Bayesian methods for the conformational classification of eight-membered rings

Two methods for the classification of eight-membered rings based on a Bayesian analysis are presented. The two methods share the same probabilistic model for the measurement of torsion angles, but while the first method uses the canonical forms of cyclooctane and, given an empirical sequence of eight torsion angles, yields the probability that the associated structure corresponds to each of the ten canonical conformations, the second method does not assume previous knowledge of existing conformations and yields a clustering classification of a data set, allowing new conformations to be detected. Both methods have been tested using the conformational classification of Csp3 eight-membered rings described in the literature. The methods have also been employed to classify the solid-state conformation in Csp3 eight-membered rings using data retrieved from an updated version of the Cambridge Structural Database (CSD).

Clinico-pathological analysis of the cutaneous lesions of a patient with type I pseudohypoaldosteronism

The autosomal recessive form of type I pseudohypoaldosteronism (PHA-I) is an unusual disorder characterized by aldosterone resistance at the target organs, which leads to an excessive loss of sodium chloride through urine, sweat and saliva, among other secretions. Such a high concentration of salt in the sweat during the depletive crises directly causes inflammation and damage in the eccrine structures, with cutaneous lesions similar to those appearing in miliaria rubra. We report an autosomal recessive PHA-I in a 4-year-old girl, with cutaneous lesions mimicking miliaria rubra, that improved after treatment with astringent solutions and avoidance of profuse sweating.

[Cutaneous hemangiomas and vascular malformations and associated pathology (Pascual-Castroviejo type II syndrome). Study of 41 patients]

AIM

To describe the clinical, diagnostic and therapeutic features of this angiomatous neurocutaneous syndrome, which is the most frequent one, and to report a personal series of 41 patients.

PATIENTS AND METHODS

Forty one patients--31 females and 10 males--were studied during childhood and then, several patients were followed during many years, which allowed us to learn about the evolution of the abnormalities. The cutaneous lesions were classified as hemangiomas in 30 patients (73%) and as vascular malformations in 11 patients (27%).

RESULTS

A cerebellar anomaly (unilateral hemispheric hypoplasia and Dandy-Walker malformation) was seen in 13 patients (31.5%) cerebral cortical dysplasia in 4 patients (10%), aortic arch coarctation in 6 patients (15%), and congenital cardiopathy in 5 patients (12%). The most frequent abnormalities were intracranial and/or extracranial vascular malformations. Persistence of the trigeminal artery was observed in 7 patients (17%), absence or severe hypoplasia of an internal carotid artery in 13 patients (32%), absence of a vertebral artery in 7 patients (17%), hypoplasia of intracranial arteries in 6 patients (15%) and aneurysmal enlargement of carotid or vertebral arteries in 5 patients (12%). Also were observed 4 patients (10%) with intracranial hemangioma, 2 (5%) with hemangioma in mediastinum, and 3 (7.5%) with intestinal hemangioma, all of which disappeared during the first years of life. Aneurysmal enlargement of the carotid and vertebral arteries and intracranial branches also disappeared after a process of progressive narrowing of the arterial lumen that caused complete obstruction of these arteries. At the same time the cutaneous hemangioma regressed. During this process, collateral vascularization through branches of the external carotid artery and of the non-affected branches of the contralateral intracranial arteries developed.

CONCLUSION

This neurocutaneous syndrome is the most frequent one and it is associated with several types of vascular and non-vascular abnormalities which can involve any organ of the body. Internal and external hemangiomas and hemangiomatous lesions progress and tend to regress concomitantly.

High Prevalence of Ulcerative Posthitis in Rasa Aragonesa Rams Associated with a Legume-rich Diet

This study describes an outbreak of ulcerative posthitis that eventually affected 76 of 80 of rams in a flock of Rasa Aragonesa sheep on a legume-rich diet. Lesions were confined to the prepuce and varied from mild hyperaemia to ulcerations. Corynebacterium renale was isolated from the lesions. Treatment of an initial group of 17 was based on a change of diet and topical treatment with Veterin Banedif with prednisolone once a day for 15 days and was successful. Lesions in this group were completely resolved after 15 days. The relationship between a legume-rich diet, ruminal alkalosis, elevated urine pH and posthitis is discussed.

