Biomedical subjects

F Villa

Publications and source records attributed to F Villa.

At least 19 recordsLinked to original sources

PubMed2006

Use of the Given Patency System for the screening of patients at high risk for capsule retention.

BACKGROUND: Capsule enteroscopy is a non-invasive diagnostic tool for the study of the small bowel. Due to the risk of capsule retention, capsule enteroscopy is contraindicated in patients with suspected small bowel strictures. The Given Patency Capsule is a disintegration time-controlled capsule developed to identify patients with strictures that may cause capsule enteroscopy retention. The presence of the patency capsule within the patient's body can be detected by a radio-frequency scanner. AIM OF THE STUDY: To evaluate safety and usefulness of the patency capsule in preventing capsule retention in patients at high risk. PATIENTS AND METHODS: Thirty-two patients were studied. Indications for patency capsule were: (A) Crohn's disease (18), (B) previous intestinal surgery (7), (C) previous obstruction (1), A+B (3), A+C (1), B+C (2). Patients were evaluated with the scanner at 72 h from ingestion. RESULTS: At 72 h, 24 patients had already excreted the intact capsule in the stool. Of these, two experienced abdominal pain during capsule passage. In the other eight patients, the scanner detected the presence of the patency capsule. Four of them excreted the capsule intact in the stool after 72-96 h, the remaining four never found the capsule in the stool. The 26 patients who excreted the patency capsule intact without experiencing abdominal pain were deemed eligible for the capsule enteroscopy procedure, which was performed uneventfully in the 25 who agreed to undergo the examination. CONCLUSIONS: The patency capsule is useful to identify, among patients at high risk, those who can be submitted to capsule enteroscopy without risks of capsule retention.

Adult↗

PubMed2006

The accuracy of PillCam ESO capsule endoscopy versus conventional upper endoscopy for the diagnosis of esophageal varices: a prospective three-center pilot study.

BACKGROUND AND STUDY AIMS: Variceal bleeding is a major complication of cirrhosis, and is associated with a 20 % mortality at 6 weeks. Current international guidelines recommend that patients with cirrhosis are screened by conventional upper endoscopy (esophagogastroduodenoscopy, EGD) in order to detect esophageal varices. The recently developed PillCam ESO esophageal capsule endoscope has been shown to be an accurate diagnostic tool in the investigation of patients with gastroesophageal reflux and Barrett's esophagus. We compared the PillCam ESO capsule endoscope with EGD for the detection of esophagogastric varices and portal hypertensive gastropathy in patients with cirrhosis. PATIENTS AND METHODS: A pilot trial was conducted at three sites. Patients with cirrhosis who were undergoing clinically indicated EGD for screening or surveillance for esophageal varices underwent a PillCam ESO study followed by an EGD within 48 hours. Capsule videos were assessed by an investigator who was blinded to the patient's medical history and EGD findings. RESULTS: A total of 23 of the 32 enrolled patients were found to have esophageal varices at both EGD and PillCam ESO endoscopy. In one patient PillCam ESO detected small varices that were not seen at EGD. The overall concordance between PillCam ESO and EGD was 96.9 % for the diagnosis of esophageal varices and 90.6 % for the diagnosis of portal hypertensive gastropathy. There were no adverse events related to PillCam ESO endoscopy. CONCLUSIONS: In a high-prevalence population, PillCam ESO may represent an accurate noninvasive alternative to EGD for the detection of esophageal varices and portal hypertensive gastropathy. A large-scale trial is underway to validate and expand these findings.

Endoscopes, Gastrointestinal↗

PubMed2005

Metal toxicity in municipal wastewater activated sludge investigated by multivariate analysis and in situ hybridization.

