The technique of Heller laparoscopic myotomy with associated Dor anterior fundoplication for the treatment of esophageal achalasia is described. This operation was performed on three patients with clinical, radiologic, and manometric diagnoses of achalasia. Complete relief of dysphagia and modifications of radiological and manometric patterns were achieved in all patients 1 month after surgery. Laparoscopic treatment of achalasia is technically feasible, reduces surgical trauma, and may be considered a valid alternative to open surgery.

Adult↗

PubMedDate not supplied

Relationship between retinal ischemia and cardiovascular autonomic damage in diabetes.

In order to investigate the relationship between ischemic diabetic retinopathy and cardiac autonomic dysfunction we studied 40 diabetic patients (mean age +/- SEM: 48 +/- 2 years). Retinopathy was evaluated by fluorescein angiography and patients were divided into three groups: a) with ischemic retinopathy (15 patients), b) with edematous retinopathy (13 patients) and c) without retinopathy (12 patients). Cardiac autonomic function was assessed by 4 tests based on cardiovascular reflexes (heart rate response to Valsalva maneuver and to deep breathing; systolic blood pressure fall after standing and diastolic blood pressure rise during handgrip) and by the cross-correlation test, a computerized technique for the analysis of respiratory sinus arrhythmia based on spectral analysis of electrocardiographic and respiratory signals. Abnormalities of cardiac autonomic tests were present in 26/40 patients (65%); considering the retinal angiographic classification, autonomic test abnormalities were found in 13/15 (86.6%) patients with ischemic retinopathy, in 7/13 (53.9%) patients with edematous retinopathy and in 6/12 (50%) patients without retinopathy. The prevalence of cardiac autonomic dysfunction was significantly higher (p less than 0.005) in the ischemic retinopathy group compared to the other groups. These results show a strong association between ischemic retinopathy and cardiac autonomic dysfunction.

Autonomic Nervous System↗

PubMedDate not supplied

Bedside diagnosis of cardiac autonomic damage by computerized analysis of heart rate-respiration relationship.

In this study we propose a method for the analysis of the relationship between heart rate changes and respiration as a possible diagnostic tool for cardiac autonomic damage. The method consists in recording R-R intervals and respiratory amplitude by a suitably equipped personal computer, and by evaluating the cross-correlation peak between the two signals. This mathematical function appeared to be more sensitive to the degree of concordance between the two signals, rather than their absolute amplitude. The cross-correlation appeared to be lower in diabetics with autonomic dysfunction, markedly decreased after injection of atropine (only in normals), slightly increased after propranolol. Hyperpnea increased the cross-correlation peak between 3-18 breaths/min in normals, but only at lower frequencies, if at all, in diabetic subjects with various degrees of autonomic dysfunction. The cross-correlation showed the best reproducibility among R-R change tests. These preliminary results suggest that this method may provide new information on autonomic integrity and a substantial advantage in terms of reproducibility.

Adult↗

PubMedDate not supplied

Metallic stents in benign biliary strictures: three-year follow-up.

Eighteen patients with recurrent benign biliary strictures (BBS) were selected for metallic stents placement because they failed to respond to percutaneous balloon dilatation. None were candidates for surgical corrections. We used "Z" single or double stents in 17 cases and a Wallstent in 1 case. After more than 3 years of follow-up (average period 37 months, range 30-41 months), 10 patients (55.5%) were asymptomatic without signs of bile stasis; 5 patients (27.7%) had recurrence of symptoms and were eventually retreated; and 3 patients (16.6%) died, 2 of obstructive jaundice and liver failure and 1 of metastatic gastric cancer. Recurrence was due to stent occlusion by tissue ingrowth in 3 cases, stent migration in 1 case, and an inflammatory lesion of the papilla of Vater in another case, with patency of the metallic stent. The overall patency rate, at 3-year follow-up was 68.7%. In our series, the main factor determining long-term patency of metallic stents has been reactive tissue ingrowth. Nevertheless, long-term results obtained with metallic stents in recurrent benign biliary strictures should be considered satisfactory. In selected patients, metallic stents may represent the only long-term treatment available for maintaining bile flow.

