Molecular and cytological characterization of ribosomal RNA genes in Chenopodium quinoa and Chenopodium berlandieri

The nucleolus organizer region (NOR) and 5S ribosomal RNA (rRNA) genes are valuable as chromosome landmarks and in evolutionary studies. The NOR intergenic spacers (IGS) and 5S rRNA nontranscribed spacers (NTS) were PCR-amplified and sequenced from 5 cultivars of the Andean grain crop quinoa (Chenopodium quinoa Willd., 2n = 4x = 36) and a related wild ancestor (C. berlandieri Moq. subsp. zschackei (Murr) A. Zobel, 2n = 4x = 36). Length heterogeneity observed in the IGS resulted from copy number difference in subrepeat elements, small re arrangements, and species-specific indels, though the general sequence composition of the 2 species was highly similar. Fifteen of the 41 sequence polymorphisms identified among the C. quinoa lines were synapomorphic and clearly differentiated the highland and lowland ecotypes. Analysis of the NTS sequences revealed 2 basic NTS sequence classes that likely originated from the 2 allopolyploid subgenomes of C. quinoa. Fluorescence in situ hybridization (FISH) analysis showed that C. quinoa possesses an interstitial and a terminal pair of 5S rRNA loci and only 1 pair of NOR, suggesting a reduction in the number of rRNA loci during the evolution of this species. C. berlandieri exhibited variation in both NOR and 5S rRNA loci without changes in ploidy.

[National survey on vitreo-retinal surgery and the management of rhegmatogenous retinal detachments in Spain. Project retina 2]

PURPOSE

To obtain information throughout Spain on the current management of vitreo-retinal surgical diseases, the number of ophthalmologists involved in retinal surgical diseases care, and the urgent management of retinal detachments.

METHODS

A 30 item questionnaire was sent by mail, on two separate occasions, to the heads of Ophthalmology Departments of 276 centers in Spain.

RESULTS

A total response rate of 48.2% was achieved, however the answers from private centers represented only 9.4% of the total so these were excluded from the analysis. The centers most likely to respond were those in Teaching Hospitals (TH) (52.3%). Of these, 64% of hospitals responded that, in the last year, they performed pars plana vitrectomies (PPV) and 70% performed more than 100 PPVs in the year. In all, 77% of the centers that performed PPVs had also performed them urgently. A total of 75% of hospitals indicated that they had ophthalmologists mainly dedicated to retinal diseases care, with a median of 2 specialists per center, with this representing 23% of their total staff. Retinal surgery was performed by general ophthalmologists in 11.5% of centres. Only 40.3% of hospitals audit their results (37.5% TH).

CONCLUSIONS

Despite the existence of a relatively low response rate, as well as some biases and methodological problems, data on the management of retinal surgical disease has been obtained for the first time at a national level. This data will facilitate later studies and must be taken into consideration in improving the planning and adequate management of these diseases in Spain.

Prevalence Data of Rickettsia slovaca and Other SFG Rickettsiae Species in Dermacentor marginatus in the Southeastern Iberian Peninsula

In southern Spain, Dermacentor marginatus ticks can be infected with several genospecies of spotted fever Group (SFG) Rickettsia. We developed a nested polymerase chain reaction assay by using a species-specific probe targeting the ompA gene to detect and differentiate between the two groups of rickettsiae previously described in D. marginatus. SFG rickettsia has been detected in 85.15% of ticks studied (26.7% of positives have been to R. slovaca, the causative agent of TIBOLA-DEBONEL, and 73.3% to SFG rickettsia closely related to strains RpA4-JL-02-DnS14-DnS28).

Value of serological testing for diagnosis of legionellosis in outbreak patients

Serum antibody detection tests and a urine antigen detection technique were compared in samples from 116 patients epidemiologically characterized as belonging to a legionellosis outbreak. Sera were tested by enzyme-linked immunosorbent assays (ELISAs) for immunoglobulin M (IgM) and IgG plus IgM and by immunofluorescent assays (IFAs) for IgG, IgM, IgA, and polyimmunoglobulin using commercial kits (Vircell); concentrated urines were tested with the Binax NOW Legionella test. ELISA for IgM, ELISA for IgG plus IgM, antigenuria detection, and IFA for IgM were able to diagnose 72.3%, 60.5%, 53.3%, and 51.4%, respectively, of patients. Antigenuria was present in 53.8% of first samples, ELISA detected IgM in 29.7%, ELISA detected IgG plus IgM in 7.9%, and IFA detected IgM in 3.9%. Ten antigenuria-negative first samples tested serologically positive, 9 of them to IgM by ELISA. Despite the single source of the samples included in the study, detection of IgM using a sensitive technique such as ELISA seems to be a suitable complement to antigenuria detection for the diagnosis of legionellosis.