The toxicity of three heavy metals (copper, zinc and nickel) on an activated sludge biomass was studied by measuring several parameters of microbiological activity and the dynamics of microbial community composition. The effects on the microflora in the activated-sludge tank were evaluated by dosing the tank with different metal concentrations and a non-inhibiting concentration of copper for a 2-week period. The relationship between biological effects and chemical measurements was elucidated by principal component analysis (PCA). The biochemical data suggested a higher sensitivity of nitrifiers to these metals than heterotrophs. This was confirmed by fluorescent in situ hybridization (FISH) analysis on the microbial community. The impact of copper was displayed by biomass deflocculating phenomena (pin-point) and a decrease in the beta-proteo bacteria component. In addition, the zone settling velocity (ZSV) was shown not to be a good indicator of chronic toxicity phenomena. Finally, the sequence of biomass metal accumulation capability was assessed, and corresponds to Cu>Ni>Zn.

Biomass↗

PubMed2005

Sensitivity and specificity of the suspected blood identification system in video capsule enteroscopy.

BACKGROUND AND STUDY AIMS: Capsule enteroscopy has become a standard tool for the evaluation of obscure gastrointestinal bleeding. Reviewing the video recordings of capsule examinations is time-consuming and requires prolonged attention. Recently, software that can recognize the frames containing "red spots", the Suspected Blood Identification system (SBIS), has been developed with the aim of assisting in the analysis of video recordings. We assessed the sensitivity and specificity of the SBIS in patients undergoing capsule enteroscopy. PATIENTS AND METHODS: 100 consecutive patients underwent capsule enteroscopy at our tertiary referral center, for the following indications: obscure gastrointestinal bleeding (75 patients), metastatic carcinoid (7 patients) known or suspected Crohn's disease (5 patients), miscellaneous (13 patients). Capsule endoscopy was carried out by the standard method. Four gastroenterologists, experienced in capsule endoscopy, reviewed the recordings. RESULTS: Small-bowel visualization was obtained in 95 cases. The physicians identified 209 "red spots", 54 of which (25.8%) were also identified by the SBIS. The overall sensitivity, specificity, and positive and negative predictive values of the SBIS, calculated on the number of true-positive, true-negative, false-positive and false-negative results, were 40.9%, 70.7%, 69.2% and 42.6%, respectively. Sensitivity was higher for the identification of red blood (60.9%) than for nonbleeding "red" lesions such as arteriovenous malformations (25.8%). CONCLUSIONS: The SBIS has low sensitivity and specificity. It can be used as a complementary and rapid screening tool, but complete review of the recordings is still necessary.

Adult↗

PubMed2003

A simple HPLC-UV method for the assay of ginkgolic acids in Ginkgo biloba extracts.

Extracts from the leaves of Ginkgo biloba are among the most widely used phytotherapeutics. Some alkylphenols (ginkgolic acids, cardanols and cardols) have been described as potentially hazardous constituents in Ginkgo extracts. Accordingly, a requirement for a maximum concentration of ginkgolic acids has been proposed in the UE and US pharmacopoeias Ginkgo monographs establishing a limit value of 5 ppm. A novel HPLC-UV method, developed by the use of HPLC-APCI-MS HPLC-DAD techniques and allowing the identification of ginkgolic acids and related phenols, is described. The new analytical method, not requiring enrichment procedures, can be used for the quantification of ginkgolic acids in Ginkgo extracts.

Chemistry Techniques, Analytical↗

PubMed2002

Drf1, a novel regulatory subunit for human Cdc7 kinase.

Studies in model organisms have contributed to elucidate multiple levels at which regulation of eukaryotic DNA replication occurs. Cdc7, an evolutionarily conserved serine-threonine kinase, plays a pivotal role in linking cell cycle regulation to genome duplication, being essential for the firing of DNA replication origins. Binding of the cell cycle-regulated subunit Dbf4 to Cdc7 is necessary for in vitro kinase activity. This binding is also thought to be the key regulatory event that controls Cdc7 activity in cells. Here, we describe a novel human protein, Drf1, related to both human and yeast Dbf4. Drf1 is a nuclear cell cycle-regulated protein, it binds to Cdc7 and activates the kinase. Therefore, human Cdc7, like cyclin-dependent kinases, can be activated by alternative regulatory subunits. Since the Drf1 gene is either absent or not yet identified in the genome of model organisms such as yeast and Drosophila, these findings introduce a new level of complexity in the regulation of DNA replication of the human genome.

