to encode the H-2K(b) polypeptide by partial DNA sequencing and by serological and tryptic peptide analyses of the expressed product.

[Atypical frontal sinus mucocele. A case report]. / Mucocele del seno frontal de presentación atípica. Informe de un caso.

CLINICAL CASE: We report a case of a 46-year-old woman who developed a tender, painful mass in the left superior eyelid over a period of about 6 months. This was a frontal mucocele with atypical clinical and histopathologic features. DISCUSSION: Most mucoceles arise from the frontal or ethmoidal sinuses. Frontal mucoceles usually cause outward and downward displacement of the globe, and are often associated with fullness in the supero-nasal and medial canthal region and a palpable mass.

[Seborrheic keratosis of conjunctiva: a case report]. / Queratosis seborreica de la conjuntiva: informe de un caso.

CASE REPORT: Pigmented conjunctival lesions are a diagnostic challenge for the clinician. A 37-year-old man presented with a pigmented mass involving the conjunctiva of his right eye. Clinically, a diagnosis of malignant melanoma was made and a wide excision of the tumor was performed. The histopathologic diagnosis was seborrheic keratosis. DISCUSSION: Seborrheic keratosis is a benign lesion which occurs on the eyelids and face of middle-aged and elderly individuals. The occurrence of this lesion on the conjunctiva is rare, however there are 2 cases reported in the world literature. Seborrheic keratosis should be considered in the differential diagnosis of conjunctival pigmented lesions.

[Corneal macular dystrophy: clinical, histopathologic and ultrastructural features]. / Distrofia macular corneal: características clínicas, histopatológicas y ultraestructurales.

OBJECTIVE: To assess the main clinical, genetic, histopathological and ultrastructural features of Mexican patients with macular corneal dystrophy, and to compare the results with those previously reported. METHOD: We analyzed six cases where a histopathologic diagnosis of macular corneal dystrophy had been made between 1957 and 2004. RESULTS: Clinically, all corneas showed focal grayish-white stromal opacities with diffuse edges. Histopathologically, intrastromal granules stained strongly positive with Alcian blue and colloidal iron. Transmission electron microscopy showed enlargement of smooth endoplasmic reticulum and the presence of intracytoplasmic vacuoles that corresponded to glycosaminoglycans. Genetic analysis showed novel mutations in the CHST6 gene in 2 of the patients. CONCLUSIONS: Females were more affected than males and the mean age at the time of diagnosis was older than that reported previously, however the clinical, histopathological and ultrastructural features were similar to those of previous reports. As described in other cases in the literature, in some instances a disorder is found in CHST6 gene as a basis for this condition.

Retinoblastoma in the adolescent. Unusual clinical and histopathology findings.

CASE REPORT: A 17-year- old male with 2years history of an intraocular mass and progressive visual loss of the left eye. Spontaneous sclera rupture occurred during enucleation. Microscopic evaluation with H-E, PAS and immunohistochemistry (NSE, GAFP, SYN, CD99) revealed a small blue round cell malignant neoplasm with extensive necrosis and apoptosis. The optic nerve, ciliary body, choroid, anterior chamber, and sclera were infiltrated. SYN was positive and CD99 was negative in neoplastic cells, consistent with a poorly differentiated retinoblastoma. DISCUSSION: Retinoblastoma is the most frequent primary intraocular malignant tumour in childhood, but occasionally older patients can be affected. Immunohistochemistry is mandatory in poorly differentiated retinoblastomas.

Cardiovascular effects and safety of dental anesthesia and dental interventions in patients with recent uncomplicated myocardial infarction.

To determine the cardiovascular effects and safety of dental anesthesia and dental interventions in patients within three weeks of uncomplicated acute myocardial infarction, 40 patients were studied. Twenty patients, group 1, underwent injectable local dental anesthesia with 2% lidocaine and 1:100 000 epinephrine. Group 2, 20 patients, underwent vigorous dental prophylaxis (13 patients) or dental extraction (seven patients) after local anesthesia. Heart rate, blood pressure, electrocardiograms, and symptoms were monitored before, during, and after the dental intervention. There were no significant hemodynamic changes or complications related to dental anesthesia or the dental procedures. One patient experienced an asymptomatic, uncomplicated, self-limited, eight-beat run of ventricular tachycardia two hours after dental extraction. Limited dental anesthesia and dental interventions were well tolerated by these patients with recent myocardial infarction.