PCR-DIG ELISA with biotinylated primers is unsuitable for use in whole blood samples from patients with brucellosis

In an attempt to avoid some of the inconveniences associated with conventional PCR, such as electrophoresis in ethidium bromide, we developed and analyzed the yield of a digoxigenin-based enzyme-linked immunosorbent PCR assay (PCR-DIG ELISA) for the detection of specific Brucella target DNA. During the DNA amplification process in healthy subjects and controls (Brucella abortus B-19) non-specific amplification of fragments was formed between genomic DNA and specific biotin-labeled primers. The labeled non-specific fragments bound to streptavidin-coated wells, saturating the solid phase streptavidin by biotin-streptavidin interaction. The formation of these non-specific PCR products was demonstrated by reduction in absorbance with hemin, a Taq polymerase inhibitor, and identified by use of a silver stained method which improves the sensitivity of nucleic acid visualization.

Hemoglobin Mass and Peak Oxygen Uptake in Untrained and Trained Female Altitude Residents

Total hemoglobin mass has not been systematically investigated in females at altitude. We measured this quantity (CO-rebreathing method) as well as peak oxygen uptake in 54 young women (age 22.5 +/- 0.6 SE years) with differing physical fitness living in Bogota (2600 m) and compared the results with those of 19 subjects from 964 m in Colombia and 75 subjects from 35 m in Germany. In spite of an increased hemoglobin concentration the hemoglobin mass was not changed in highlanders (means 9.0 to 9.5 g . kg (-1) in untrained subjects at all altitude levels). Endurance trained athletes, however, showed a rise in hemoglobin mass by 2 - 3 g . kg (-1) at all sites. Erythropoietin was little increased in Bogota; iron stores were within the normal range. Aerobic performance capacity was lower at high altitude than at sea level and remained so also after correction for the hypoxic deterioration in untrained and moderately trained subjects but not in athletes; possibly the cause was reduced daily physical activity in non-athletic Bogotanians compared to lowlanders. After exclusion of the factor V.O(2peak) by analysis of covariance a mean rise of 6.6 % in hemoglobin mass at 2600 m was calculated being smaller than in males (> 12 %). The attenuated increase of hemoglobin mass in female highlanders possibly results from stimulation of ventilation improving arterial oxygen saturation or from an increased hypoxia tolerance of cellular metabolism both caused by female sexual hormones.

Prevalence of intestinal metaplasia according to the length of the specialized columnar epithelium lining the distal esophagus in patients with gastroesophageal reflux

The diagnosis of Barrett's esophagus is based on the presence of intestinal metaplasia (IM) at the distal esophagus. The aim of this study was to determine the prevalence of IM in patients with symptoms of gastroesophageal reflux in whom endoscopically a segment of distal esophagus was covered by columnar epithelium (CE). In a prospective, descriptive and transversal study, 492 patients (33%) from 1480 patients with gastroesophageal reflux, in whom endoscopic evaluation demonstrated the presence of a short-segment CE measuring less than 3 cm or a long-segment CE measuring more than 3 cm, were evaluated. From each patient, several biopsy specimens were taken, which were stained with hematoxylin-eosin and Alcian blue pH 2.5. Out of 492 cases, 421 patients (86%) presented with a short-segment CE and 71 patients (14%) had a long-segment CE. Among these 71 cases, 38 had a 3-6 cm-length CE, 21 patients had a 6.1-10 cm-length CE and 12 patients had CE more than 10.1 cm in length. Endoscopic short-segment CE was six times more frequent than long-segment CE. The prevalence of IM was 35% among patients with short-segment CE and increased progressively according to the length of CE, being 100% in patients with > 10 cm in length. Therefore, true short-segment BE was three times more frequent during endoscopic studies than long-segment BE. Dysplasia in the metaplastic epithelium also increased parallel to the length of the CE. True BE (presence of IM at the columnar epithelium lining the distal esophagus), was present in 13.6% of all patients with symptoms of gastroesophageal reflux submitted to endoscopic evaluation. Short-segment BE is three times more frequent than long-segment BE, and endoscopic and bioptic evaluation is fundamental in all cases with gastroesophageal reflux who exhibit some segment of the distal esophagus lined by columnar epithelium, even if it is > or = 1 cm long.

