Clinical features, therapeutic choice and response by phototype in psoriasis: analysis of the French PsoBioTeq cohort

BACKGROUND

Little is known about phototype and the response to systemic treatment in psoriasis.

OBJECTIVES

To assess the characteristics of psoriasis, the therapeutic choice and its efficacy according to phototype.

METHODS

We included patients from the PsoBioTeq cohort initiating a first biologic. Patients were classified according to their phototype. The evaluation included disease characteristics, choice of the initial biologic and therapeutic response at 12 months based on 90% improvement from baseline in Psoriasis Area and Severity Index (PASI 90) and Dermatology Life Quality Index (DLQI) 0/1.

RESULTS

Of the 1400 patients included, 423 (30.2%), 904 (64.6%) and 73 (5.2%) were in the phototype I-II, III-IV and V-VI groups, respectively. The V-VI group had a higher initial DLQI, and more frequently initiated ustekinumab. Patients in the V-VI group maintained the initial biologic prescribed as did the other phototype groups, even though the proportion of patients reaching PASI 90 and DLQI 0/1 at 12 months was lower in this group than the other groups.

CONCLUSIONS

Patient phototype seems associated with quality of life and choice of the initial biologic in psoriasis. The phototype V-VI group less frequently switched treatments than did the other groups when the response was not efficient.

Management of perforated diverticulitis with generalized peritonitis. A multidisciplinary review and position paper

Perforated diverticulitis is an emergent clinical condition and its management is challenging and still debated. The aim of this position paper was to critically review the available evidence on the management of perforated diverticulitis and generalized peritonitis in order to provide evidence-based suggestions for a management strategy. Four Italian scientific societies (SICCR, SICUT, SIRM, AIGO), selected experts who identified 5 clinically relevant topics in the management of perforated diverticulitis with generalized peritonitis that would benefit from a multidisciplinary review. The following 5 issues were tackled: 1) Criteria to decide between conservative and surgical treatment in case of perforated diverticulitis with peritonitis; 2) Criteria or scoring system to choose the most appropriate surgical option when diffuse peritonitis is confirmed 3); The appropriate surgical procedure in hemodynamically stable or stabilized patients with diffuse peritonitis; 4) The appropriate surgical procedure for patients with generalized peritonitis and septic shock and 5) Optimal medical therapy in patients with generalized peritonitis from diverticular perforation before and after surgery. In perforated diverticulitis surgery is indicated in case of diffuse peritonitis or failure of conservative management and the decision to operate is not based on the presence of extraluminal air. If diffuse peritonitis is confirmed the choice of surgical technique is based on intraoperative findings and the presence or risk of severe septic shock. Further prognostic factors to consider are physiological derangement, age, comorbidities, and immune status. In hemodynamically stable patients, emergency laparoscopy has benefits over open surgery. Options include resection and anastomosis, Hartmann’s procedure or laparoscopic lavage. In generalized peritonitis with septic shock, an open surgical approach is preferred. Non-restorative resection and/or damage control surgery appear to be the only viable options, depending on the severity of hemodynamic instability. Multidisciplinary medical management should be applied with the main aims of controlling infection, relieving postoperative pain and preventing and/or treating postoperative ileus. In conclusion, the complexity and diversity of patients with diverticular perforation and diffuse peritonitis requires a personalized strategy, involving a thorough classification of physiological derangement, staging of intra-abdominal infection and choice of the most appropriate surgical procedure.

Survey on the CRISPR arrays in Lactobacillus helveticus genomes

Lactobacillus helveticus is a homofermentative thermophilic lactic acid bacteria that is mainly used in the manufacture of Swiss type and long-ripened Italian hard cheeses. In this study, the presence of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) were analysed in 25 L. helveticus genomes and identified in 23 of these genomes. A total of 40 CRISPR loci were identified and classified into five main families based on CRISPR repeats: Ldbu1, Lsal1, Lhel1, Lhel2 and a new repeat family named Lhel3. Spacers had a size between 30 and 40 bp whereas repeats have an average size of 30 bp, with three longer repeats. The analysis displayed the presence of conserved spacers in 23 of the 40 CRISPR loci. A geographical distribution of L. helveticus isolates with similar CRISPR spacer array profiles were not observed. Based on the presence of the signature protein Cas3, all CRISPR loci belonged to Type I. This analysis demonstrated a great CRISPR array variability within L. helveticus, which could be a useful tool for genotypic strain differentiation. A next step will be to understand the possible role of CRISPR/Cas system for the resistance of L. helveticus to phage infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Lactobacillus helveticus, a lactic acid bacteria species widely used as starter culture in the dairy industry has recently also gained importance as health-promoting culture in probiotic and nutraceutical food products. The CRISPR/Cas system, a well-known molecular mechanism that provides adaptive immunity against exogenous genetic elements such as bacteriophages and plasmids in bacteria, was recently found in this species. In this study, we investigated the presence and genetic heterogeneity of CRISPR loci in 25 L. helveticus genomes. The results presented here represent an important step on the way to manage phage resistance, plasmid uptake and genome editing in this species.