Identification of the GABAA receptor subtype mRNA in human pancreatic tissue.

Evidence suggests a physiological role of the GABAA receptor in the pancreas. Clinically, an autoimmune reaction involving the GABA biosynthesizing enzyme, glutamic acid decarboxylase has been implicated in the development of insulin-dependent diabetes mellitus. To determine the subtypes of GABAA receptor expressed in human pancreas, we analyzed, with the use of the reverse-transcription/polymerase chain reaction technique human pancreatic tissue for the presence of GABAA receptor subunits alpha 1-6, beta 1-3, and gamma 1-2 transcripts. Unlike brain tissue, pancreatic tissue only expresses the alpha 2, beta 3 and gamma 1 subunits. Our results provide evidence of a specific GABAA receptor subtype expressed in human pancreatic tissue.

Distinct NCAM splicing events are differentially regulated during rat brain development.

Primary transcripts for the neural cell adhesion molecule NCAM are highly alternatively spliced potentially giving rise to over 100 different mRNA forms. These mRNAs encode three major polypeptide isoforms of 120, 140, and 180 kDa each of which is thought to be composed of a mixture of polypeptides that differ by the variable presence of small exons at two locations. These NCAM 'microsplicing' patterns were examined within mRNA populations encoding each of the major isoforms to identify exactly which NCAM forms are present during brain development. The proportion of NCAM mRNAs containing at the exon 7/8 junction the alternatively microspliced 30 bp VASE exon increased similarly during brain development in mRNAs encoding all three major size classes. Perinatal brain, cultures of neurons from embryonic rats, and of glia from newborn rats all had low VASE levels while about 50% of the mRNAs in adult brain expressed VASE. In contrast, microsplicing at the exon 12/exon 13 junction was differentially regulated among NCAM major size classes. mRNAs containing microspliced exons totaling 3.15, or 18 base pairs (bp) represented greater than 50% of the total mRNAs encoding the 120 kDa forms at all ages. However, these exons were present in less than 15% of the 140 and 180 kDa encoding mRNAs in rats older than embryonic day 15. Similar results at the exon 12/13 junction were observed with mRNAs from neuronal cultures while glial cultures had greater levels of a 3 bp pair exon at this junction.(ABSTRACT TRUNCATED AT 250 WORDS)

Structure of the human gastric H,K-ATPase gene and comparison of the 5'-flanking sequences of the human and rat genes.

We have isolated and analyzed the genes encoding the human and rat gastric H,K-ATPase catalytic subunits. The complete sequence of the human gene, including 2.2 kb of 5'-flanking sequence, and the 5' end of the rat gene, including exons 1-4 and 2.5 kb of 5'-flanking sequence, have been determined. The human gene contains 22 exons. Its intron-exon organization is identical to that of the Na,K-ATPase gene, except that exon 6 corresponds to a fusion of exons 6 and 7 of the Na,K-ATPase gene. The transcription initiation sites of both the human and rat genes were determined by primer extension and S1 nuclease protection analyses. Comparison of the 5'-flanking regions of the human and rat genes revealed three extended regions of high sequence similarity, one of which includes a potential TATA box and other basic promoter elements beginning about 30 nucleotides upstream of the transcription start site. Other conserved sequences, including possible response elements for Ca2+ and cAMP, which are known intracellular mediators of acid secretion, are located up to 2 kb 5' to the transcription initiation site.

Enteropathogenic bacteria in the La Paz River of Bolivia.

