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PubMed2005

Hyphal differentiation in the exploring mycelium of Aspergillus niger.

Mycelial fungi play a central role in element cycling in nature by degrading dead organic material such as wood. Fungal colonization of a substrate starts with the invasion of exploring hyphae. These hyphae secrete enzymes that convert the organic material into small molecules that can be taken up by the fungus to serve as nutrients. Using green fluorescent protein (GFP) as a reporter, we show for the first time that exploring hyphae of Aspergillus niger differentiate with respect to enzyme secretion; some strongly express the glucoamylase gene glaA, while others hardly express it at all. When a cytoplasmic GFP was used, 27% of the exploring hyphae of a 5-day-old colony belonged to the low expressing hyphae. By fusing GFP to glucoamylase and by introducing an ER retention signal, this number increased to 50%. This difference is due to cytoplasmic streaming of the reporter in the former case, as was shown by using a photo-activatable GFP. Our findings indicate that a fungal mycelium is highly differentiated, especially when taking into account that hyphae in the exploration zone were exposed to the same nutritional conditions.

Aspergillus niger↗

PubMed1975

Suggested new rules for exploration of the common bile duct at cholecystectomy.

Traditional indications for exploration of the common bile duct have been made anachronistic by developments in operative cholangiography. A new technique of contact cholangiography, described in this paper, improves the precision of operative cholangiography and allows the traditional indications for exploration to be modified. A new set of guidelines for exploration of the common duct, based on high-quality operative cholangiography, is outlined, and the place of the supraduodenal and transduodenal routes for exploration is discussed. The results of the application of these policies in a series of 120 cholecystectomies are presented.

Cholangiography↗

PubMed1978

Twenty years' experience with parathyroid exploration.

Eighty-four patients have undergone surgical exploration following a clinical diagnosis of hyperpathyroidism over a 20-year period. Urinary tract calculi were the major indication for exploration, and 90% of these patients had recurrent calculi. Osteitis fibrosa was a rare presentation of hyperparathyroidism. Lethargy, sometimes profound, was an important symptom, in some instances the dominant feature. Persistent hypercalcaemia remains the chief diagnostic investigation, with helpful confirmation from estimation of the parathyroid hormone level. Little attempt was made in this series to utilize preoperative localization techniques, reliance being placed on meticulous bloodless surgery to find normal and abnormal parathyroid tissue. Eighty-five explorations were carried out in the 84 patients. Seventy-four of the explorations were successful, converting the patient to a normocalcaemic state. Of these, 63 had a single adenoma (86%).

Adenoma↗

PubMed2005

Ectopic adrenocortical tissue found at groin exploration in children: incidence in relation to diagnosis, age and sex.

OBJECTIVE: To assess the incidence of ectopic adrenocortical tissue (EACT) in the groin in children, and examine the relationship between the incidence and the underlying diagnosis, age and sex. PATIENTS AND METHODS: From computer records, all groin explorations between 1988 and 2002 in patients < or = 15 years old were identified. Cases of EACT were identified from computer histology records, and the incidence in different groups compared. RESULTS: Of 935 groin explorations, EACT was identified in 25 (2.7%); there were no cases in girls. The incidence was 0.7% at inguinal herniotomy (IH), 4.1% at ligation of the patent processus vaginalis for communicating hydrocele (P = 0.03 vs IH), and 3.3% at exploration for undescended testes (P = 0.02 vs IH). In boys with undescended testes the incidence of EACT was similar in different age groups (0-7 years, 3.3%; 8-15 years 3.2%, P = 0.96). CONCLUSIONS: The overall incidence of EACT at groin exploration was 2.7%, with none detected in girls. There was no evidence of involution of EACT with increasing age. The incidence of EACT varied with the underlying diagnosis, but the reason for this is unknown.

Adrenal Cortex↗

PubMed2006

Evaluation of findings during re-exploration for obstructive ileus after radical cystectomy and ileal-loop urinary diversion: insight into potential technical improvements.