Men and women with Down syndrome exhibit different kinematic (but not spatio-temporal) gait patterns

BACKGROUND

Gait phenotypes are well documented in people with Down syndrome (pwDS), but sex-related differences are still unexplored. This study investigated the existence of possible differences in spatio-temporal and kinematic parameters of gait between men and women with DS using quantitative three-dimensional gait analysis.

METHODS

Gait patterns of 117 pwDS (53 F, 64 M) who underwent a computerised gait analysis from 2002 to 2017 were retrospectively analysed to obtain spatio-temporal gait parameters and kinematics in the sagittal plane at hip, knee and ankle joints, as well as foot progression.

RESULTS

Overall, when considered as a single group, the gait patterns found for pwDS confirmed the findings of previous studies. However, when analysed by sex, our data revealed that women with DS exhibit a larger hip flexion at late stance (42% to 54% of the gait cycle) and reduced knee flexion at the beginning of the swing phase (61% to 69% of the gait cycle). In contrast, men are characterised by larger foot extra-rotation angles through most of the stance phase (from 0% to 55% of the gait cycle) and at the end of the swing phase (92% to 99% of the gait cycle). No differences between men and women with DS were found concerning ankle dorsi- plantar-flexion or in all spatio-temporal parameters normalised by individuals' anthropometry, excluding cadence (higher in women).

CONCLUSIONS

The findings of the present study highlight the need to investigate gait dysfunctions in pwDS by taking their sex into consideration. Such an approach may be useful not only in gaining a better understanding of the pathophysiology of gait disturbances associated with DS but also in supporting a better orientation of rehabilitative treatments.

Reconstructive techniques for revision and limb salvage surgery in persons with haemophilia

Haemophilia is an inherited haemorrhagic disease characterized by the lack of coagulative factors associated nowadays mostly to musculoskeletal complications, particularly severe secondary arthritis in specific joints. Recurrent traumatic or spontaneous joint bleeding, induce severe arthropathy at a young age that can be treated only by joint replacement. Total knee or hip arthroplasty in young subjects may fail earlier due to wear or infections and in the haemophilic population, this means bone loss, pseudo tumours and the need of revision or even limb salvage surgery. Modern modular implants and the use of bone graft enriched by tissue engineering techniques such as a concentration of autologous mesenchymal cells or PRP may be helpful to compensate all bone loss and anatomic alterations due to failures of orthopaedic implants. The authors present their experience with this type of surgery and their biological approach to these challenging cases.

Genomic diversity and immunomodulatory activity of Lactobacillus plantarum isolated from dairy products

In this study, we aimed to investigate some functional characteristics and the immunomodulatory properties of three strains of Lactobacillus plantarum of dairy origin which, in a previous screening, showed to be candidate probiotics. Genome sequencing and comparative genomics, which confirmed the presence of genes involved in folate and riboflavin production and in the immune response of dendritic cells (DCs), prompted us to investigate the ability of the three strains to accumulate the two vitamins and their immunomodulation properties. The ability of the three strains to release antioxidant components in milk was also investigated. Small amounts of folate and riboflavin were produced by the three strains, while they showed a good antioxidant capacity in milk with FRAP method. The immune response experiments well correlated with the presence of candidate genes influencing in DCs cytokine response to L. plantarum. Specifically, the amounts of secreted cytokins by DCs after stimulation with cells of Lp790, Lp813 and Lp998 resulted pro-inflammatory whereas stimulation with culture supernatants (postbiotics) inhibited the release of interleukin (IL)-12p70 and increased the release of the anti-inflammatory IL-10 cytokine. This study adds further evidence on the importance of L. plantarum in human health. Understanding how probiotics (or postbiotics) work in preclinical models can allow a rational choice of the different strains for clinical and/or commercial use.

Realization of a high voltage generator by series connection of floating modules

A high voltage generator built by a series connection of 100 kV modules was produced. The series connection feasibility is ensured by the inherent floating character of each module which is wireless powered by high efficiency photovoltaic cells illuminated by a laser system. Each module is equipped with a control and monitoring board allowing excellent stabilization of the high voltage output. The performance of the system in terms of reliability, stability, and efficiency was evaluated. In particular using a three module setup, we achieved a maximum voltage of 234 kV with stability better than 0.1%.