Diarrheal diseases often result from ingestion of contaminated water or food. The population of La Paz, Bolivia is directly or indirectly exposed to the sewage-contaminated La Paz River. We conducted a bacteriologic survey of the La Paz River to quantify the level of bacterial contamination, with particular reference to enteropathogens. A total bacterial count exceeding 10(6) colony-forming units (CFU)/ml, including lactose fermenting and nonfermenting, gram-negative bacilli of approximately 10(5) CFU/ml, respectively, were detected in river water samples collected near two densely populated areas. A total bacterial count of 10(5) CFU/ml was also detected at the most downstream area of the river near a sparsely populated area. At four sampling locations, several enteropathogens were detected, including five enterotoxigenic Escherichia coli (ETEC) (serotype O6, O15, and O159), two enteropathogenic E. coli (EPEC) (serotype O44), two enteroinvasive E. coli (EIEC) (serotype O29), and three Salmonella O4 group isolates. The heat-labile enterotoxin gene and the invasive toxin gene were detected in all ETEC and EIEC isolates by polymerase chain reaction analysis. Nine isolates of E. coli were found by the agar dilution method to be susceptible to ampicillin, kanamycin, nalidixic acid, tetracycline, and chloramphenicol, and ampicillin resistance was found in only two isolates of EIEC 7-4 (serotype O29) and EPEC 7-5 (serotype O44). Ampicillin resistance was coded on plasmids and transferred conjugatively to E. coli chi1037 at a frequency of 10(-5) CFU/donor by the broth mating method. Strains of Aeromonas caviae, which can cause diarrheal disease in infants, were detected in vegetables grown in fields irrigated by water from the La Paz River. The survival of nine isolates of E. coli in filtered river water was compared with that of laboratory strains (E. coli chi1037, W3110, and ATCC29577). The survival time of seven isolates, excluding two ampicillin-resistant isolates, was markedly longer than that of the laboratory strains. Our results show a high bacterial contamination of the La Paz river and suggest that such levels may contribute to the high incidence of diarrheal disease in the city of La Paz.

Stable high expression of human gamma-aminobutyric acidA receptors composed of alpha and beta subunits.

Multiple classes of pharmacological agents including benzodiazepines, cage convulsants like t-butylbicyclophosphorothionate (TBPS), barbiturates and neuroactive steroids allosterically modulate the gamma-aminobutyric acidA receptor-chloride ionophore complex (GRC). The function of benzodiazepines requires a GRC comprised of alpha, beta and gamma subunits, while TBPS, barbiturates and neuroactive steroids will allosterically modulate GRCs comprised of only alpha and beta subunits. Binary alpha beta complexes are still hypothesized to be expressed in the mammalian brain particularly during development and could contribute to the pharmacological action of neuroactive steroids and barbiturates. In order to examine binary alpha beta complexes we report here the establishment of stable cell lines that express high levels of human GABAA receptors comprised of alpha 1 beta 1, alpha 2 beta 1 and alpha 3 beta 1 subunit combinations. The apparent potencies for allosteric modulation of [35S]TBPS for most naturally occurring neuroactive steroids for the binary subunit combinations was similar to that of the gamma-containing subunit combinations. Also discussed is the usefulness of these cell lines for the biophysical analysis of the GABAA receptor stoichiometry.

One-year clinical performance of a resin-modified glass ionomer and a resin composite restorative material in unprepared Class V restorations.

This study evaluated the clinical performance and appearance of a resin-modified glass ionomer and a resin composite over one year. Thirty-seven pairs of restorations of Fuji II LC and Z250/Single Bond were placed in caries-free cervical erosion/abfraction lesions without tooth preparation. Restorations were clinically evaluated at baseline and 6 and 12 months, using modified Ryge/USPHS criteria. No significant difference (p>0.05) was observed in performance of both materials, although retention of the Z250 restorations was below the minimum specified in the ADA Acceptance Program for Dentin and Enamel Adhesives. Little difference in the restorations' appearance was observed.

[Clinical-pathologic characteristics of uveal melanoma in Mexican patients under thirty years old]. / Características clínico-patológicas del melanoma uveal en pacientes mexicanos menores de 30 años de edad.