Direct evidence that leukemic cells present HLA-associated immunogenic peptides derived from the BCR-ABL b3a2 fusion protein

The BCR-ABL oncogene is central in the pathogenesis of chronic myeloid leukemia (CML). Here, tandem nanospray mass spectrometry was used to demonstrate cell surface HLA-associated expression of the BCR-ABL peptide KQSSKALQR on class I-negative CML cells transfected with HLA-A*0301, and on primary CML cells from HLA-A3-positive patients. These patients mounted a cytotoxic T-lymphocyte response to KQSSKALQR that also killed autologous CML cells, and tetramer staining demonstrated the presence of circulating KQSSKALQR-specific T cells. The findings are the first demonstration that CML cells express HLA-associated leukemia-specific immunogenic peptides and provide a sound basis for immunization studies against BCR-ABL.

Hemoglobin mass and peak oxygen uptake in untrained and trained residents of moderate altitude

Blood composition, hemoglobin mass (CO rebreathing method) and VO2peak were measured in 15 untrained (UT-Bogotá) and 14 trained males (TR-Bogotá) living at 2600 m of altitude, and in 14 untrained lowlanders (UT-Berlin). [Hb] amounted to 15.3 + 0.2(SE) g/dl in UT-Berlin, 17.4 + 0.2 g/dl in UT-Bogotá and 16.0 + 0.2 g/dl in TR-Bogotá. Hb mass was significantly higher in UT-Bogotá (13.2 + 0.4 g/kg, P < 0.01) and in TR-Bogotá (14.7 + 0.5 g/kg, P < 0.001) than in UT-Berlin (11.7 + 0.2 g/kg). In TR-Bogotá also plasma volume was expanded. Erythropoietin concentrations in UT-Bogotá and TR-Bogotá were not significantly increased. There was a positive correlation between blood volume and VO2peak for the pooled values of all subjects, if the oxygen uptake of UT-Berlin was corrected for an ascent to 2600 m. For the Hb mass - VO2peak relation two groups are indicated pointing to two types of altitude acclimatization with different Hb mass increases but similar distribution of aerobic performance capacity. We suggest that different genetic properties in a population of mixed ethnic origin might play a role.

Late follow-up of polypoid lesions of the gallbladder smaller than 10 mm

OBJECTIVE

To determine the variation in number, size, and symptoms in patients with polypoid lesions of the gallbladder.

SUMMARY BACKGROUND DATA

A polypoid lesion is any elevated lesion of the gallbladder mucosa. Several studies have been reported in patients undergoing cholecystectomy, but little information exits regarding the natural history of these lesions in nonoperated patients.

METHODS

A total of 111 patients with ultrasound diagnosis of polypoid lesions smaller than 10 mm were followed up by clinical evaluation and ultrasonography. Twenty-seven patients underwent cholecystectomy.

RESULTS

There was no difference in terms of gender. Nearly 80% of the lesions were smaller than 5 mm; they were single in 74%. In nonoperated patients, 50% remained of similar size at the late follow-up, 26.5% increased in number and size, and 23.5% shrank or disappeared. Among the operated patients, 70% corresponded to cholesterol polyps. None of the patients developed symptoms of biliary disease or gallstones or adenocarcinoma.

CONCLUSIONS

Ultrasound is useful in the follow-up of patients with polypoid lesions of the gallbladder. Lesions smaller than 10 mm do not progress to malignancy or to development of stones, and none produced symptoms or complications of biliary disease.

[Pathological gastroesophageal reflux in patients with severe, morbid and hyper obesity]

BACKGROUND

Overweight can be a risk factor for pathological gastroesophageal reflux or hiatal hernia.