Laparoscopic adhesiolysis: consensus conference guidelines

AIM

Laparoscopic adhesiolysis has been demonstrated to be technically feasible in small bowel obstruction and carries advantages in terms of post-surgical course. The increasing dissemination of laparoscopic surgery in the emergency setting and the lack of concrete evidence in the literature have called for a consensus conference to draw recommendations for clinical practice.

METHODS

A literature search was used to outline the evidence, and a consensus conference was held between experts in the field. A survey of international experts added expertise to the debate. A public jury of surgeons discussed and validated the statements, and the entire process was reviewed by three external experts.

RESULTS

Recommendations concern the diagnostic evaluation, the timing of the operation, the selection of patients, the induction of the pneumoperitoneum, the removal of the cause of obstructions, the criteria for conversion, the use of adhesion-preventing agents, the need for high-technology dissection instruments and behaviour in the case of misdiagnosed hernia or the need for bowel resection.

CONCLUSION

Evidence of this kind of surgery is scanty because of the absence of randomized controlled trials. Nevertheless laparoscopic skills in emergency are widespread. The recommendations given with the consensus process might be a useful tool in the hands of surgeons.

Lysogeny in Lactobacillus delbrueckii strains and characterization of two new temperate prolate-headed bacteriophages

AIMS

Frequency of lysogeny in Lactobacillus delbrueckii strains (from commercial and natural starters) and preliminary characterization of temperate bacteriophages isolated from them.

METHODS AND RESULTS

Induction of strains (a total of 16) was made using mitomycin C (MC) (0.5 mug ml(-1)). For 37% of the MC-treated supernatants, it was possible to detect phage particles or presence of killing activity, but only two active bacteriophages were isolated. The two temperate phages isolated were prolate-headed phages which belonged to group c of Lact. delbrueckii bacteriophages classification. Different DNA restriction patterns were obtained for each phage, while the structural protein profiles and packaging sites were identical. Distinctive one-step growth curves were exhibited by each phage. An influence of calcium ions was observed for their lysis in broth but not on the adsorption levels.

CONCLUSIONS

Our study showed that lysogeny is also present in Lact. delbrueckii strains, including commercial strains.

SIGNIFICANCE AND IMPACT OF THE STUDY

Commercial strains could be lysogenic and this fact has a great practical importance since they could contribute to the dissemination of active-phage particles in industrial environments.

Persistent dysphagia after laparoscopic fundoplication for gastro-esophageal reflux disease

Persistent postoperative dysphagia is a potentially severe complication of fundoplication for gastroesophageal reflux disease (GERD). The aim of this retrospective study was to analyze our experience of laparoscopic fundoplication for GERD in 276 consecutive patients, to determine the frequency of postoperative dysphagia and assess treatments and outcomes. There was no relation between preoperative dysphagia, present in 24 patients (8.7%), and postoperative DeMeester grade 2 or 3 dysphagia, present in 25 patients (9.1%). Ten (3.6%) patients had clinically significant postoperative dysphagia, eight (2.9%) underwent esophageal dilation, with symptom improvement in five. Four (1.4%) of our patients (two with failed dilation) and 11 patients receiving antireflux surgery elsewhere, underwent re-operation for persistent dysphagia 12 months (median) after the first operation. DeMeester grade 0 or 1 dysphagia was obtained in 10/13 evaluable patients. Our experience is fully consistent with that of the recent literature. Redo surgery is necessary in only a small fraction of operated patients with GERD with good probability of resolving the dysphagia. Best outcomes are obtained when an anatomical cause of the dysphagia is documented preoperatively.

Spread and variability of the integrase gene in Lactobacillus delbrueckii ssp. lactis strains and phages isolated from whey starter cultures

AIMS

To determine the presence, diffusion and variability of the integrase (int) gene in Lactobacillus delbrueckii ssp. lactis isolated from natural whey starters used for the production of Italian hard cheeses.

METHODS AND RESULTS

A PCR-based protocol aimed to amplify an internal fragment of the int gene was optimized taking into account phage genome sequences available from public databases. Thirty-seven of the 39 strains tested showed the presence of the putative int gene. Southern blot hybridization experiments confirmed data obtained by PCR. The presence of the putative int gene was observed also in 20 of 23 Lact. delbrueckii ssp. lactis lytic phages isolated from the same starter cultures used to isolate strains. Phylogenetic analysis of partial int gene revealed a high similarity both within and between strain- and phage-derived sequences. Sixty per cent of the int-positive strains resulted inducible with mitomycin C, and two of them released active phage particles.

CONCLUSIONS

Our preliminary findings seem to suggest that an important number of Lact. delbrueckii ssp. lactis strains associated with the whey starters are lysogenic.

