Protonation of Nucleobases in Single- and Double-Stranded DNA.

Single-stranded model oligodeoxyribonucleotides, each containing a single protonatable base-cytosine, adenine, guanine, or 5-methylcytosine-centrally located in a background of non-protonatable thymine residues, were acid-titrated in aqueous solution, with UV monitoring. The basicity of the central base was shown to depend on the type of the central base and its nearest neighbours and to rise with increasing oligonucleotide length and decreasing ionic strength of the solution. More complex model oligonucleotides, each containing a centrally located 5-methylcytosine base, were comparatively evaluated in single-stranded and double-stranded form, by UV spectroscopy and high-field NMR. The N3 protonation of the 5-methylcytosine moiety in the double-stranded case occurred at much lower pH, at which the duplex was already experiencing general dissociation, than in the single-stranded case. The central guanine:5-methylcytosine base pair remained intact up to this point, possibly due to an unusual alternative protonation on O2 of the 5-methylcytosine moiety, already taking place at neutral or weakly basic pH, as indicated by UV spectroscopy, thus suggesting that 5-methylcytosine sites in double-stranded DNA might be protonated to a significant extent under physiological conditions.

Delayed Diagnosis of X-linked Lymphoproliferative Syndrome Type 2 in a 17-year-old Male With Severe Crohn's Disease and Recurrent Skin Infections.

X-linked lymphoproliferative syndrome type 2 (XLP2) is a rare genetic primary immunodeficiency disease caused by mutations in the XIAP gene that lead to deficiency of the X-linked inhibitor of apoptosis protein. XLP2 is characterized by dysregulated immune responses and can result in an inflammatory bowel disease (IBD)-like phenotype, a form of monogenic IBD. Patients with XLP2 often succumb to fulminant hemophagocytic lymphohistiocytosis or Epstein-Barr virus infections. Hematopoietic stem cell transplantation (HSCT) is currently the only definitive treatment for XLP2. We report an adolescent with a delayed diagnosis of XLP2 in the setting of severe Crohn's disease diagnosed at age 9 years and recurrent skin infections. He is under evaluation for HSCT. Gastroenterologists must recognize monogenic IBD in patients of all ages with severe disease and signs of an underlying primary immunodeficiency disease. Patients with suspected monogenic IBD should undergo immunologic and genetic analysis at diagnosis to initiate potentially life-saving treatment.

Development and Testing of a New Simplified Endoscopic Mucosal Assessment for Crohn's Disease: The SEMA-CD.

OBJECTIVES: Endoscopic mucosal improvement is the gold standard for assessing treatment efficacy in clinical trials of Crohn's disease. Current endoscopic indices are not routinely used in clinical practice. The lack of endoscopic information in large clinical registries limits their use for research. A quick, easy, and accurate method is needed for assessing mucosal improvement for clinicians in real-world practice. We developed and tested a novel simplified endoscopic mucosal assessment for Crohn's disease (SEMA-CD). METHODS: We developed a 5-point scale for ranking endoscopic severity of ileum and colon based on Simple Endoscopic Score for Crohn's disease (SES-CD). Central readers were trained to perform SES-CD and SEMA-CD. Pediatric patients with Crohn's disease undergoing colonoscopy were enrolled. Video recordings of colonoscopies were de-identified and randomly assigned to blinded central readers. The SES-CD and SEMA-CD were scored for each video. The SES-CD was considered the validated standard for comparison. Correlation was assessed with Spearman rho, inter- and intrarater reliability with kappa statistics. RESULTS: Fifty-seven colonoscopies were read a total of 212 times. Correlation between SEMA-CD and SES-CD was strong (rho = 0.98, P < 0.0001). Inter-rater reliability for SEMA-CD was 0.80, and intrarater reliability was 0.83. Central readers rated SEMA-CD as easier than SES-CD. CONCLUSION: The SEMA-CD accurately and reproducibly correlates with the standard SES-CD. Central readers viewed SEMA-CD as easier than SES-CD. Use of SEMA-CD in practice should enable collecting mucosal improvement information in large populations of patients. This will improve the quality of research that can be conducted in clinical registries. External validation is needed.

Health-related quality of life in the first year after a diagnosis of pediatric inflammatory bowel disease.