AIM

To study the prevalence of gastroesophageal reflux in patients with severe obesity.

PATIENTS AND METHODS

Sixty seven patients, 51 female, aged 17 to 56 years old with a body mass index over 35 kg/m2, were studied. An upper gastrointestinal endoscopy was performed in all, esophageal manometry was done in 32 and 24 h pH monitoring was done in 32 patients.

RESULTS

Seventy nine percent of patients complained of heartburn and 66% of regurgitation. In 16 patients, endoscopy was normal. An erosive esophagitis was found in 33 patients, a short columnar epithelium in 12 and a Barret esophagus with intestinal metaplasia in six. Normal endoscopic findings and erosive esophagitis were present with a higher frequency in women. No association between the degree of obesity and esophageal lesions was observed. Lower esophageal sphincter pressure and abdominal length were significantly higher in subjects with a body mass index over 50 compared to those with a body mass index between 35 and 39.9 kg/m2. No differences were observed in 24 h pH monitoring.

CONCLUSIONS

A high proportion of severely obese patients had symptoms and endoscopical findings of pathological gastroesophageal reflux.

Liver transplantation and hepatitis C virus. Results in a Spanish center since 1989

BACKGROUND/AIMS

Hepatitis C-related liver disease is the main indication for liver transplantation in many centers. Viral RNA remains after transplantation in almost 100% of the patients, and more recent reports show a graft hepatitis rate of about 90%. The progression of this hepatitis seems to be quicker than in the nontransplant setting.

METHODOLOGY

From June 1989 to October 2000, 197 adult patients had 213 for HCV-related liver disease at our institution. Basal immunosuppression consisted of a triple therapy with cyclosporine, azathioprine and steroids, or dual therapy with tacrolimus and steroids. None of the patients was treated with antivirals after liver transplantation.

RESULTS

Pure HCV-related cirrhosis was the indication for liver transplantation in 114 patients, another 14 with hepatocellular carcinoma, 8 associated metabolic diseases, 43 high alcohol intake, 4 hepatitis B, 5 cholestatic diseases, and 3 other diseases. Six patients out of the 197 transplanted in this period were already grafted before this time, and had their first retransplantation of the liver after 1989 (their first liver transplantation was done when HCV was not known). Sixteen additional retransplantation procedures were done in the period considered. Hepatitis was diagnosed in 84.3% of the grafts biopsied later than 90 days after liver transplantation (118/140), and in 92.9% if it was done after one year (92/99). Cirrhosis was diagnosed in 21 grafts at a mean time of 1004.7 days, 21.2% of the grafts biopsied after 1 year and 28.6% after 2 years. Nine grafts in 8 patients were diagnosed as fibrosing cholestatic hepatitis. Patient actuarial survival was 80.9%, 69.7%, 67.5% and 50.6% at 1, 3, 5 and 10 years. Liver failure and hepatoma recurrence were the cause of death in 42.4% of the patients. Actuarial graft survival was 75.2%, 64.9%, 63.5% and 48.6% at 1, 3, 5 and 10 years, and was significantly affected by Child stage (B vs. C, P = 0.004). When compared to 228 non-HCV- infected patients with chronic parenchymatous disease, these had an almost significantly better patient survival (P = 0.0577), but a nonsignificant difference in graft survival. Graft loss related to liver causes was 17.6% in HCV+ patients 14.6% in HCV- patients. Liver causes of death were 14.0% in HCV+ patients and 4.8% in HCV-patients (P = 0.002).

CONCLUSIONS

HCV infected liver transplantation recipients present very often graft hepatitis, which may progress to advanced stages in a quite short interval. Mid-term patient and graft survival is comparable to those of non-HCV recipients, but causes of death related directly to liver disease are more common in HCV+. This makes one think that long-term prognosis (more than 10 or 15 years) will be worse in HCV patients.