SIGNIFICANCE AND IMPACT OF THE STUDY

Further contribution to obtain a clearer picture of the complex relationship between thermophilic lactic acid bacteria phage and host in whey starters for Italian, hard-cooked cheeses.

Effects of HEMA on type I collagen protein in human gingival fibroblasts

The cytotoxicity of dental composites has been attributed to the release of residual monomers from polymerized adhesive systems due to degradation processes or the incomplete polymerization of materials. 2-Hydroxyethyl methacrylate (HEMA) is one of the major components released from dental adhesives. Cytotoxic effects due to high concentrations of HEMA have already been investigated, but the influence of minor toxic concentrations on specific proteins such as type I collagen has not been studied in depth. The objective of this project was to study the effect of minor toxic concentrations of HEMA on human gingival fibroblasts (HGFs), investigating modification in cell morphology, cell viability, and the influence on type I collagen protein. Primary lines of human gingival fibroblasts were exposed to 3 mmol/L HEMA for different periods of time (24 h, 72 h, 96 h). The cell vitality was determined by MTT assay, and high-resolution scanning electron microscopy analysis was performed to evaluate differences in cell morphology before and after treatment. The presence and localization of type I collagen was determined by immunofluorescence in HGFs treated with HEMA for the same period of time. The vitality of the cells decreased after 72 h of exposure. The HGFs grown in monolayer and observed by field emission in-lens scanning electron microscopy demonstrated a preserved surface morphology after 24 h of treatment, while they showed an altered morphology after 96 h of treatment. Immunofluorescence demonstrated a reduction of type I collagen due to HEMA exposure after 96 h. From these results, we conclude that low concentrations of HEMA can significantly alter the morphology of human gingival fibroblasts and interfere with the presence of type I collagen protein.

Diaphragmatic acute massive herniation after laparoscopic gastroplasty for esophagectomy

Minimally invasive techniques are increasingly being used for oesophagectomy. Diaphragmatic hernia is a rare complication of gastroplasty in open surgery. One of the advantages of the laparoscopic technique, the lack of peritoneal adhesions, may lead to an increased rate of this complication. We report two cases of diaphragmatic acute massive herniation after laparoscopic gastroplasty for esophagectomy out of a series of 44 laparoscopic gastroplasties performed over 33 months. We discuss some technical aspects related to its occurrence. Prevention should include a limited crural division and fixation of the gastric tube to the diaphragmatic crura at primary surgery.

Evaluation of bacterial communities belonging to natural whey starters for Grana Padano cheese by length heterogeneity-PCR

AIMS

To detect bacteria present in controlled dairy ecosystems with defined composition by length-heterogeneity (LH)-PCR. LH-PCR allows to distinguish different organisms on the basis of natural variations in the length of 16S rRNA gene sequences.

METHODS AND RESULTS

LH-PCR was applied to depict population structure of the lactic acid bacteria (LAB) species recoverable from Grana Padano cheese whey starters. Typical bacterial species present in the LAB community were evidenced and well discriminated. Small differences in species composition, e.g. the frequent finding of Streptococcus thermophilus and the constant presence of thermophilic lactobacilli (Lactobacillus helveticus, Lact. delbrueckii subsp. lactis/bulgaricus and Lact. fermentum) were reliably highlighted. Specificity of LH-PCR was confirmed by species-specific PCR from total DNA of the cultures.

CONCLUSIONS

LH-PCR is a useful tool to monitor microbial composition and population dynamics in dairy starter cultures. When present, non-dominant bacterial species present in the whey starters, such as Strep. thermophilus, can easily be visualized and characterized without isolating and cultivating single strains. A similar approach can be applied to more complex dairy ecosystems such as milk or cheese curd.

SIGNIFICANCE AND IMPACT OF THE STUDY

Community members and differences in population structure of controlled dairy ecosystems such as whey starters for hard cheeses can be evaluated and compared in a relative easy, fast, reliable and highly reproducible way.

Pre-operative endoscopic ultrasonography can optimise the management of patients undergoing laparoscopic cholecystectomy with abnormal liver function tests as the sole risk factor for choledocholithiasis: a prospective study

BACKGROUND

Pre-operative endosonography has been proposed as a cost-effective procedure in the management of patients who undergo laparoscopic cholecystectomy having an intermediate risk of common bile duct stones. We prospectively evaluated the impact of pre-operative endosonography on the management of patients facing laparoscopic cholecystectomy with abnormal liver function tests as the sole risk factor for choledocolithiasis.