BACKGROUND AND AIMS: Assessment of health-related quality of life (HRQOL) is of increasing importance in the evaluation of new therapies for inflammatory bowel disease (IBD). Available data concerning HRQOL in pediatric patients are sparse and uniformly cross-sectional. The aim of this study was to describe HRQOL and influential factors in newly diagnosed pediatric patients with Crohn's disease and ulcerative colitis during the first 12 months after diagnosis. MATERIALS AND METHODS: Participants were drawn from a large, prospectively derived observational IBD registry of pediatric patients studied through 18 U.S. and Canadian centers. Patients who had completed a baseline IMPACT questionnaire and for whom there were 12 months of follow-up data available were included. In addition to description of cohort, factors that were believed to influence HLQOL were assessed during the course of the year from diagnosis. RESULTS: Two hundred eighteen children met inclusion criteria (77% Crohn's disease, 23 % ulcerative colitis, mean age 12.7 +/- 1.9 years). Mean total IMPACT score at baseline was 154, 181 at 6 months, and 191 at 1 year (possible range 0-238, with increasing scores representing better quality of life). Repeated measures analysis showed that age and disease severity significantly negatively affected the IMPACT scores during the course of the year. CONCLUSIONS: In this large prospective pediatric IBD cohort, significant improvement in HRQOL is noted during the year from diagnosis. Mean IMPACT scores varied significantly depending on the disease severity and also decreased with increasing age.

Safety of Secretin Administration in Children.

OBJECTIVE: The aim of this study was to compare the hemodynamic parameters from the anesthesia records of children who underwent upper gastrointestinal endoscopy (esophagogastroduodenoscopy [EGD]) with and without secretin pancreatic function tests (sPFTs). METHODS: The hemodynamic parameters were retrieved from an electronic anesthesia database. The secretin group consisted of 186 children, and the age- and sex-matched control group included 136 patients who did not have sPFTs. RESULTS: There was no difference in the demographic parameters (age and sex) between the 2 groups. The secretin group had a lower height and body mass index. The sPFT resulted in an average 3-minute extension of the endoscopic procedure. The heart rate increased during the EGD in both groups and was higher (averaged 7 beats per minute) in the secretin group than the EGD-only group. There were mild elevations on the systolic and diastolic blood pressures. None of these changes were clinically significant. There were no complications reported during the anesthesia and procedures in the 2 groups. CONCLUSIONS: Secretin PFT is a safe procedure. It only slightly prolongs the total procedure and anesthesia time. There were no clinically significant changes in the vital parameters in the secretin group, and there were no adverse effects recorded.

Tricyclic farnesyl protein transferase inhibitors: crystallographic and calorimetric studies of structure-activity relationships.

Crystallographic and thermodynamic studies of farnesyl protein transferase (FPT) complexed with novel tricyclic inhibitors provide insights into the observed SAR for this unique class of nonpeptidic FPT inhibitors. The crystallographic structures reveal a binding pattern conserved across the mono-, di-, and trihalogen series. In the complexes, the tricycle spans the FPT active site cavity and interacts with both protein atoms and the isoprenoid portion of bound farnesyl diphosphate. An amide carbonyl, common to the tricyclic compounds described here, participates in a water-mediated hydrogen bond to the protein backbone. Ten high-resolution crystal structures of inhibitors complexed with FPT are reported. Included are crystallographic data for FPT complexed with SCH 66336, a compound currently undergoing clinical trials as an anticancer agent (SCH 66336, 4-[2-[4-(3,10-dibromo-8-chloro-6,11-dihydro-5H-benzo[5, 6]cyclohepta[1, 2-b]pyridin-11-yl)-1-piperidinyl]-2-oxoethyl]-1-piperidinecarbo xamide ). Thermodynamic binding parameters show favorable enthalpies of complex formation and small net entropic contributions as observed for 4-[2-[4-(3,10-dibromo-8-chloro-6,11-dihydro-11H-benzo[5, 6]cyclohepta[1, 2-b]pyridin-11-ylidene)-1-piperidinyl]-2-oxoethyl]pyridine N-oxide where DeltaH degrees bind = -12.5 kcal/mol and TDeltaS degrees bind = -1.5 kcal/mol.

Identification of pharmacokinetically stable 3, 10-dibromo-8-chlorobenzocycloheptapyridine farnesyl protein transferase inhibitors with potent enzyme and cellular activities.

Farnesyl protein transferase (FPT) is a promising target for the development of cancer chemotherapeutics because it is responsible for the farnesylation of oncogenic p21 Ras proteins which are found in nearly 30% of all human cancers and necessary for cellular development and growth. The recent discovery and progression to phase II clinical trials of trihalobenzocycloheptapyridine Sch-66336 as a potent inhibitor of FPT with oral, in vivo efficacy in mice have spawned extensive structure-activity relationship studies (SAR) of this class of compounds. Of the many trihalobenzocycloheptapyridine analogues prepared, we have identified several which inhibit FPT and cellular proliferation at single-digit nanomolar concentrations and which have good pharmacokinetic properties in mice.