OBJECTIVE: To retrospectively evaluate the findings during re-exploration for obstructive ileus after radical cystectomy (RC) and ileal conduit diversion. PATIENTS AND METHODS: During a 12-year period, 434 patients who had RC and ileal conduit diversion were retrospectively evaluated for the diagnosis of early (</=30 days after RC) or late abdominal re-exploration. The operative reports of patients requiring a second abdominal procedure were reviewed, evaluating in particular the reason for small bowel obstruction (SBO). In addition, the type of entero-enteric anastomosis and the retroperitonealization of the uretero-enteric anastomosis were compared between patients who required abdominal re-exploration for SBO and those who did not. RESULTS: Abdominal re-exploration for SBO was necessary for 14 (3.2%) and 32 (7.3%) patients in the early and late postoperative period, respectively. The most common reasons for SBO were anastomotic malfunction (1.4%) and malignant recurrence (2.8%). Adhesions were the second most common cause leading to ileus in both periods (1.1% and 2.3%, respectively). When there was no retroperitonealization of the uretero-enteric anastomosis, SBO occurred more often both early and late (P = 0.06). Early anastomotic malfunction leading to SBO was more common (but not statistically significant, P = 0.06) when the entero-enteric anastomosis was hand-sutured end-to-end. CONCLUSIONS: Anastomotic malfunction, bowel adhesions and internal hernias are responsible for SBO early after surgery. The above reasons, in addition to malignant recurrence, are the most common reasons for SBO in the late postoperative period.

Aged↗

PubMed1994

The influence of temperament and mothering on attachment and exploration: an experimental manipulation of sensitive responsiveness among lower-class mothers with irritable infants.

6-month-old infants selected on irritability shortly after birth and their mothers were randomly assigned to 2 intervention and 2 control groups to test the hypothesis that enhancing maternal sensitive responsiveness will improve quality of mother-infant interaction, infant exploration, and attachment. The intervention lasted 3 months and ended when the child was 9 months of age. When infants were 9 months of age, intervention group mothers were significantly more responsive, stimulating, visually attentive, and controlling of their infant's behavior than control group mothers. Intervention infants had higher scores than control infants on sociability, self-soothing, and exploration, and they cried less. Quality of exploration also improved, with intervention infants engaged in cognitively sophisticated kinds of exploration more than control infants. At 12 months of age, significantly more intervention group dyads were securely attached than control group dyads.

Adult↗

PubMed1992

Etiology of acute scrotum at surgical exploration in children, adolescents and adults.

Between January 1970 and December 1989, 171 patients underwent scrotal exploration for acute scrotum (an acute painful swelling of the scrotum or its content), at our hospital. Of 70 children scrotal explorations, torsion of appendages was found in 33 cases (47%). Torsion of testis was found in 24 patients (34%). Of the 84 adolescent scrotal explorations performed, 72 (86%) had torsion of testis, and 8 (9%) had torsion of appendages. Of 17 adults, torsion of testis was found in 15 cases (88%). These results clarify that unnecessary explorations are much more common in children (66%) than in adolescents and adults (14%). We therefore suggest using radionuclear scans and/or Doppler ultrasound to facilitate clinical diagnosis in the children group.

Acute Disease↗

PubMed2002

Bioinspired engineering of exploration systems for NASA and DoD.

A new approach called bioinspired engineering of exploration systems (BEES) and its value for solving pressing NASA and DoD needs are described. Insects (for example honeybees and dragonflies) cope remarkably well with their world, despite possessing a brain containing less than 0.01% as many neurons as the human brain. Although most insects have immobile eyes with fixed focus optics and lack stereo vision, they use a number of ingenious, computationally simple strategies for perceiving their world in three dimensions and navigating successfully within it. We are distilling selected insect-inspired strategies to obtain novel solutions for navigation, hazard avoidance, altitude hold, stable flight, terrain following, and gentle deployment of payload. Such functionality provides potential solutions for future autonomous robotic space and planetary explorers. A BEES approach to developing lightweight low-power autonomous flight systems should be useful for flight control of such biomorphic flyers for both NASA and DoD needs. Recent biological studies of mammalian retinas confirm that representations of multiple features of the visual world are systematically parsed and processed in parallel. Features are mapped to a stack of cellular strata within the retina. Each of these representations can be efficiently modeled in semiconductor cellular nonlinear network (CNN) chips. We describe recent breakthroughs in exploring the feasibility of the unique blending of insect strategies of navigation with mammalian visual search, pattern recognition, and image understanding into hybrid biomorphic flyers for future planetary and terrestrial applications. We describe a few future mission scenarios for Mars exploration, uniquely enabled by these newly developed biomorphic flyers.