Potato tuber isoapyrases: substrate specificity, affinity labeling, and proteolytic susceptibility

Apyrase/ATP-diphosphohydrolase hydrolyzes di- and triphosphorylated nucleosides in the presence of a bivalent ion with sequential release of orthophosphate. We performed studies of substrate specificity on homogeneous isoapyrases from two potato tuber clonal varieties: Desiree (low ATPase/ADPase ratio) and Pimpernel (high ATPase/ADPase ratio) by measuring the kinetic parameters K(m) and k(cat) on deoxyribonucleotides and fluorescent analogues of ATP and ADP. Both isoapyrases showed a broad specificity towards dATP, dGTP, dTTP, dCTP, thio-dATP, fluorescent nucleotides (MANT-; TNP-; ethene-derivatives of ATP and ADP). The hydrolytic activity on the triphosphorylated compounds was always higher for the Pimpernel apyrase. Modifications either on the base or the ribose moieties did not increase K(m) values, suggesting that the introduction of large groups (MANT- and TNP-) in the ribose does not produce steric hindrance on substrate binding. However, the presence of these bulky groups caused, in general, a reduction in k(cat), indicating an important effect on the catalytic step. Substantial differences were observed between potato apyrases and enzymes from various animal tissues, concerning affinity labeling with azido-nucleotides and FSBA (5'-p-fluorosulfonylbenzoyl adenosine). PLP-nucleotide derivatives were unable to produce inactivation of potato apyrase. The lack of sensitivity of both potato enzymes towards these nucleotide analogues rules out the proximity or adequate orientation of sulfhydryl, hydroxyl or amino-groups to the modifying groups. Both apyrases were different in the proteolytic susceptibility towards trypsin, chymotrypsin and Glu-C.

Phenotype characterization and natural history of spondylothoracic dysplasia syndrome: a series of 27 new cases

Spondylothoracic dysplasia (STD, MIM#277300) is an autosomal recessive disorder with high prevalence in the Puerto Rican population. It is generally regarded as a lethal condition. Since Jarcho and Levin described it in 1938, it has been referred to as spondylocostal dysplasia, costovertebral dysplasia, Jarcho-Levin syndrome and STD. We have prospectively characterized 27 patients with STD by detailed physical examination, pedigree analysis, thoracic CT scans, and pulmonary function tests (PFTs). Diagnoses were established using spinal radiographs and 3-D reconstructive CT scans to demonstrate fusion of the ribs at the costo-vertebral junction with a fan-like (crab-like) configuration of the thorax. Vertebral segmentation and formation defects were seen throughout the spine with a decrease in the number of vertebral bodies. Characteristic vertebral shape consisted of a decrease in antero-posterior diameter and an increase in lateral length, giving the vertebra a sickle shape. Eight out of 18 prospectively follow patients died within the first 6 months of life, a 44% mortality rate. Cause of death was respiratory insufficiency secondary to pneumonia and pulmonary restriction. This is an important finding since the vast majority of STD syndrome patients cited in the medical literature have died in the newborn and early childhood periods. Age of the remaining patients ranged from 4 months to 47 years. This represents the largest collection of patients with STD reported and it has allowed us to determine a detailed phenotype. Given 56% survival at 6 months, we show that STD is not a lethal syndrome.

Experimental evidence of coupling between sheared-flow development and an increase in the level of turbulence in the TJ-II stellarator

The link between the development of sheared flows and the structure of turbulence has been investigated in the plasma boundary region of the TJ-II stellarator. The development of the naturally occurring velocity shear layer requires a minimum plasma density. Near this critical density, the level of edge turbulent transport and the turbulent kinetic energy significantly increases in the plasma edge. The resulting shearing rate in the phase velocity of fluctuations is comparable to the one required to trigger a transition to improved confinement regimes with reduction of edge turbulence, suggesting that spontaneous sheared flows and fluctuations keep themselves near marginal stability. These findings provide the experimental evidence of coupling between sheared flows development and increasing in the level of edge turbulence. The experimental results are consistent with the expectations of second-order transition models of turbulence-driven sheared flows.

Does phosphorylation of eukaryotic elongation factor eEF2 regulate protein synthesis in ischemic preconditioning?