Phenotypic comparison of periodontal ligament cells in vivo and in vitro

The mammalian periodontal ligament contains heterogeneous populations of connective tissue cells, the precise function of which is poorly understood. Despite close proximity to bone and the application of high amplitude physical forces, cells in the periodontal ligament (PL) are capable of expressing regulatory factors that maintain PL width during adult life. The study of PL homeostasis and PL cell differentiation requires culture and phenotypic methods for precise characterization of PL cell populations, in particular those cells with an inherently osteogenic program. Currently it is unknown if cells cultured from the PL are phenotypically similar to the parental cells that are present in the tissues. We have compared the phenotype of cells in vivo with cells derived from the PL and expanded in vitro to assess the general validity of in vitro models for the study of phenotypic regulation in vivo. Rat PL cells were isolated by either scraping the root of the extracted first mandibular molars (Group A), or by scraping the alveolar socket following extraction of first mandibular molars (Group B), or by obtaining a mixture of cells after disaggregating a block of tissue consisting of first mandibular molar, PL and the surrounding alveolar bone (Group C). Cultured cells at confluence were fixed and immunostained for alpha-smooth muscle actin (alpha-SMA), osteopontin (OPN), alkaline phosphatase (AP), or bone sialoprotein (BSP). For in vivo assessments, frontal sections of rat first mandibular molar were immunostained for alpha-SMA, OPN, AP and BSP. We examined osteogenic differentiation of cultured PL cell cultures by bone nodule-forming assays. In vivo and at all examined sites, > 68% of PL cells were immunostained for AP; approximately 50% and approximately 51% for OPN and alpha-SMA (p = 0.3), respectively, while only approximately 8% were positively stained for BSP (p < 0.01). Analysis of cultured PL cells in Groups A, B and C showed 54%, 53%, and 56% positive staining for alpha-SMA respectively; 51%, 56%, 54% for OPN; 66%, 70%, 69% for AP and 2.2%, 1.4% and 2.8% for BSP. The mean percentage of PL cells in situ stained for the different markers was similar to that of cultured PL cells (Group A approximately Group B approximately Group C in situ for p > 0.2) except for BSP which was 3 to 4 fold higher in vitro (p < 0.01). PL cell cultures treated with dexamethasone showed mineralized tissue formation for all groups (A, B, C), but no mineralized tissue formation was detected in the absence of dexamethasone. As PL cells express quantitatively similar phenotypes in vitro and in vivo, we conclude that the in vitro models used here for assessment of PL cell differentiation appear to be appropriate and are independent of the cell sampling method. Further, dexamethasone-dependent progenitors are present both on the root and bone-related sides of the PL.

Prevalence of Barrett's esophagus by endoscopy and histologic studies: a prospective evaluation of 306 control subjects and 376 patients with symptoms of gastroesophageal reflux

The classic endoscopic diagnosis of a Barrett's esophagus (BE) is based on the finding of > or =3 cm, of distal esophagus covered by specialized columnar epithelium. However, currently, it is based on the finding of intestinal metaplasia (IM) at the squamous-columnar mucosal junction, independent of its extent. The aim of this study was to determine the prevalence of Barrett's esophagus by endoscopic and histological findings in control subjects and in patients with symptoms of gastroesophageal reflux (GER). Three hundred and six control subjects and 376 patients with symptoms of gastroesophageal reflux were included in this prospective study. Patients with Barrett's esophagus were classified in three groups as follows. 1. Intestinal metaplasia at the cardia. When endoscopy showed non-Barrett's esophagus, but histological intestinal metaplasia was found. 2. Short-segment Barrett's esophagus. When <3 cm, was covered with tongues or finger-like or creeping substitution of distal esophagus. 3. Long-segment Barrett's esophagus. When > 3 cm, of distal esophagus was covered by specialized columnar epithelium. Two biopsies at the antrum, four biopsies at the squamous-columnar junction and one or two at the distal esophagus were taken. In control subjects, 1.6% showed histological IM at the esophagogastric junction. In patients with GER without esophagitis or with erosive esophagitis, IM was found in 18% and 10.7% respectively. 'Short-segment' Barrett's esophagus was three times more frequent than 'long-segment' Barrett's esophagus. Patients with Barrett's esophagus were significantly older than the other groups. The presence of complications or erosions, peptic ulcer or stricture were significantly more frequent among patients with 'long-segment' Barrett's esophagus (p < 0.0001). The prevalence of dysplasia was similar in all groups of patients with Barrett's esophagus. Complications such as ulcers, stricture and dysplasia were exclusively seen among patients with BE, whereas non-Barrett's patients did not exhibit these complications. In control subjects, IM can be found in a low percentage of cases. Among patients with symptoms of GER, the classic endoscopic diagnosis of a Barrett's esophagus can underestimate this condition in 80% of the cases. Patients with intestinal metaplasia at the cardia already present 17% of the cases with low-grade dysplasia. In all patients with symptoms of GER, systematic biopsies at the squamous-columnar junction should be taken.