METHODS

Among 587 consecutive patients scheduled for laparoscopic cholecystectomy, 47 (8%) patients having one or more abnormal liver function tests but a normal appearance of common bile duct at abdominal ultrasound, underwent pre-operative endosonography. In patients with endosonography-detected common bile duct stones, a pre-operative endoscopic retrograde cholangiography was performed, or an intra-operative endoscopic retrograde cholangiography was scheduled. In all endosonography-negative patients, an intra-operative trans-cystic cholangiography was performed.

RESULTS

Endosonography detected common bile duct stones in nine patients (19%) but only in five of them stones were radiologically confirmed (PPV 0.55). Endosonography-detected stones were confirmed in four of four (100%) patients in whom cholangiography was performed within 1 week, but only in one of five (20%) patients in whom radiology was further delayed (P < 0.05). In three of four cases (75%), stones detected at endosonography but not confirmed at X-rays, were smaller than 2.0 mm. Among 38 patients with negative endosonography, common bile duct stones were found in two patients (NPV 0.95), whereas unplanned endoscopic stone extraction was needed only in one patient (NPV 0.97).

CONCLUSIONS

Pre-operative endosonography can spare unnecessary pre-operative endoscopic retrograde cholangiography as well as inappropriate scheduling of intra-operative endoscopic retrograde cholangiography in patients undergoing laparoscopic cholecystectomy with abnormal liver function tests. To maximise the impact of endosonography on the management of these patients, the procedure should be performed immediately before laparoscopic cholecystectomy.

Kinematic control of walking

The planar law of inter-segmental co-ordination we described may emerge from the coupling of neural oscillators between each other and with limb mechanical oscillators. Muscle contraction intervenes at variable times to re-excite the intrinsic oscillations of the system when energy is lost. The hypothesis that a law of coordinative control results from a minimal active tuning of the passive inertial and viscoelastic coupling among limb segments is congruent with the idea that movement has evolved according to minimum energy criteria (1, 8). It is known that multi-segment motion of mammals locomotion is controlled by a network of coupled oscillators (CPGs, see 18, 33, 37). Flexible combination of unit oscillators gives rise to different forms of locomotion. Inter-oscillator coupling can be modified by changing the synaptic strength (or polarity) of the relative spinal connections. As a result, unit oscillators can be coupled in phase, out of phase, or with a variable phase, giving rise to different behaviors, such as speed increments or reversal of gait direction (from forward to backward). Supra-spinal centers may drive or modulate functional sets of coordinating interneurons to generate different walking modes (or gaits). Although it is often assumed that CPGs control patterns of muscle activity, an equally plausible hypothesis is that they control patterns of limb segment motion instead (22). According to this kinematic view, each unit oscillator would directly control a limb segment, alternately generating forward and backward oscillations of the segment. Inter-segmental coordination would be achieved by coupling unit oscillators with a variable phase. Inter-segmental kinematic phase plays the role of global control variable previously postulated for the network of central oscillators. In fact, inter-segmental phase shifts systematically with increasing speed both in man (4) and cat (38). Because this phase-shift is correlated with the net mechanical power output over a gait cycle (3, 4), phase control could be used for limiting the overall energy expenditure with increasing speed (22). Adaptation to different walking conditions, such as changes in body posture, body weight unloading and backward walk, also involves inter-segmental phase tuning, as does the maturation of limb kinematics in toddlers.

Laparoscopic treatment of epiphrenic diverticula

BACKGROUND AND PURPOSE

Epiphrenic diverticula are a rare disease probably caused by long-standing impairment of esophageal motor activity. Symptomatic disease, which may worsen clinically during follow-up even to severe symptoms, is usually considered an indication for surgical treatment. Surgery for epiphrenic diverticula consists of diverticulectomy, which traditionally is performed through a left thoracotomy; a myotomy and partial fundoplication are generally included in order to treat the underlying motor disorder and to prevent or correct reflux. The same principles of surgical treatment can be achieved through the laparoscopic transhiatal approach. The aim of this paper is to describe the technique and the results of laparoscopic diverticulectomy combined with esophageal myotomy and antireflux wrap to treat epiphrenic diverticula of the esophagus.

PATIENTS AND METHODS

From January 1994 through May 2001, 11 patients underwent laparoscopic transhiatal diverticulectomy, esophageal myotomy, and partial fundoplication at our institution.

RESULTS

In all patients, the operation was completed through the minimally invasive access. The postoperative course was complicated in one patient (9%), who had a leak from the staple line, which was repaired through a thoracotomy. At follow-up, this patient had persistence of a small pouch at the diverticuletomy site. However, he was asymptomatic. All other patients were free of symptoms and without recurrence.

CONCLUSION

Laparoscopy offers good access to the distal esophagus and the inferior mediastinum. Removal of the diverticulum, treatment of the motor disorder, and prevention of postoperative reflux can all be obtained through this approach. The immediate postoperative and long-term results are satisfactory.