Adaptor Proteins, Signal Transducing↗

PubMed2001

High-performance liquid chromatography-electrospray ionization mass spectrometry and multiple mass spectrometry studies of hyperforin degradation products.

The alcoholic extract of the aerial parts of Hypericum perforatum L. finds wide application because of its antidepressant activity. The extract contains a number of constituents with documented biological activity including chlorogenic acid, a broad range of flavonoids, naphthodianthrones and phloroglucinols. Hyperforin and adhyperforin are the major phloroglucinol constituents found in the lipophilic fraction of the extracts. Since the stability of hyperforin has been shown to be limited, an investigation of the hyperforin degradation products using HPLC-electrospray ionization mass spectrometry and multiple mass spectrometry was undertaken.

Bridged Bicyclo Compounds↗

PubMed2001

The value of laparoscopy in the diagnosis and therapy of violin-string like perihepatic nonpostoperative adhesions.

We report three cases of Fitrz-Hugh Curtis syndrome (FHCs) that were diagnosed laparoscopically and showed microbiological or serological evidence of chlamydial infection. The case histories underscore the part played by abdominal right quadrant symptoms. In all three cases, right quadrant pain and tenderness constituted the presenting features. The patients were thought to have acute cholecystitis or acute appendicitis, but investigations proved negative. Laparoscopy was the key to the diagnosis, revealing the violin-string-like perihepatic adhesions typical of this syndrome. Lysis of the adhesions resolved the patients' symptoms of persistent severe abdominal pain. In the first case, the pain lessened dramatically only after the third operation, when the perihepatic adhesions were lysed. In the two other cases, the lysis was performed laparoscopically by fulguration and cutting. We consider this procedure to be an excellent therapeutic modality for the pain associated with FHCs.

Abdominal Pain↗

PubMed2001

Drosophila heparan sulfate 6-O-sulfotransferase (dHS6ST) gene. Structure, expression, and function in the formation of the tracheal system.

Heparan sulfate, one of the most abundant components of the cell surface and the extracellular matrix, is involved in a variety of biological processes such as growth factor signaling, cell adhesion, and enzymatic catalysis. The heparan sulfate chains have markedly heterogeneous structures in which distinct sequences of sulfate groups determine specific binding properties. Sulfation at each different position of heparan sulfate is catalyzed by distinct enzymes, sulfotransferases. In this study, we identified and characterized Drosophila heparan sulfate 6-O-sulfotransferase (dHS6ST). The deduced primary structure of dHS6ST exhibited several common features found in those of mammalian HS6STs. We confirmed that, when the protein encoded by the cDNA was expressed in COS-7 cells, it showed HS6ST activity. Whole mount in situ hybridization revealed highly specific expression of dHS6ST mRNA in embryonic tracheal cells. The spatial and temporal pattern of dHS6ST expression in these cells clearly resembles that of the Drosophila fibroblast growth factor (FGF) receptor, breathless (btl). RNA interference experiments demonstrated that reduced dHS6ST activity caused embryonic lethality and disruption of the primary branching of the tracheal system. These phenotypes were reminiscent of the defects observed in mutants of FGF signaling components. We also show that FGF-dependent mitogen-activated protein kinase activation is significantly reduced in dHS6ST double-stranded RNA-injected embryos. These findings indicate that dHS6ST is required for tracheal development in Drosophila and suggest the evolutionally conserved roles of 6-O-sulfated heparan sulfate in FGF signaling.

Amino Acid Sequence↗

PubMed2001

Closed system endotracheal suctioning maintains lung volume during volume-controlled mechanical ventilation.