Ischemia/reperfusion-associated translation inhibition in the hippocampus is attenuated significantly at reinitiation and elongation steps by ischemic preconditioning (Burda et al. [2003] Neurochem. Res. 28:1237-1243). To address potential regulation of the elongation step by changes in eukaryotic elongation factor 2 (eEF2) phosphorylation with and without acquired ischemic tolerance (IT), Wistar rats were preconditioned by 5-min sublethal ischemia and 2 days later, 30-min lethal ischemia was induced. Given the important role that oxidative stress plays in the ischemic process, eEF2 phosphorylation was also studied in a model of oxidative stress in vitro. Three blocks of our results support a lack of correlation between eEF2 phosphorylation status and protein synthesis rate. First, eEF2 was dephosphorylated significantly (activated) after transient cerebral ischemia in rats with and without IT or H2O2-treated cells; however, protein synthesis was significantly inhibited under these three conditions. Second, after 30-min reperfusion, the protein synthesis rate was maintained below control levels in cortex and hippocampus of rats without IT. Eukaryotic EF2 phosphorylated levels were notably low only in the cortex, whereas levels in the hippocampus were close to that of sham controls. In rats with IT, protein synthesis was virtually restored in both brain regions, but phosphorylated eEF2 levels were even higher than in rats without IT. Third, after 4-hr reperfusion, the protein synthesis rate in cortex and hippocampus was observed to be below sham control values in rats with and without IT. Conversely, phosphorylated eEF2 levels were below sham control in rats with IT and reached sham control values in rats without IT.

Analysis of genetic variability of Indian isolates of Hepatitis C virus

The degree of genetic variability among Hepatitis C virus strains circulating in India is currently unknown. In order to get insight into this matter, sequence data obtained from the 5' non coding region from 8 patients from New Delhi were compared with sequences from 16 HCV isolates from different geographic locations of India. The phylogenetic analysis of most prevalent genotypes revealed the presence of novel HCV variants in type 1 strains.

Candidiasis sistémica y tratamiento con infliximab

The use of infliximab in patients with luminal or fistulizing Crohn's disease refractory to medical treatment (steroids and immunomodulatory drugs) is increasingly widespread. Although the incidence of serious infections in patients undergoing infliximab treatment is not higher than that of controls, systemic fungal infections in patients treated with this antibody have been anecdotally described. We report a case of systemic candidiasis in a patient with refractory Crohn's disease who was treated with infliximab associated with corticosteroids and azathioprine and discuss the role that infliximab could have played in the development of this complication.

[Retroperitoneoscopy: minimally invasive renal surgery]

OBJECTIVE

Retroperitoneal laparoscopy is well known as a surgical technique in adult patients. Its use in pediatric surgery is still-recent but, because of the good results, retroperitoncoscopy indications are getting more acceptance and widening indications. The aim of this work is to analyze our initial experience in retroperitoneal laparoscopy procedures in urological diseases at our centre.

PATIENTS AND METHODS

From July 2001 to February 2002 retroperitoneal laparoscopy has been used in 6 patients aged 6 months to 14 years. Surgical indications were: pyelolithotomy (lithiasis non-subsidiary to extracorporeal shock wave lithotripsy (n = 1); nephrectomy ofmulticystic dysplastic kidney (n = 4); and nephrectomy of atrophicpelvic kidney (n = 1).

RESULTS

Mean operative time in nephrectomy has been 102 minutes, and 230 minutes in conservative surgery. All 5 patients nephrectomized were discharged 24 hours after operation with no postoperatory incidences. The patient operated on for pyelolithiasis (in which a external drainageand a pyelouretheral stent (pig-tail) was placed) remained one week until he could be discharged without drainage. The pig-tail stent was thrown out spontaneously three weeks later through the urethra. Follow up demonstrated no stenosis in this case and no complications in nephrectomy patients.

CONCLUSION

Retroperitoneal laparoscopy is effective and safe in renal surgery and surpasses transperitoneal laparoscopy because its safety in reconstructive surgery avoiding urine leakage risk into the abdomen.

Alcoholism in 274 patients with panic disorder in Spain, one of the main producers of wine worldwide

BACKGROUND

Though panic disorder (PD) and alcoholism have been found in epidemiologic studies to often co-occur, the influence of cultural factors on the order of onset of the disorders has not been frequently addressed.

METHODS

A sample of 274 patients with PD was assessed and compared according to the presence of alcohol use disorder (AUD) (alcohol abuse or dependence), employing several clinical scales.

RESULTS

A total of 26 subjects were diagnosed from AUD. In 73.1% of patients, onset of alcohol use was previous to PD onset. PD subjects with AUD were found to have an earlier age at PD onset. They were more likely to be males, to have a family history of alcoholism, to abuse other drugs and to experience a more severe PD (more attacks in the last month, higher scores in anticipatory anxiety).