Mutations of the phenylalanine hydroxylase (PAH) gene in Brazilian patients with phenylketonuria

In the present study, 115 Brazilian families with phenylketonuria (PKU), mainly from the Southeast of the country, were studied using three laboratory methods (DGGE, SSCP, and sequencing). All 13 exons of the PAH gene were analyzed, including the splicing sites and the promoter region. We identified 50 distinct mutations and characterized 91% of the mutant alleles. The five most prevalent mutations of the 50 mutations identified (50% of the PKU alleles) were IVS10nt-11G-->A (17.4%), followed by R261Q (12.2%), V388M (9.1%), R252W (6.5%), and R270K (4.8%). The other mutations were rare. The mutation spectrum included 10 novel mutations (IVS5nt-54A-->G, IVS6nt17G-->T, E205A, F240S, K274E, I318T, L321L, C357G, IVS11nt17G-->A, and S411X). To characterize the origin and distribution of the PAH alleles we determined the association between the detected mutations and the PCR/RFLP haplotypes and VNTR alleles located on the PAH gene. For those patients whose mutant alleles were detected, we calculated the correlation with pretreatment phenylalanine levels, thus establishing a genotype/phenotype correlation. The present results confirm the marked heterogeneity observed at the PAH locus and contribute to the understanding of the distribution and frequency of PKU mutations in the Brazilian population.

Interactions between posture and locomotion: motor patterns in humans walking with bent posture versus erect posture

Human erect locomotion is unique among living primates. Evolution selected specific biomechanical features that make human locomotion mechanically efficient. These features are matched by the motor patterns generated in the CNS. What happens when humans walk with bent postures? Are normal motor patterns of erect locomotion maintained or completely reorganized? Five healthy volunteers walked straight and forward at different speeds in three different postures (regular, knee-flexed, and knee- and trunk-flexed) while their motion, ground reaction forces, and electromyographic (EMG) activity were recorded. The three postures imply large differences in the position of the center of body mass relative to the body segments. The elevation angles of the trunk, pelvis, and lower limb segments relative to the vertical in the sagittal plane, the ground reaction forces and the rectified EMGs were analyzed over the gait cycle. The waveforms of the elevation angles along the gait cycle remained essentially unchanged irrespective of the adopted postures. The first two harmonics of these kinematic waveforms explain >95% of their variance. The phase shift but not the amplitude ratio between the first harmonic of the elevation angle waveforms of adjacent pairs was affected systematically by changes in posture. Thigh, shank, and foot angles covaried close to a plane in all conditions, but the plane orientation was systematically different in bent versus erect locomotion. This was explained by the changes in the temporal coupling among the three segments. For walking speeds >1 m s(-1), the plane orientation of bent locomotion indicates a much lower mechanical efficiency relative to erect locomotion. Ground reaction forces differed prominently in bent versus erect posture displaying characteristics intermediate between those typical of walking and those of running. Mean EMG activity was greater in bent postures for all recorded muscles independent of the functional role. The waveforms of the muscle activities and muscle synergies also were affected by the adopted posture. We conclude that maintaining bent postures does not interfere either with the generation of segmental kinematic waveforms or with the planar constraint of intersegmental covariation. These characteristics are maintained at the expense of adjustments in kinetic parameters, muscle synergies and the temporal coupling among the oscillating body segments. We argue that an integrated control of gait and posture is made possible because these two motor functions share some common principles of spatial organization.

Viewer-centered and body-centered frames of reference in direct visuomotor transformations

It has been hypothesized that the end-point position of reaching may be specified in an egocentric frame of reference. In most previous studies, however, reaching was toward a memorized target, rather than an actual target. Thus, the role played by sensorimotor transformation could not be disassociated from the role played by storage in short-term memory. In the present study the direct process of sensorimotor transformation was investigated in reaching toward continuously visible targets that need not be stored in memory. A virtual reality system was used to present visual targets in different three-dimensional (3D) locations in two different tasks, one with visual feedback of the hand and arm position (Seen Hand) and the other without such feedback (Unseen Hand). In the Seen Hand task, the axes of maximum variability and of maximum contraction converge toward the mid-point between the eyes. In the Unseen Hand task only the maximum contraction correlates with the sight-line and the axes of maximum variability are not viewer-centered but rotate anti-clockwise around the body and the effector arm during the move from the right to the left workspace. The bulk of findings from these and previous experiments support the hypothesis of a two-stage process, with a gradual transformation from viewer-centered to body-centered and arm-centered coordinates. Retinal, extra-retinal and arm-related signals appear to be progressively combined in superior and inferior parietal areas, giving rise to egocentric representations of the end-point position of reaching.