Comparison of clinical, endoscopic and functional findings in patients with intestinal metaplasia at the cardia, carditis and short-segment columnar epithelium of the distal esophagus with and without intestinal metaplasia

In recent years, the diagnosis of short segments of intestinal metaplasia lining the distal esophagus has increased. The aim of the present study was to determine the clinical, endoscopic, histologic and functional results in patients with intestinal metaplasia at the cardia (IMC), carditis and short-segment columnar epithelium (CE) lining the distal esophagus with and without intestinal metaplasia. Four groups were studied: 48 patients with carditis, 105 patients with IMC, 78 patients with short-segment CE (SSCE) without IM and 69 patients with short-segment CE with IM. All had clinical questionnaire, endoscopic and histological evaluation, manometric studies and measurements of acid and bilirubin exposition of the distal esophagus over 24 h. Patients without IM were found to be younger than those with IM. Erosive esophagitis was observed in similar proportions, but hiatal hernia was present in patients with SSCE with or without IM. Patients without IM had mainly cardial mucosa more than fundic mucosa. However, patients with IM had almost exclusively cardial mucosa. Low-grade dysplasia was observed only in patients with IM. Manometric evaluation demonstrated a structural defective lower esophageal sphincter in all groups. Acid and duodenal exposures of the distal esophagus over 24 h were significantly greater in patients with SSCE with IM. In the presence of pathologic gastroesophageal reflux (GER), there are several histological changes at the mucosa distal to the squamous columnar junction. The first metaplastic change is one from fundic to cardial mucosa and, when duodenal reflux occurs, a second metaplastic change to intestinal metaplasia from cardial mucosa occurs. Therefore, in all patients with symptoms of GER, biopsies specimens distal to the squamous columnar junction should be taken routinely.

Student attitudes toward lesbian, gay, and bisexual issues: analysis of self-talk categories

The purpose of this study was to (a) examine the utility of using the thought-listing technique to examine participants' attitudes toward lesbian, gay, and bisexual issues and (b) determine the effectiveness of two new training interventions (rational and experiential) that were designed using cognitive-experiential self-theory (Epstein, 1994). Fifty participants were randomly assigned to one of three treatment conditions (rational training, experiential training, control group). Participants completed a thought-listing technique before and after receiving one of the theoretically based training interventions. Three judges free sorted the 2,481 collected thoughts and identified and defined 25 thought categories. Three trained judges then placed 2,426 (98%) of the thoughts into these categories. Results indicated that different categories of responses (cognitive, affective, behavioral) emerged among the individuals which provided four distinct profiles of how people thought about the topic of homosexuality. Furthermore, chi-square analyses revealed that the experiential group had changes in their thoughts after receiving the workshop. Findings are discussed and suggestions for future research are provided.

[Results of cholecystectomy realized 10 years ago]

BACKGROUND

The "post cholecystectomy" syndrome comprises a series of vague symptoms referred by patients subjected to this surgical procedure. These symptoms are unspecific and their association with the operation is dubious.

AIM

To assess the frequency of digestive symptoms among patients subjected to a cholecystectomy ten years ago.

PATIENTS AND METHODS

One hundred patients subjected to a cholecystectomy between 1987 and 1990, were contacted by mail. They were invited to a clinical interview and to an abdominal ultrasound examination.

RESULTS

Two invited patients had died of an acute myocardial infarction. Therefore, 98 patients (78 women), aged 30 to 85 years old, were assessed. Seventy two percent had diverse dyspeptic symptoms, 90% had no food intolerance and 94% had gained weight after the operation. Ninety six percent was satisfied with the surgical results, 3% had severe symptoms due to gastroesophageal reflux or depression. One patient had a residual choledocholithiasis and refused any treatment.

CONCLUSIONS

Cholecystectomy is well tolerated and has good long term results.