OBJECTIVE: A closed suction system (CS) maintains connection with the mechanical ventilator during tracheal suctioning and is claimed to limit loss in lung volume and oxygenation. We compared changes in lung volume, oxygenation, airway pressure and hemodynamics during endotracheal suctioning performed with CS and with an open suction system (OS). DESIGN: Prospective, randomized study. SETTING: Intensive care unit in a university hospital. PATIENTS: We enrolled ten patients, volume-controlled (VC) ventilated with a Siemens Servo 900 ventilator (PaO2/FIO2 192 +/- 70, PEEP 10.7 +/- 3.9 cmH2O). INTERVENTIONS: We performed four consecutive tracheal suction maneuvers, two with CS and two with OS, at 20-min intervals. During the suction maneuvers continuous suction was applied for 20 s. MEASUREMENTS AND MAIN RESULTS: We measured end-expiratory lung volume changes (delta VL), tidal volume (VTrt), respiratory rate (RR) and minute volume (VErt) by respiratory inductive plethysmography; arterial oxygen saturation (SpO2), airway pressure and arterial pressure (PA). Loss in lung volume during OS (delta VL 1.2 +/- 0.7 l) was significantly higher than during CS (delta VL 0.14 +/- 0.1 l). During OS we observed a marked drop in SpO2, while during CS the change was only minor. During CS ventilation was not interrupted and we observed an immediate increase in RR (due to the activation of the ventilator's trigger), while VTrt decreased, VErt was maintained. CONCLUSIONS: Avoiding suction-related lung volume loss can be helpful in patients with an increased tendency to alveolar collapse; CS allows suctioning while avoiding dramatic drops in lung volumes and seems to be safe during the VC ventilation setting that we used.

Adult↗

PubMed2001

Hernioplasty and simultaneous laparoscopic cholecystectomy: a prospective randomized study of open tension-free versus laparoscopic inguinal hernia repair.

BACKGROUND: The laparoscopic repair of unilateral primary groin hernia remains controversial. This randomized study evaluates the outcome of the laparoscopic technique in hernia repair in patients undergoing simultaneous laparoscopic cholecystectomy (LC) and compares laparoscopic repair with tension-free open groin hernia repair. METHODS: Sixty-four low-risk patients with symptomatic chronic calculous cholecystitis and synchronous unilateral primary inguinal hernia were randomized to undergo either laparoscopic transabdominal preperitoneal mesh hernia repair (TAPP) and LC or LC and open tension-free hernia repair. RESULTS: The operating time was longer in the TAPP and LC group (mean +/- SD = 121 +/- 32 minutes) than in the LC and open group (95 +/- 27 minutes) (P <.01). The mean operating costs were higher in the TAPP and LC group ($1235 versus $1080) (P <.03). The intensity of postoperative pain at rest was greater in the LC and open group at 24 hours (P <.01) and 48 hours (P <.05), with a greater consumption of pain medication (P <.01). No differences between the 2 groups were found in terms of postoperative complications, disability period before return to work, or hernia recurrences. CONCLUSIONS: The totally laparoscopic procedure does not result in a significant benefit other than improved comfort in the first 2 postoperative days. However, laparoscopic hernia repair is considerably more difficult to perform than open tension-free hernioplasty. Thus, the totally laparoscopic approach should be performed only by experienced laparoscopic surgeons with special expertise in hernia surgery.

Adult↗

PubMed2001

Induced abdominal compartment syndrome increases intracranial pressure in neurotrauma patients: a prospective study.