CONCLUSIONS

Patients with PD and alcoholism may represent a distinct clinical subgroup. Our finding of an uncommon order of onset for both disorders may reflect cultural influences.

CLINICAL IMPLICATIONS

(i)The study of panic disorder patients with comorbid alcoholism may help to better characterize this subgroup of patients. (ii) Patterns of alcohol use and the order of onset of both disorders may be influenced by cultural factors, with important practical implications. (iii) Patients with panic disorder and alcoholism may represent a distinct clinical subgroup, with an earlier age at panic disorder onset and greater clinical severity of anxiety.

LIMITATIONS

(i) Our results refer to a clinical sample, which may not be representative of the general population. (ii) Alcoholic patients with a history of other drug abuse or dependence were not excluded. (iii) Owing to the small sample size, patients with alcohol dependence and with alcohol abuse were not separated.

Matrix metalloproteinase profile in patients with Creuztfeldt-Jakob disease

Preliminary findings suggest that abnormalities in matrix metalloproteinase (MMP) activity may be found in the cerebrospinal fluid (CSF) of patients with Creutzfeldt-Jakob disease (CJD). In this study of 16 subjects with CJD and 16 age-, and sex-matched controls, we determined the presence of MMP-2 and MMP-9 in their active and proenzyme forms, the relative levels of MMP-3 and four inhibitors of MMP activity (TIMP-1, TIMP-2, TIMP-3 and TIMP-4), and the concentration of 4-3-3 protein. The methodology used involved zymography and immunological techniques. The results indicate that, compared with controls, CJD patients have a significantly higher positive frequency of pro-MMP-9 and of the active form of MMP-2, along with significantly higher levels of TIMP-1 and TIMP-2, classical inhibitors of MMP-9 and MMP-2, respectively. We also found a positive correlation between 14-3-3 protein concentration and that of TIMP-1 and TIMP-2 levels (correlation coefficients of 0.793 and 0.798, respectively). These results suggest that abnormalities in MMP and TIMP profiles may be helpful in the biochemical characterisation of CJD.

Hepatitis C virus phylogeny: a useful clinical tool

In order to type 45 recent isolates of Hepatitis C virus (HCV) originating from four different geographic regions of the world, we performed phylogenetic analysis of a 192 nucleotides (nts) long sequence from the 5'non-coding region (5'-NCR) of the virus genome and compared them with 55 HCV isolates/strains of known type. The results of this study showed that phylogenetic studies can assign an HCV isolate to the correct type in 100% and to the correct subtype in 98%. A comparison ofthis method with other methods using commercial kits revealed that it is appropriate for clinical use and is cost effective.

Emboli in bulls killed in Spanish traditional bullfighting

The finding of brain tissue fragments in blood and lungs of cattle stunned in slaughterhouses has raised concerns about food safety in the context of the bovine spongiform encephalopathy epidemic. In the present study, the possible occurrence of brain tissue emboli in animals killed in traditional Spanish bullfighting was investigated. Thorough histological analysis of multiple possible target organs was carried out in 434 bulls. No evidence of brain tissue embolism was obtained, but emboli from diverse sources were detected in pulmonary and hepatic tissue of a significant number of animals. These emboli seem to have been caused by the use of a long sword, which extensively disrupts intra-thoracic and intra-abdominal organs and vascular structures.

Restoration of peristalsis in the esophagus of a patient diagnosed of achalasia

We report the case of a patient with dysphagia in whom a clinical and manometric follow-up was carried out. We initially observed a motor disorder of the esophageal spasm type. During manometric follow-up a progression to vigorous achalasia was observed. The patient was treated with pneumatic dilation, which obtained a good response to treatment. In manometries performed after treatment we observed a return of peristalsis in the distal esophageal body. Early treatment and short evolution of disease may allow peristalsis to recover in these cases. Peristalsis recovery casts new doubts on achalasia etiology.

Analysis of genetic heterogeneity of hepatitis C viruses in Central America reveals a novel genetic lineage. Brief report

Hepatitis C virus (HCV) has high genomic variability and at least six different types have been reported. The genotypes distribution is currently unknown among HCV strains circulating in Central America. In order to study the degree of genetic variability of strains isolated in Costa Rica, sequence data obtained from the 5' non coding region from 7 patients from Costa Rica were compared with published sequences from 57 strains of all types. The phylogenetic analysis revealed the existence of type 1 strains of a novel genetic lineage, recently described for some South American countries, and indicates an increasing diversification of HCV.