(+)-4-[2-[4-(8-Chloro-3,10-dibromo-6,11-dihydro-5H-benzo[5, 6]cyclohepta[1,2-b]- pyridin-11(R)-yl)-1-piperidinyl]-2-oxo-ethyl]-1-piperidinecarboxamid e (SCH-66336): a very potent farnesyl protein transferase inhibitor as a novel antitumor agent.

We have previously shown that appropriate modification of the benzocycloheptapyridine tricyclic ring system can provide potent farnesyl protein transferase (FPT) inhibitors with good cellular activity. Our laboratories have also established that incorporation of either pyridinylacetyl N-oxide or 4-N-carboxamidopiperidinylacetyl moieties results in pharmacokinetically stable inhibitors that are orally efficacious in nude mice. We now demonstrate that further elaboration of the tricyclic ring system by introducing a bromine atom at the 7- or the 10-position of the 3-bromo-8-chlorotricyclic ring system provides compounds that have superior potency and selectivity in FPT inhibition. These compounds have good serum levels and half-lives when given orally to rodents and primates. In vitro and in vivo evaluation of a panel of these inhibitors has led to identification of 15 (SCH 66336) as a highly potent (IC50 = 1.9 nM) antitumor agent that is currently undergoing human clinical trials.

Frequency of restenosis after balloon pulmonary arterioplasty and its causes.

Restenosis has been described after balloon pulmonary arterioplasty (BPA), but litte is known about its frequency, settings, and time course. We undertook this study to (1) determine the incidence of restenosis after BPA, and (2) identify its potential determinants. We reviewed clinical data and measured pulmonary artery diameters from angiograms of 134 dilations on 75 patients (median 2.1 years, range 0.3 to 32) who had BPA from January 1990 to June 1998. Successful BPA was defined as a > or = 50% increase in predilation diameter, whereas restenosis was said to occur if there was a > or = 50% loss in initial diameter gain. The success rate after BPA by angiographic criteria was 64% (95% confidence interval 56% to 73%). Seventy-four percent of BPAs were successful by published standard criteria (angiographic criteria or > or = 20% change in right ventricular/aortic pressure). Baseline demographic variables and predilation parameters were not predictive of initial dilation success. Restenosis occurred in 35% (95% confidence interval 22% to 49%) of successfully dilated vessels. Only weight at follow-up (p = 0.02) was associated with an increased likelihood of restenosis. Predilation parameters, technical aspects of dilation, or immediate results of BPA were not predictive of restenosis. We therefore conclude that restenosis is unpredictable and more common after BPA than previously recognized.

Distribution of acute bowel inflammation determined by technetium-labeled white blood cells in children with inflammatory bowel disease.

Knowledge of the distribution of disease in patients with inflammatory bowel disease is important because it has diagnostic, prognostic, and therapeutic implications. We studied 215 patients with 99mTc-HMPAO-white blood cell scans, of whom 80 had Crohn's disease (CD), 34 had active ulcerative colitis (UC), and 31 were controls. In our 77 cases of active CD, uptake was seen exclusively in the small bowel in 18% of patients, only the large bowel in 44%, and both the large and small bowel in 38% of patients. Discontinuous colitis was seen in 63 of these patients. In the 29 cases of active UC, the uptake involved the entire colon in 50% of patients, extended farther than the sigmoid in 27% of patients, and was limited to the rectosigmoid in 23%. In the 29 cases of active UC, four of the scans incorrectly revealed discontinuous accumulation of 99mTc-HMPAO-WBC. In 31 controls, no significant colonic uptake was seen. Isolated small bowel involvement with CD is observed less frequently in children undergoing 99mTc-HMPAO-WBC scanning than in adults. In children, the segmental distribution of inflammation as depicted with 99mTc-HMPAO-WBC is similar to the radiologic distribution.

Characterization of late abdominal accumulation of 99Tcm-HMPAO leukocytes in a large population of children.