Algorithms↗

PubMed2006

Djinn Lite: a tool for customised gene transcript modelling, annotation-data enrichment and exploration.

BACKGROUND: There is an ever increasing rate of data made available on genetic variation, transcriptomes and proteomes. Similarly, a growing variety of bioinformatic programs are becoming available from many diverse sources, designed to identify a myriad of sequence patterns considered to have potential biological importance within inter-genic regions, genes, transcripts, and proteins. However, biologists require easy to use, uncomplicated tools to integrate this information, visualise and print gene annotations. Integrating this information usually requires considerable informatics skills, and comprehensive knowledge of the data format to make full use of this information. Tools are needed to explore gene model variants by allowing users the ability to create alternative transcript models using novel combinations of exons not necessarily represented in current database deposits of mRNA/cDNA sequences. RESULTS: Djinn Lite is designed to be an intuitive program for storing and visually exploring of custom annotations relating to a eukaryotic gene sequence and its modelled gene products. In particular, it is helpful in developing hypothesis regarding alternate splicing of transcripts by allowing the construction of model transcripts and inspection of their resulting translations. It facilitates the ability to view a gene and its gene products in one synchronised graphical view, allowing one to drill down into sequence related data. Colour highlighting of selected sequences and added annotations further supports exploration, visualisation of sequence regions and motifs known or predicted to be biologically significant. CONCLUSION: Gene annotating remains an ongoing and challenging task that will continue as gene structures, gene transcription repertoires, disease loci, protein products and their interactions become more precisely defined. Djinn Lite offers an accessible interface to help accumulate, enrich, and individualize sequence annotations relating to a gene, its transcripts and translations. The mechanism of transcript definition and creation, and subsequent navigation and exploration of features, are very intuitive and demand only a short learning curve. Ultimately, Djinn Lite can form the basis for providing valuable clues to plan new experiments, providing storage of sequences and annotations for dedication to customised projects. The application is appropriate for Windows 98-ME-2000-XP-2003 operating systems.

Alternative Splicing↗

PubMed2006

A tool for exploring space-time patterns: an animation user research.

BACKGROUND: Ever since Dr. John Snow (1813-1854) used a case map to identify water well as the source of a cholera outbreak in London in the 1800s, the use of spatio-temporal maps have become vital tools in a wide range of disease mapping and control initiatives. The increasing use of spatio-temporal maps in these life-threatening sectors warrants that they are accurate, and easy to interpret to enable prompt decision making by health experts. Similar spatio-temporal maps are observed in urban growth and census mapping--all critical aspects a of a country's socio-economic development. In this paper, a user test research was carried out to determine the effectiveness of spatio-temporal maps (animation) in exploring geospatial structures encompassing disease, urban and census mapping. RESULTS: Three types of animation were used, namely; passive, interactive and inference-based animation, with the key differences between them being on the level of interactivity and complementary domain knowledge that each offers to the user. Passive animation maintains the view only status. The user has no control over its contents and dynamic variables. Interactive animation provides users with the basic media player controls, navigation and orientation tools. Inference-based animation incorporates these interactive capabilities together with a complementary automated intelligent view that alerts users to interesting patterns, trends or anomalies that may be inherent in the data sets. The test focussed on the role of animation passive and interactive capabilities in exploring space-time patterns by engaging test-subjects in thinking aloud evaluation protocol. The test subjects were selected from a geoinformatics (map reading, interpretation and analysis abilities) background. Every test-subject used each of the three types of animation and their performances for each session assessed. The results show that interactivity in animation is a preferred exploratory tool in identifying, interpreting and providing explanations about observed geospatial phenomena. Also, exploring geospatial data structures using animation is best achieved using provocative interactive tools such as was seen with the inference-based animation. The visual methods employed using the three types of animation are all related and together these patterns confirm the exploratory cognitive structure and processes for visualization tools. CONCLUSION: The generic types of animation as defined in this paper play a crucial role in facilitating the visualization of geospatial data. These animations can be created and their contents defined based on the user's presentational and exploratory needs. For highly explorative tasks, maintaining a link between the data sets and the animation is crucial to enabling a rich and effective knowledge discovery environment.