PURPOSE: To analyze the clinicopathologic characteristics of uveal melanoma in Mexican patients under thirty years old. METHODS: We reviewed the cases from the Service of Ophthalmic Pathology with histopathologic diagnosis of uveal melanoma from 1957 to March 2002. The data analyzed were: age, gender, affected eye, clinical diagnosis, size, cellular type, mitotic index, lymphocytic infiltrate, vascular pattern, necrosis, vascular and/or intraocular invasion and orbital extension. RESULTS: We reviewed 122 cases diagnosed with uveal melanoma, and 14 patients were younger than 30 years old (11.4%). The mean age was 21.7 years, with female preponderance. Preoperative clinical diagnoses were uveal melanoma in 92.8%, most of the cases originated from choroid. The most frequent cellular type was spindle cells and 3 and 4 Folberg's vascular patterns. CONCLUSIONS: Our results suggest that the clinicians should consider uveal melanoma more frequently as another differential diagnosis in patients under thirty years with an intraocular tumor. The histological characteristics found have been correlated with a better prognosis.

Hiperplasia endotelial papilar intravascular (tumor de Masson) de la conjuntiva. Ubicación inusual de un tumor vascular endotelial raro / Intravascular papillary endothelial hyperplasia (Masson's tumor) of the conjunctiva. Unusual location of a rare vascular tumor

La hiperplasia endotelial papilar intravascular (IPEH) se caracteriza por la proliferación de células endoteliales generalmente producida dentro de una malformación vascular previa o un tumor. La IPEH suele afectar cuello, cabeza y extremidades inferiores, se han publicado pocos casos en la órbita ocular y párpados. Presentamos un caso único, un hombre de 48 años con una lesión conjuntival púrpura, elevada y multilobular de tres semanas de duración que se sometió a una biopsia excisional. Las características patológicas revelaron una hiperplasia endotelial papilar intravascular (tumor de Masson) (AU)

Intravascular papillary endothelial hyperplasia (IPEH) is characterized by proliferation of endothelial cells usually occurring within a long-standing vascular malformation or tumor. IPEH usually affects neck, head and lower extremities, and few orbital and eyelid cases have been reported. We present a unique case, a 48-year-old man with a purple, elevated, multilobular conjunctival lesion of three-weeks duration that underwent an excisional biopsy. Pathological features revealed intravascular papillary endothelial hyperplasia (Masson's tumor) (AU)

Populations of the spinach wilt pathogen, Fusarium oxysporum f. sp. spinaciae, in the root tissues, rhizosphere, and soil in the field.

Populations of Fusarium oxysporum f. sp. spinaciae in root tissues and rhizosphere soil of diseased spinach plants were higher than in the root tissues and rhizosphere soil of healthy plants. Populations in soil rhizosphere were higher than in nonrhizosphere soil. The fungus populations were very low in the root tissues of the nonsusceptible strawberry, broccoli, chinese cabbage, and mustard grown in the infested field. The populations were low at the beginning of the season, increased, and remained high during the summer, then dropped in the fall. The fungus populations ranged from 1600 to 2600 propagules/g in the top 10 cm of soil, declined sharply between 11 and 20 cm, and were nondetectable between 41 and 60 cm.

Generation of multiple independent substitution mutants by M13 in vitro mutagenesis using a single mutagenic oligonucleotide.

A 56-nucleotide mutagenic oligomer containing six mismatches with the wild-type template was used to construct multiple transversion mutations in the putative heparin binding region of the rat neural cell adhesion molecule (NCAM) cDNA sequence. Mutants were screened by hybridization to the 56-mer. The relative stability of a mutant DNA:56-mer duplex correlated with the number of base substitutions present in the mutant sequence. Five independent categories of mutants carrying from two to five of the expected nucleotide substitutions were isolated. No mutations other than those directed by the 56-mer were observed. These results suggest a method for generating sets of related predefined substitution mutants.

Bladder contributes to eicosanoids excreted in urine.

The excretion of eicosanoids was examined in urine collected from the bladder or the ureter in normal rats. We found that the excretion of thromboxane B2 (the stable metabolite of thromboxane A2), prostaglandin E2, and 6-ketoprostaglandin F1 alpha was significantly greater in urine collected from the bladder than in urine collected from the ureter. This suggests that the bladder contributes significantly to the amount of eicosanoids present in the urine.