Motor Patterns in Walking

Despite the fact that locomotion may differ widely in mammals, common principles of kinematic control are at work. These reflect common mechanical and neural constraints. The former are related to the need to maintain balance and to limit energy expenditure. The latter are related to the organization of the central pattern-generating networks.

Basal ganglia and gait control: apomorphine administration and internal pallidum stimulation in Parkinson's disease

Gait coordination was analyzed (four-camera 100 Hz ELITE system) in two groups of idiopathic Parkinson disease (PD) patients. Five patients underwent continuous infusion of apomorphine and were recorded in two different sessions (APO OFF and APO ON) in the same day. Three patients with a previous chronic electrode implantation in both internal globi pallidi (GPi) were recorded in the same experimental session with the electrodes on and off (STIM ON and STIM OFF). The orientation of both the trunk and the lower-limb segments was described with respect to the vertical in the sagittal plane. Lower-limb inter-segmental coordination was evaluated by analyzing the co-variation between thigh, shank, and foot elevation angles by means of orthogonal planar regression. At least 30 gait cycles per experimental condition were processed. We found that the trunk was bent forward in STIM OFF, whereas it was better aligned with the vertical in STIM ON in both PD groups. The legs never fully extended during the gait cycle in STIM OFF, whereas they extended before heel strike in STIM ON. The multisegmental coordination of the lower limb changed almost in parallel with the changes in trunk orientation. In STIM OFF, both the shape and the spatial orientation of the planar gait loops (thigh angle vs. shank angle vs. foot angle) differed from those of physiological locomotion, whereas in STIM ON the gait loop tended to resume features closer to the control. Switching the electrodes on and off in patients with GPi electrodes resulted in quasi-parallel changes of the trunk inclination and of the planar gait loop. The bulk of the data suggest that the basal-ganglia circuitry may be relevant in locomotion by providing an appropriate spatio-temporal framework for the control of posture and movement in a gravity-based body-centered frame of reference. Pallido-thalamic and/or pallido-mesencephalic pathways may influence the timing of the inter-segmental coordination for gait.

The frequency of 844ins68 mutation in the cystathionine beta-synthase gene is not increased in patients with venous thrombosis

BACKGROUND AND OBJECTIVES

A frequent mutation in the cystathionine beta-synthase (CBS) gene (844ins68, a 68-bp insertion in the coding region of exon 8) was recently discovered. In the present study we investigated this mutation as a candidate risk factor for venous thrombosis.

DESIGN AND METHODS

The prevalence of the 844ins68 CBS mutation was determined in 101 patients with objectively diagnosed deep venous thrombosis and in 101 healthy controls matched for age, sex and race. PCR amplification of a DNA fragment containing exon 8 of the CBS gene was employed to determine the genotypes. Additionally, Bsrl restriction enzyme digestion of the PCR products was performed in all samples from carriers of the insertion, to test for concurrent presence of a second mutation (T833C) in the CBS gene.

RESULTS

The insertion was found in 21 out of 101 patients (20.8%; allele frequency 0.109) and in 20 out of 101 controls (19.8%; allele frequency 0.114), yielding a relative risk for venous thrombosis related to the 844ins68 CBS mutation close to 1.0. In addition, the T833C CBS mutation was detected in all alleles carrying the 844ins68 CBS insertion, confirming the co-inheritance of the two mutations.

INTERPRETATION AND CONCLUSIONS

Our findings do not support the hypothesis that the 844ins68 mutation in the CBS gene is a genetic risk factor for venous thrombosis.

Identification of a North American mosquito species, Aedes atropalpus (Diptera: Culicidae), in Italy

In late September 1996, during a routine survey for Aedes albopictus in Italy, a population of Aedes atropalpus s.s. was discovered in the Veneto Region (northern Italy). Larvae were collected in 2 tire storage areas belonging to tire recapping companies that imported loads of car and large equipment used tires from eastern Europe and North America. Aedes atropalpus is found only in North America and hence it is the origin of this species. Control measures were carried out in October, but by then any remaining Ae. atropalpus would have been diapausing in the egg stage. A follow-up survey will be conducted in the spring of 1997 to assess if Ae. atropalpus has been established in the area and the extent of the spread in Italy.

[A case of xanthogranulomatous pyelonephritis. Diagnostic and therapeutic problems]

The use of the modern diagnostic imaging techniques allows in most cases a diagnosis of nature of the lesions involving parenchymal organs. The authors report a case of renal xantogranuloma, rare pseudotumoral inflammatory pathology, treated by radical extended nephrectomy on the basis of a pre-operative diagnosis of malignant tumor. Despite the risk of false positives, in front of a renal mass whose nature is sufficiently characterized by the imaging techniques, the routine use of more invasive investigations such as arteriography and percutaneous needle biopsy seems not justified.