Computer Graphics↗

PubMed2004

The effects of methylphenidate on novel object exploration in weanling and periadolescent rats.

Methylphenidate (Ritalin) is used in the treatment of attention-deficit hyperactivity disorder. Surprisingly, little research has been conducted on the effects of methylphenidate during early development. Therefore, the present study was conducted to examine the effects of methylphenidate on object exploration in developing rats. Male and female weanling (21-day-old) and periadolescent (34-day-old) Sprague-Dawley rats were tested after acute or chronic treatment with methylphenidate. In weanling rats, chronic methylphenidate (5.0 mg/kg) increased locomotor activity and disrupted novel object exploration. In periadolescent rats, methylphenidate disrupted exploration of the novel object, but had no effect on locomotor activity at any dose tested. Periadolescent rats appear to be less sensitive to methylphenidate-induced changes in activity compared to weanling animals, whereas methylphenidate disrupted novel object exploration in both ages. Our results suggest that methylphenidate may alter recognition memory and/or reactivity to or preference for novelty.

Age Factors↗

PubMed2005

Does sac size matter? Findings based on surgical exploration of excluded abdominal aortic aneurysms.

PURPOSE: To prospectively examine the outcomes of excluded abdominal aortic aneurysms (AAA) that continue to expand without evidence of endoleak. METHODS: From 1984 to 1998, 1218 patients underwent operative retroperitoneal exclusion of AAA and aortoiliac reconstructions. During the procedure, the aneurysm sac was ligated proximally, as well as distally, which created an ideal in-vivo model of excluded AAA sacs with or without endoleaks. From January 2002 to June 2003, 15 of these patients were identified as having an increase in AAA sac size with or without an endoleak on duplex ultrasonography. These patients were prospectively evaluated by computed tomography and diagnostic arteriography. Patients with a demonstrable endoleak underwent embolization, and the remainder underwent open surgical exploration. RESULTS: Eight patients had arteriographically demonstrated endoleaks that were treated with coil embolization. The remaining 7 patients (6 men; mean age 76 years, range 68-81) without a demonstrable endoleak underwent elective surgical exploration and sac endoaneurysmorrhaphy. The mean time interval between the original surgery and aneurysm sac exploration was 76 months (range 52-92); during this time, the mean aneurysm sac size increased by 2.7 cm (range 1.3-5.2). The mean sac pressure was 53 mmHg, and the sac walls were noticeably thickened, with markedly dilated vasa vasorum. The sac contained yellow, fibrinous material with clear serous fluid (5 patients without any evidence of retrograde flow) or liquefied thrombus with serosanguinous fluid (2 patients with retrograde flow from lumbar arteries). No AAA sacs were pulsatile. CONCLUSIONS: Continued expansion of excluded AAA sacs can occur from causes other than a missed endoleak. Exudation of fluid from thickened sac wall and vasa vasorum, as well as local enzymatic activity, might lead to the formation of a sac hygroma. Furthermore, these findings raise questions as to the need for surgical exploration of all patients with an enlarging AAA sac in the setting of low sac pressures and no definable endoleak.

Aged↗

PubMed2003

Transabdominal sonography before uterine exploration as a predictor of retained placental fragments.

OBJECTIVE: To evaluate the diagnostic accuracy of sonography in postpartum patients thought to have retained placental fragments. METHODS: The study group consisted of 39 postpartum women in whom inspection of the placenta brought up suspicion of retained placental fragments. All these women underwent manual exploration of the uterine cavity. Before the procedure, all patients had two-dimensional sonographic imaging, after which they were divided into 2 groups. The first group comprised women who were judged to have had an empty uterus or nothing but intrauterine fluid collection. The second group consisted of those in whom sonography showed echoes of what might appear as residual trophoblastic tissue, that is, echogenic, hypoechoic, or mixed echo intracavitary patterns. The sonographic patterns were then correlated with the presence or absence of retained placental fragments as found on uterine manual exploration and pathologic examination. RESULTS: In 18 patients, no suspected contents were observed on sonography. In 17 of these patients, the uterus was empty on manual uterine exploration. One of these patients had residual trophoblastic tissue, which was of minimal quantity and clinically unimportant. In 21 patients, sonography suggested retained placental tissue. In 15 of these patients, pathologic examination confirmed residual trophoblastic tissue, and in the remaining 6, the uterus contained blood clots, decidua, or both. CONCLUSIONS: Sonography is an effective tool for evaluating postpartum patients thought to have retained placental fragments. Normal sonographic findings might obviate the need for manual exploration of the uterine cavity. A questionable sonographic result is not an effective tool for distinguishing between placental fragments and blood clots.