Adult↗

PubMedDate not supplied

Immobilization on chitosan of a thermophilic beta-glycosidase expressed in Saccharomyces cerevisiae.

A Sulfolobus solfataricus beta-glycosidase expressed in Saccharomyces cerevisiae (S beta gly) was immobilized on chitosan activated with glutaraldehyde. The yield of immobilization was evaluated as 80%. Compared to the free beta-glycosidase, the immobilized enzyme showed a similar pH optimum (pH = 7.0), the same increasing activity up to 80 degrees C, improved thermostability, and no inhibition by glucose. Functional studies pointed out that the kinetic constant values for both enzymes were comparable. A bioreactor, assembled with the immobilized S beta gly, was used for glucose production. The values of cellobiose conversion increased on increasing residence time in the bioreactor, following a nonlinear trend. However, the highest glucose production/min was obtained at a flow of 0.5 mL/min.

Chitin↗

PubMedDate not supplied

Effect of cytidine analogs on cell growth and differentiation on a human neuroblastoma line.

The cytidine analog 5-AZA-2'-deoxycytidine (5-AZA-CdR) has been demonstrated to induce cellular differentiation; on the other hand, induction of differentiation has been suggested as a possible form of therapy for leukemic cells. We have evaluated the possibility that the neuroblastoma malignant tumor growth could be controlled by treatment that promotes the differentiation of immature tumor cells. We have previously reported on differentiation of murine neuroblastoma cells (41A3) treated with 5-AZA-CdR. In this paper, we describe the effect of 5-AZA-CdR on human neuroblastoma cell line CHP-100. The drug-treated cells show some degree of differentiation, demonstrated by morphological and biochemical markers. A significant DNA hypomethylation and partial inhibition of DNA synthesis and cell proliferation is also observed. This effect is more stable than that caused by another cytidine analog, Cytosine-beta-D-Arabinofuranoside (ARA-C).

Acetylcholinesterase↗

PubMedDate not supplied

Nucleotide sequence, expression and transcriptional analysis of the Bifidobacterium longum MB 219 lacZ gene.

The gene encoding beta-galactosidase was isolated by functional complementation of Escherichia coli from Bifidobacterium longum MB219, which exhibited the highest activity among ten Bifidobacterium strains tested of the species B. longum, B. breve, B. adolescentis, B. indicum, B. animalis and B. cuniculi. The nucleotide sequence of the 5.0-kb fragment conferring the positive beta-galactosidase phenotype to E. coli revealed the presence of a lacZ-type gene encoding a 1023-amino-acid protein that was preceded by a ribosome binding site. A sequence showing 72% identity with the proline tRNA of Bacillus subtilis and a gene probably encoding the DNA-3-methyladenine glycosydase I were located downstream from the lacZ gene, after a gap of 30-50 unsequenced base pairs. By primer-extension analysis, the transcription start site of the lacZ gene was mapped 65 nt upstream from the start codon, and it enabled identification of the -10 region of the putative promoter. The nucleotide sequence of lacZ and its deduced amino acid sequence were compared with those of beta-galactosidase genes and enzymes from other microorganisms. High similarity was demonstrated between the B. longum beta-galactosidase and its counterparts in Lactobacillus delbruckii subsp. bulgaricus, Streptococcus salivarius subsp. thermophilus, E. coli, Clostridium acetobutylicum, Leuconostoc lactis, Klebsiella pneumoniae and Kluyveromyces marxianus var. lactis, all belonging to the LacZ family. The B. longum MB219 lacZ gene was cloned in Bifidobacterium and its expression was observed in strains with otherwise low levels of endogenous activity. The expression increased by factors of 1.5-50 and enabled those strains that do not grow on lactose to use this sugar as sole carbon source.

Base Sequence↗