Efficacy of octreotide in the prevention of pancreatic fistula after elective pancreatic resections: a prospective, controlled, randomized clinical trial

BACKGROUND

A prospective, randomized controlled clinical trial was conducted in 33 Italian surgical departments with the aim of evaluating the efficacy of octreotide in the prevention of pancreatic fistula after elective pancreatic resections.

METHODS

Between July 1990 and May 1992, 278 patients were enrolled in the study. Fifty-four dropped out because of unresectable disease and six were excluded because of protocol violation; the remaining 218 were randomly assigned to the octreotide group (n = 111) or to the placebo group (n = 107). There were 131 men and 87 women with a mean age of 58.2 +/- 11.7 yrs. Pancreaticoduodenectomy was the most common operation performed (n = 143), sixty-four percent of patients had a pancreatic or periampullary cancer; chronic pancreatitis accounted for 8.2% of cases.

RESULTS

Mortality rate was 6.9%. A pancreatic fistula occurred in 31 patients (14.2%), 9% in the octreotide group and 19.6% in the placebo group (p < 0.05). Morbidity rate was significantly lower in the octreotide (21.6%) than in the placebo group (36.4%) (p < 0.05). When specific pancreatic complications were grouped together and evaluated, they occurred less frequently in the treated (15.3%) than in the placebo group (29.9%) (p < 0.05).

CONCLUSIONS

Octreotide was able to reduce significantly the incidence of pancreatic fistula after elective pancreatic resections.

[Cognitive changes in workers at a data processing company]

A study of 191 data processing workers undertaken in Porto Alegre, Brazil, in 1989, is presented. The relationship between complaints of loss of memory and their respective scores on cognitive testing in three groups of workers, one with automatized repetitive activities and two others with diversified activities, is analysed. The scores and complaints are compared with the results of a screening test for psychiatric disorders in order to verify the influence of this confounding factor. No significant evidence of cognitive problems was found despite the high prevalence of complaints of memory loss in this population (65.4%). There is a significant statistical association between these complaints and the scores of the psychiatric testing. It is suggested that futures studies should emphasize psychiatric analysis with a view to clarifying the complaints of Data Processing workers.

[Acute pseudo-obstruction of the colon (Ogilvie syndrome). Apropos of a case]

An additional case of acute colonic pseudo-obstruction (Ogilvie's syndrome) is reported. Conservative management was successful. Etiology of this syndrome is still uncertain. The aim of the treatment is to stop natural evolution to ischemia or perforation. Medical therapy, colonoscopic decompression and surgery are employed following prognostic criteria (age, cecal diameter, therapeutical delay). Mortality rate remains high, especially if complications occur. Colonoscopic decompression is a safe and efficacious first line of treatment when cecum is less than diameter 12 cm. Surgery is mandatory when perforation or ischemia are suspected and colonoscopy failed or is contraindicated.

HIV 1 and HIV 2 prevalence of seropositivity in a population of West Africa

In the month of August 1986, tests for anti-HIV 1 and anti-HIV 2 antibodies were performed in people coming to the hospital of Tanguietà (North Benin) (401 subjects) and in people working in the same hospital (23 subjects). The study revealed an anti-HIV 1 antibody prevalence of 0.4% (2/424) and an anti-HIV 2 prevalence of 0.2% (1/419). Seropositivity for both antibodies (anti-HIV 1 and anti-HIV 2) was found in one case; the other case was positive only for anti-HIV 1. The changing composition of the population due to frequent migratory displacements lead us to expect some possible alterations of the registered data in the future.

[Autocontrol of muscle relaxation with vecuronium]

The optimal conditions for maintaining desired levels of muscle relaxation with vecuronium are obtained by means of the continuous infusion (I.V.) technique. A frequent correction of the infusion flow is required, since it is impossible to predict the exact amount for the muscle relaxant in single case. In order to overcome such limits the authors propose a very feasible infusion system for the self-control of muscle relaxation; furthermore they positively consider its possible daily clinical application.

[Segmental splenectomy. Usefulness of linear surgical staplers]

As the high risk of sepsis after splenectomy is well recognized, reliable conservative surgical techniques in splenic surgery are widely advocated. Among these, segmental splenectomy carries specific and increasing indications. The use of linear staplers makes this operation quicker and safer. On the basis of a personal observation, Authors examine the anatomical features on which this operation is based, the surgical technique and the technical details to be followed using these devices. The advantages offered by staplers in this surgery allow to widen the indications to partial splenectomy, so as to yield a true primary prophylaxis of the post-splenectomy sepsis.