Abdomen↗

PubMedDate not supplied

Reliability of tactile perception using sharp and dull explorers in marginal opening identification.

PURPOSE: The most direct method to clinically evaluate marginal openings in fixed partial dentures is to use manual explorers for tactile perception. The purpose of this in vitro study was to establish the reliability of different instruments for discovering marginal openings. MATERIALS AND METHODS: The materials used in this study included a dull stylet and a sharp-tipped explorer as well as a metal cylinder surface featuring 9 "V"-shaped circumferential grooves ranging in size from 20 to 165 microns. A group of 42 subjects were asked to discover the grooves using both instruments. RESULTS: The data revealed high reliability in the use of the sharp-tipped explorer. With this instrument, a defect of 36 microns could be perceived by 95% of the subjects. The dull, worn instrument gave significantly inferior results (P < 0.05). CONCLUSION: Using a sharp-tipped explorer on a smooth metal surface, tactile perception is a reliable means of detecting open margin defects up to 36 microns wide. As has been suggested in previous studies, the difficulty seems to be not in defect detection but in the evaluation of the clinical acceptability once it is detected.

Crowns↗

PubMed1998

Ultrasound-guided unilateral neck exploration for sporadic primary hyperparathyroidism: is it worthwhile?

The role of preoperative localisation tests before initial neck exploration for primary hyperparathyroidism (PHP) remains controversial, as does the optimal surgical approach. We report our experience with preoperative ultrasound (US) and the operative management of sporadic PHP between 1990 and 1995. Preoperative US was carried out by an experienced radiologist. Three surgeons adopted a policy of 'selective' US-guided unilateral neck exploration (UNE); the fourth surgeon performed routine bilateral neck exploration (BNE). There were 72 patients: 26 men and 46 women, with a mean age of 57.4 +/- 12.5 years (range 21-80 years). All patients underwent initial neck exploration for 'sporadic' PHP, of whom 63 had preoperative US. This was positive in 52 patients; 27 of whom underwent a UNE, 23 had a BNE, and two patients had a UNE converted to a BNE. Patients with 'negative' US (n = 11), and those receiving no preoperative localisation test (n = 90) underwent a BNE. The sensitivity, specificity and accuracy of US were 80% (52/65), 100% (61/61), and 90% (113/126), respectively. Comparable success rates were achieved (BNE: 97% (33/34) vs UNE: 93% (27/29), P < 0.05), with very low morbidity. Failures with the scan-guided UNE were caused by missed contralateral adenomas. An experienced radiologist and a low incidence of multiglandular disease (MGD) are essential prerequisites for the scan-guided unilateral approach. An experienced surgeon, on the other hand, is the only prerequisite for the 'gold standard' bilateral approach.

Adenoma↗

PubMed1999

[Scarred uterus: is routine exploration of the cesarean scar after vaginal birth always necessary?].

OBJECTIVE OF THE STUDY: To determine the risks and benefits of routine transcervical revision of previous cesarean uterine scar in patients with successful vaginal delivery. MATERIAL AND METHODS: Retrospective study, over a 10-year period, of a routine palpation practice in the two units of our Obstetric department. Then, a 30-month prospective study comparing, in each unit, two different attitudes toward uterine revision (routine exploration vs symptomatic patients exploration) was conducted. RESULTS: The retrospective part of our study led us to report 3 uterine ruptures (0.43% of all scarred uterus) and 14 dehiscences (2%) during the ten years. All uterine ruptures were sufficiently symptomatic in order to be suspected prior to scar exploration. No dehiscence needed surgical treatment. Some patients with bloodless dehiscence and no repair had subsequent vaginal deliveries with no scar separation found on uterine exploration. In the prospective part of our study, we found a significative difference in the occurrence of fever (18.9% vs 9.9%; p < 0.05) and antibiotic treatment (22.8% vs 12.7%; p < 0.05) between the two groups based on attitude toward uterine revision. CONCLUSION: These data suggest that transcervical revision of previous cesarean uterine scar should be performed only in symptomatic patients (persistent suprapubic pain, placental retention, excessive bleeding during labor or delivery) or when risk factors are present (prolonged labor, prolonged expulsive efforts, instrumental extraction).