OBJECTIVE: To evaluate the effect of a stepwise increase in intra-abdominal pressure (IAP) on intracranial pressure (ICP) and to further define the pressure transmission characteristics of different body compartments. DESIGN: A prospective, nonrandomized study. SETTING: A multidisciplinary intensive care unit at a university medical center. PATIENTS: Fifteen patients with moderate-to-severe head injury. INTERVENTIONS: All patients were studied after the initial stabilization and resolution of intracranial hypertension. Measurements were carried out before and 20 mins after IAP was increased by positioning a soft, 15-L water bag on the patient's abdomen. MEASUREMENTS AND MAIN RESULTS: Placing weights upon the abdomen generated a significant increase in IAP, which rose from 4.7 +/- 2.9 to 15.5 +/- 4.1 mm Hg (p <.001). The rise in IAP caused concomitant and rapid increases in central venous pressure (from 6.2 +/- 2.4 to 10.4 +/- 2.9 mm Hg; p <.001), internal jugular pressure (from 11.9 +/- 3.2 to 14.3 +/- 2.4 mm Hg; p <.001), and ICP (from 12.0 +/- 4.2 to 15.5 +/- 4.4 mm Hg; p <.001). Thoracic transmural pressure, calculated as the difference between central venous pressure and esophageal pressure, remained constant during the protocol. Respiratory system compliance decreased from 58.9 +/- 9.8 to 44.9 +/- 9.4 mL/cm H2O (p <.001) in all patients because of decreased chest wall compliance. The mean arterial pressure increased from 94 +/- 11 to 100 +/- 13 mm Hg (p <.01), which allowed the maintenance of a stable cerebral perfusion pressure (82.4 +/- 10.3 vs. 84.7 +/- 11.5 mm Hg; p = NS) despite the ICP increase. CONCLUSIONS: Increased IAP causes a significant rise in ICP in head trauma patients. This effect seems to be the result of an increase in intrathoracic pressure, which causes a functional obstruction to cerebral venous outflow. Routine assessment of IAP may help clinicians to identify remediable causes of increased ICP. Caution should be used when applying laparoscopic techniques in neurotrauma patients.

Abdomen↗

PubMed2000

Effects of periodic lung recruitment maneuvers on gas exchange and respiratory mechanics in mechanically ventilated acute respiratory distress syndrome (ARDS) patients.

OBJECTIVE: We wished to investigate whether volume recruitment maneuvers (VRMs) could improve alveolar recruitment and oxygenation in acute respiratory distress syndrome (ARDS) patients, ventilated at relatively low positive end-expiratory pressure (PEEP). SETTING: General intensive care unit (ICU) located in a teaching hospital. PATIENTS: 15 PEEP responder ARDS patients undergoing continuous positive pressure ventilation (CPPV) with sedation and muscle paralysis. INTERVENTIONS: We identified a low (9.4 +/- 3 cmH2O) and a high (16.0 +/- 2 cmH2O) level of PEEP associated with target oxygenation values. Using a custom modified mechanical ventilator, we applied in random order three steps lasting 30 min: (1) CPPV at the low PEEP level (CPPV(LO)); (2) CPPV at the high PEEP level (CPPV(HI)); (3) CPPV at low PEEP with the superimposition of periodic VRMs (CPPV(VRM)). VRMs were performed twice a minute by increasing PEEP to the high level for two breaths. Each brace of two breaths was spaced 30 seconds from the preceding one. MEASUREMENTS AND RESULTS: We measured gas exchange, hemodynamics, respiratory mechanics, and the end expiratory lung volume (EELV). Compared to CPPV(LO), CPPV(VRM) resulted in higher PaO2 (117.9 +/- 40.6 vs 79.4 +/- 13.6 mmHg, P < 0.01) and EELV (1.50 +/- 0.62 vs 1.26 +/- 0.50 l, P < 0.05), and in lower venous admixture (Q(VA)/Q(T)) (0.42 +/- 0.07 vs 0.48 +/- 0.07, P < 0.01). During CPPV(HI), we observed significantly higher PaO2 (139.3 +/- 32.5 mmHg) and lower Q(VA)/Q(T) (0.37 +/- 0.08) compared to CPPV(LO) (P < 0.01) and to CPPV(VRM) (P < 0.05). CONCLUSIONS: VRMs can improve oxygenation and alveolar recruitment during CPPV at relatively low PEEP, but are relatively less effective than a continuous high PEEP level.