How the free limbs are used by elite high jumpers in generating vertical velocity

The aim of this study was to quantify how elite high jumpers used their free limbs in a competitive high jump and to estimate the contribution that these made to vertical take-off velocity. This was achieved by analysing the competitive performances of six elite male high jumpers using 3D motion analysis and assessing limb function using the relative momentum method. The mean peak relative momentum of the arm nearest to the bar at take-off was 9.4 kg m s(-1), while that of the arm furthest away from the bar was 11.3 kg m s(-1) and these did not differ significantly. The free (lead) leg reached a mean peak relative momentum of 20.9 kg m s(-1). At touch-down the free leg had a large positive relative momentum that was offset by the negative relative momentum of the arms, although their combined value still remained positive. The mean combined free limbs' relative momentum at touch-down was 13.8 kg m s(-1) and reached a peak of 37.6 kg m s(-1). The difference between these two values amounted to 7.1 % of whole-body momentum, which was judged to be the amount by which the free limbs contributed to performance. The arms had a greater influence on performance than had the lead leg. This was because the lead leg increased its relative momentum little during the contact period while the arms had an initial negative value that increased markedly after touch-down. The compressive force exerted by the motion of the free limbs, estimated by the change in the combined free limbs' relative momentum, reached a mean peak of 366 N and was greatest at 37% of the contact period. It was concluded that to maximize the contribution the free limbs can make to performance, given the restraints imposed on technique by other performance requirements, the arms should have a vigorous downward motion at touch-down to make the most use of the high (but little changing) relative momentum of the lead leg.

Number and size of stones in patients with asymptomatic and symptomatic gallstones and gallbladder carcinoma: a prospective study of 592 cases

The development of gallbladder carcinoma has been correlated with the presence of a single large gallstone in two retrospective studies. The objective of the present study was to determine the number and size of gallstones in patients with gallbladder carcinoma compared to asymptomatic and symptomatic female patients with gallstones. The following three groups of patients were included in this prospective trial: (A) 78 asymptomatic patients with gallstones; (B) 365 symptomatic patients with gallstones; and (C) 149 patients with gallbladder carcinoma. At the end of the operation, the resected gallbladder was opened and the number of stones counted. The maximum size of the stones was determined using calipers. Patients with gallbladder carcinoma were significantly older than patients in the other two groups (P <0.001). In the group with asymptomatic gallstones, there were significantly more patients with one single stone, whereas in the group with gallbladder carcinoma there were significantly more patients with multiple stones (more than 11; P <0.01). Patients with gallbladder carcinoma had significantly larger stones, regardless of the number of stones present (P <0.001). We postulate that the increase in the number and size of the stones among patients with gallbladder carcinoma could simply be an effect of aging or it could be a reflection of the long-term presence of stones in the gallbladder rather than some particular chemical or physical influence.

[Prevalence of cardial or fundic mucosa and Helicobacter pylori in the squamous-columnar mucosa in patients with chronic patological gastroesophageal reflux without intestinal metaplasia comparated with controls]

BACKGROUND

The mucosa distal to the endoscopic mucosal change zone can have easily diagnosed early alterations, in patients with chronic gastroesophageal reflux.

AIM

To determine the type of mucosa existent in the zone distal to the squamous-columnar junction in patients with chronic gastroesophageal reflux without intestinal metaplasia.

PATIENTS AND METHODS

One hundred thirty four controls and 208 patients with chronic gastroesophageal reflux lasting two years were studied. Forty three of these patients had a normal endoscopy, 54 had an erosive esophagitis and 111 had a short columnar epithelium covering the distal esophagus, without intestinal metaplasia. In all subjects, four biopsies were obtained from a zone distal to the squamous-columnar junction and two from the distal gastric antrum.

RESULTS

In 59% of control subjects, fundic mucosa was present in the zone distal to the squamous-columnar junction. Cardial mucosa was present in the rest. In patient with chronic gastroesophageal reflux, cardial mucosa was predominant. Helicobacter pylorii infection decreased along with increasing extension of cardial mucosa covering the distal esophagus.

CONCLUSIONS

In patients with chronic gastroesophageal reflux there is a metaplasia of fundic mucosa towards cardial mucosa. On the other hand, Helicobacter pylorii infection decreases gradually.