We retrospectively evaluated the incidence of late accumulation of 99Tcm-HMPAO leukocytes (99Tcm-WBC) in the right lower quadrant of a large population of children and characterized some predictive patterns that would enable differentiation of active inflammation from this late occasional accumulation of 99Tcm-WBC. We reviewed the charts of 211 children. The first group evaluated consisted of 79 controls: 30 normal children with no gastrointestinal disease, but who underwent 99Tcm-WBC scanning for other medical problems, and 49 children who had non-specific gastrointestinal (GI) complaints, but had no demonstrable inflammatory bowel disease by conventional diagnostic methods. The second group consisted of 132 children with inflammatory bowel disease: 80 children with Crohn's disease (CD), 34 with ulcerative colitis (UC) and 18 with indeterminate colitis (IC). Children were imaged at 30 min and 3 h. Fifteen (19%) of the 79 controls scanned showed accumulation of 99Tcm-WBC in the right lower quadrant at 3 h and none at 30 min. Of those 15, 8 were from the control population and 7 from the group with non-specific GI complaints and negative work-ups. There was no uptake in other segments of the bowel. The accumulation was faint, of lesser intensity than in the iliac wing, and diffuse, such that identification of a specific loop of involved bowel was not possible. Migration of the 99Tcm-WBC distal to the terminal ileum was demonstrated. The other 64 children in the control group showed no accumulation of 99Tcm-WBC at any time during their scans. All 79 scans were blindly interpreted as normal studies. There were no false-positive readings encountered in the 132 children with inflammatory bowel disease (80 CD, 34 UC, 18 IC) when the aforementioned characteristics of the late accumulation of 99Tcm were used to differentiate inflammation from this physiological excretion. In conclusion, the late accumulation of 99Tcm-WBC in the right lower quadrant is characterized by (1) accumulation at no less that 3 h, (2) no accumulation in other segments of the bowel, (3) faint accumulation of lesser intensity than in the iliac wing, (4) a diffuse accumulation pattern and (5) migration of the 99Tcm-WBC into the caecum and ascending colon over time. Recognition of this excretion pattern enables differentiation of active Crohn's disease of the small bowel from migration and accumulation of 99Tcm-WBC in the right lower quadrant of the abdomen.

Retrospective analysis of alternate-day prednisone maintenance therapy for Crohn's disease.

We reviewed the medical records of 98 children with Crohn's disease followed at Children's Hospital of Pittsburgh from 1983 to 1993 to evaluate the merits of alternate-day prednisone (AD) maintenance therapy once initial remission was achieved. Of the 98 children, 35 had adequate data recorded for eligibility to the study. Of these, 11 were in the AD group and 24 were in a group whose maintenance regimen did not include prednisone (NO). The dependent variables were frequency of flares and linear growth over time. AD therapy reduced mean symptomatic flares (0.23 +/- 0.1 vs 0.69 +/- 0.14 flares/patient/year; p = 0.04) over a 2-year follow-up period but did not delay significantly the onset of a flare after remission was achieved (16.5 +/- 3.4, vs 13.4 +/- 1.8 months; p = 0.4). Site of disease involvement had no impact on frequency of flares. Fewer patients in the AD group experienced flares, but this finding did not achieve statistical significance (4/11, 36%, vs 17/24, 71%; p = 0.07). Linear growth, measured in height percentile and growth velocity (cm/year), was not significantly reduced by the second year of either therapy. This small retrospective study suggests that AD prednisone therapy may be effective in reducing symptomatic flares in Crohn's patients without a resultant inhibition of linear growth.

Comparison of the sensitivity of early versus delayed imaging with Tc-99m HMPAO WBC in children with inflammatory bowel disease.

The difference in sensitivity of early imaging at 30 minutes after injection of Tc-99m HMPAO WBC versus delayed imaging at 2 or 3 hours for depiction of active inflammation in children with inflammatory bowel disease was established. The charts of 220 children who had early (30-minute) and delayed (2 or 3 hours) imaging performed for evaluation of inflammatory bowel disease were reviewed. There were 107 boys and 113 girls (average age, 12 years; median, 13 years). The bowel was divided into eight segments (with the total for all patients being 3,520) graded on a scale of 0 to 6 (with reference points in the iliac crest and liver). Any grade > or = 1 was abnormal. The uptake in each segment was summed. One hundred and twenty-two studies were abnormal (55%). The average uptake in the early images was 5.1 +/- 0.41 and that in the late images was 9.3 +/- 0.64. The Friedman nonparametric test of comparison of rank was significant at the 0.001 level. One hundred and five patients had abnormal studies at 30 minutes (88%). An additional 12% of patients had abnormal studies only on the late images. There were 245 abnormal segments at 30 minutes and 413 abnormal segments at 2 or 3 hours. When the uptake was analyzed segment by segment, 62 patients (52%) had abnormal segments at 30 minutes but also had additional abnormal segments at 3 hours. Sensitivity of Tc-99m HMPAO WBC imaging was significantly improved when late imaging was performed.

[Uroflowmetric nomogram in the adult population of Canary Islands]. / Nomograma uroflujométrico en la población adulta canaria.