Adult↗

PubMed2000

Economical microscope configuration for direct mycological examination with fluorescence in dermatology.

BACKGROUND: The use of fluorochromes such as Blankophor or Calcofluor allows to detect immediately and without ambiguity fungal elements in dermatological preparations. Whereas fluorescence microscopy is widely practised in clinical laboratories, it is not generally used in private practice because of the high price of a epifluorescence microscope. OBJECTIVE: To propose an economical microscope configuration to visualize fungal elements using fluorescence. METHODS: The preparations were examined with a standard microscope for routine observations, equipped with only two supplementary filters. RESULTS: Because the fungal elements produce a particularly bright fluorescence, a 25-watt halogen light is sufficient to visualize them in dermatological preparations: CONCLUSIONS: The proposed microscope configuration for direct mycological examination is particularly economical since equipment for epifluorescence and a vapour mercury lamp are not necessary.

Dermatomycoses↗

PubMed1998

Surgical treatment of poor-grade aneurysm patients.

Patients who are severely struck by subarachnoid hemorrhage (the so called poor-grades) have been usually considered almost hopeless. Conversely, it is now becoming apparent that a significant number of poor grades could be perhaps salvageable during the first hours after the hemorrhage. In this paper we are reporting the results of an aggressive management protocol including immediate intensive care management and early surgery. Early surgery was offered to all patients without vital brain destructions on CT-scan, with treatable intracranial hypertension and stabilization of vital parameters. By this attitude, among 32 initial unselected consecutive poor grades, we could manage by early surgery 15 patients (47%), obtaining 11 favourable outcomes (35%). These encouraging results in the treatment of patients otherwise destined to ominous consequences are now to be compared with the presently available less invasive endovascular techniques.

Adult↗

PubMed1998

Multidisciplinary (surgical and endovascular) approach to intracranial aneurysms.

In spite of the availability of the new endovascular technique (GDC) to manage cerebral aneurysms, to date, the crucial question "which is the proper treatment in a given patient?" still remains unsettled. In order to check whether an answer is possible, we retrospectively reviewed a personal series of 192 consecutive patients with cerebral aneurysms (1993-1995). We found 164 patients who had been considered eligible for active aneurysm treatment. Treatment modality has been chosen case by case on the basis of patient conditions, and aneurysm size and location. Four groups of patients were identified: Group 1: 104 patients (63.4%) with subarachnoid hemorrhage (SAH) in whom the treatment of choice was surgery; Group 2: 27 SAH patients (16.4%) in whom the first choice was GDC; Group 3: 7 SAH patients (4.2%) who died before the scheduled treatment; Group 4: 26 patients (15%) with not ruptured aneurysm who had either surgery or GDC. Based on the results of this series (improvement of the overall results through the multidisciplinary approach), we have developed the guidelines to prospectively manage future cases of cerebral aneurysms with the purpose to rationalize the management, thus further improving the overall results.

Aged↗

PubMed1997

Complex arteriovenous fistula of the brain in an infant. Case report.

A rare case of complex cerebral arteriovenous fistula in an infant is reported. An 8-month-old boy first presented with a syndrome of increased intracranial pressure. Neuroradiological assessment showed a direct intracerebral arteriovenous shunt with marked venous engorgement. No hemorrhage was evident. Direct surgical treatment was decided. Clinical and radioanatomical cure was achieved. The main angiographic and pathophysiologic features of this unusual entity, as well as the available therapeutic options, are reviewed and discussed.

Arteriovenous Fistula↗

PubMed1997

Cavernous hemangioma of the skull. Case report and review of the literature.

Osseous hemangiomas are rare skeletal tumors that constitute 0.7% of all osseous neoplasms. The most common site is the vertebral column while involvement of the calvarium is extremely rare accounting for 0.2% of all bone neoplasm. The authors present a case of a 35-years-old man who was admitted with right parietal swelling and review the gross appearance, pathogenesis, histopathology, radiological features and treatment of this neoplasm.

Adult↗