Malaria vectors in Bioko Island (Equatorial Guinea): PCR determination of the members of Anopheles gambiae Giles complex (Diptera: Culicidae) and pyrethroid knockdown resistance (kdr) in An. gambiae sensu stricto

Anopheles gambiae sensu lato Giles, 1902 and Anophelesfunestus Giles, 1900 are the main malaria vectors on the island of Bioko (Equatorial Guinea). This study was carried out to determine: a) members of the An. gambiae complex that may be present on the island of Bioko and, b) the sensitivity of An. gambiae sensu stricto to pyrethroids. The analysis by PCR detected the presence of An. gambiae s.s. as the major vector of the complex and the "forest chromosomal form" was demonstrated by cytogenetic analysis. The presence of Anopheles melas in the southwest, north and southeast of the island justifies its study as a vector. The molecular characterization of pyrethroid knockdown resistance (kdr) showed that the populations of An. gambiae s.s. were sensitive and no mutations were found. This fact justifies the implementation on a large scale of pyrethroid-impregnated bednets within the framework of the Malaria Control Program of Equatorial Guinea.

The initial inositol 1,4,5-trisphosphate response induced by histamine is strongly amplified by Ca(2+) release from internal stores in smooth muscle

We have studied the Ca(2+)-dependence and wortmannin-sensitivity of the initial inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) response induced by activation of either histamine or muscarinic receptors in smooth muscle from guinea pig urinary bladder. Activation of H(1) receptors with histamine (100 microM) produced a significant elevation in Ins(1,4,5)P(3) levels with only 5s stimulation and in the presence of external Ca(2+). However, this response was abolished fully by either the prolonged absence of external Ca(2+) or the depletion of internal Ca(2+) stores with thapsigargin (100nM) or ryanodine (10 microM). In contrast, the same conditions only slightly reduced the initial Ins(1,4,5)P(3) response induced by carbachol. The prolonged incubation of smooth muscle in 10 microM wortmannin to inhibit type III PI 4-kinase abolished both the early histamine-evoked Ins(1,4,5)P(3) and Ca(2+) responses. Conversely, wortmannin did not alter Ca(2+) release induced by carbachol, despite a partial reduction of its Ins(1,4,5)P(3) response. Collectively, these data indicate that the detectable histamine-induced increase in Ins(1,4,5)P(3) is more the consequence of Ca(2+) release from internal stores than a direct activation of phospholipase C by H(1) receptors. In addition, the effect of wortmannin implies the existence of a Ca(2+)-dependent amplification loop for the histamine-induced Ins(1,4,5)P(3) response in smooth muscle.

Experimental inoculation of conventional pigs with porcine reproductive and respiratory syndrome virus and porcine circovirus 2

Postweaning multisystemic wasting syndrome (PMWS) is a disease of nursery and fattening pigs characterized by growth retardation, paleness of the skin, dyspnea, and increased mortality rates. Porcine circovirus 2 (PCV2) has been demonstrated to be the cause of PMWS. However, other factors are needed for full development of the syndrome, and porcine reproductive and respiratory syndrome virus (PRRSV) infection has been suggested to be one of them. Twenty-four conventional 5-week-old pigs were distributed in four groups: control (n = 5), PRRSV inoculated (n = 5), PCV2 inoculated (n = 7), and PRRSV and PCV2 inoculated (n = 7). The two groups inoculated with PRRSV showed growth retardation. Pigs inoculated with both PRRSV and PCV2 had increased rectal temperature. One of these pigs developed wasting, had severe respiratory distress, and died. The most important microscopic lesion in pigs inoculated with PCV2 was lymphocyte depletion with histiocytic infiltration of the lymphoid organs, more severe and in a wider range of tissues in doubly inoculated pigs. Interstitial pneumonia was observed in the three inoculated groups. PCV2 nucleic acid was found by in situ hybridization in larger amounts and in a wider range of lymphoid tissues in PRRSV- and PCV2-inoculated than in PCV2-inoculated pigs. TaqMan PCR was performed to quantify the PCV2 loads in serum during the experiment. PCV2 loads were higher in doubly inoculated pigs than in pigs inoculated with PCV2 alone. These findings indicate that severe disease can be reproduced in conventional 5-week-old pigs by inoculation of PRRSV and PCV2. Moreover, these results support the hypothesis that PRRSV infection enhances PCV2 replication.