In order to know the uroflowmetric values of our healthy population, a uroflowmetry was made to 214 healthy subjects of both sexes. 75% of our group of volunteers collected mictional volumes under 300 ml. with no differences either by age or sex. The corresponding nomograms, in the form of percentile, for peak and mean flow in both sexes, were created. We found a progressive increase of peak and mean flow values with regard to mictional volume. Time to peak flow is shorter in women than in men. Volume at peak flow represents under 50% of total mictional volume. No significant differences in the uroflowmetric data of our healthy population and those from Anglo-Saxon authors was found.

[Surgical treatment of laryngotracheal stenosis in childhood]. / Tratamiento quirúrgico de las estenosis laringotraqueales en la infancia.

Acquired or congenital laryngotracheal stenosis is uncommon in children although premature infants with respiratory distress syndrome (SDR) requiring ventilatory support with prolonged intubation are at great risk. The different treatments used in the past show high rates of morbidity and mortality. Following the technique described by Cotton in 1980, anterior cricoid slit procedure in the upper two tracheal rings has been used as a primary treatment on five patients since 1991, four by intrinsic stenosis and one by extrinsic. Extubation failed in four of them, checking trough bronchoscopy different grades of laryngotracheal stenosis and in the fifth due to respiratory distress, secondary to subcricoid stenosis. Anterior cricoid split procedure with intubation with conventional endotracheal tube (SET) or Montgomery tube (TTM) was performed on infants whose ages ranged from 4 to 18 months old (averaged 8 months). They were extubated between the 5th and 340th days after surgery. Two of them underwent complications: a skin-tracheal fistula and a paresis of the left vocal cord, the two are asymptomatic after four and eighteen months of the procedure. All patients discharged without signs of upper airway obstruction, except one who developed a granuloma which diminished with cortisone. Anterior cricoid split with prolonged intubation is a safe and useful technique for the treatment of laryngotracheal stenosis.

[Thrombophlebitis of the lateral sinuses. A difficult diagnostic case for nine otorhinolaryngologists]. / Tromboflebitis del seno lateral. Un difícil diagnóstico para los nuevos otorrinolaringólogos.

Since the advent of antibiotic era lateral sinus thrombophlebitis has become an scarce complication in otology. The clinical picture can present under several aspects, specially if given a course of antibiotics previously, which complicates the diagnose. We report a case recently treated and compare ours with the classic symptomatology quoted in the literature.

[Giant cholesteatoma of the external ear canal after myringoplasty]. / Colesteatoma gigante del conducto auditivo externo posmiringoplastia.

Cholesteatoma are specially localized in middle ear and mastoid process, although sometimes is the external ear canal which shows the disorder. Usually its a appearance is spontaneous. We report a rare case of gigantic cholesteatoma which origin was the previous otologic surgery done because of the inclusion of a bit of epithelial tissue inside the surgical incision. Similar outcomes justify periodical checking after ear surgery with outlining a tympanomeatal flap.

[Lateral isolated neurofibroma of the neck]. / Neurofibroma solitario del espacio laterocervical.

The neurofibroma (NF) of the neck is a neurogenic tumor seldom presented. Sometimes solitary, as the case reported, or within the context of von Recklinghausen's disease. When diagnosis is doubtful either the TAC, the RMN of the PAAF show its usefulness. However the ultimate diagnosis is made through the histologic exam of the removed lump, which is the elective treatment.

[A review of the management of orbital cellulitis]. / Revisión del manejo de las celulitis orbitarias.

Twenty cases of orbital cellulitis were presented requiring hospitalization. Of theses their clinical history, diagnostic criteria, treatment and evolution was revised. It was observed that it is an unusual complication of sinusal pathology of which the precocious hospitalization multidisciplinary treatment avoids the appearance of endocranial complication.

[Inflammatory pseudotumor of the lymph nodes. A case report]. / Seudotumor inflamatorio de ganglios linfáticos. A propósito de un caso.

Inflammatory pseudotumor of the lymph nodes is a little-known condition characterized mainly by cervical lymph node enlargement, hematological manifestations, and major constitutional symptoms in most patients. The diagnosis is histological, after surgical removal of an involved lymph node. Histologically, stromal proliferation and neovascularity are present, as well as lymphocytic infiltration. This disease is considered benign because of its tendency toward spontaneous resolution, even though symptoms are usually intense. A male patient presented cervical lymph node enlargement, constitutional syndrome, and hematological manifestations, including oscillating thrombocytopenia, leukopenia, and increased ESR. The diagnosis was inflammatory pseudotumor of the lymph nodes, a rare disease. The evolution is torpid but the prognosis is good. This disease should be considered in the differential diagnosis of tumors of the neck region.