Adult↗

PubMed2002

[Selective parathyroidectomy with unilateral cervical exploration for primary hyperparathyroidism].

Primary hyperparathyroidism (pHPT), is caused in over 90% of the cases by a single parathyroid adenoma. Preoperative diagnostic imaging techniques, in particular dual phase scintigraphy with SestaMIBI/TC99 and high frequency probe ecography, are able to pinpoint it 90% of the time. These are the two cornerstones of modern pHPT surgery, which has witnessed the passage from cervical exploration of all the most common parathyroid glandular sites to a more carefully targeted, restricted approach in the side of the neck where the adenoma is suspected to be. This is how selective parathyroidectomy with unilateral cervical exploration and, recently, mini-invasive parathyroidectomy, came into being. Between 1996 and 2001, in the Otolaryngology Department of S. Maria della Misericordia Hospital in Udine, 39 patients affected by pHPT, half of whom (49%) were asymptomatic, underwent selective parathyroidectomy with unilateral cervical exploration. The object of this paper was to evaluate the efficacy of this surgical technique by comparing the pre- and post-operative calcaemia and parathormone levels. The normalization of these parameters, and particularly of the latter, was considered indicative of successful treatment. All the postoperative calcaemia levels were normal, while elevated parathormone levels persisted in only 2 cases (5%). Our statistics showed a 95% efficacy for selective parathyroidectomy, a result that is comparable to the percentages described in the literature. There were, furthermore, no significant peri- or postoperative complications in any of the cases. These observations, together with the brief operating times required for the procedure (20-25 minutes on average) and the low cost of the material employed, enable us to conclude that selective parathyroidectomy with unilateral cervical exploration continues to hold its own as a valid option in the present scenario of surgical pHPT treatment, also in consideration of the fact that it does not present the rigid inclusion criteria characteristics of mini-invasive techniques.

Adult↗

PubMed1998

Rehabilitation of Visuospatial Cognition and Visual Exploration in Neglect: a Cross-over Study.

Right hemispheric brain damage is often accompanied by visual neglect of contralesional hemispace as well as profound visuospatial and visuoconstructive disorders. Despite some recent improvements in the treatment of neglect, few therapeutic approaches exist for disorders of visuospatial cognition and none has dealt with the question of how both disorders can be treated in combination. In the present cross-over rehabilitation study, thirteen neglect patients first received visual exploration training for six weeks followed by visuospatial training for four weeks. Eleven patients had a right-hemispheric lesion, 2 a left-hemispheric lesion. Ten subjects had parietal cortical lesions, 3 lesions were outside the parietal lobe. In the first treatment phase the patients received training, using computer controlled devices, intended to improve visual search and reading strategies. In the second phase of treatment, visual orientation discrimination was trained on a PC-monitor with verbal feedback by the therapist. Significant improvements were obtained after exploration training regarding the extent of visual search-field witbin the neglected hemifield, visual search performance in the whole visual field, reading time and reading errors but there was no change after visuospatial training for any of these measures. The reverse pattern was observed for visuospatial training: significant improvements were observed in line orientation judgements, clock perception, mental transposition of angles, horizontal writing and visuoconstructive abilities, but there was no change in any of these tests during exploration training. Feedback-based training of visual orientation discrimination revealed rapid (within 8-15 sessions) and stable improvements in this ability and a transfer to spatially related tasks.No significant correlations were obtained between training-related improvements and the time since brain damage for 9 of 10 tests, indicating that spontaneous recovery had no effect on the improvements during the two treatments. Likewise, no influence of age and gender on treatment progress was found. The phase-specific improvements in this study suggest that specific and differential treatment is necessary and effective for the treatment of visual exploration and visuospatial disorders in patients with visual neglect. Moreover, they indicate that feedback-based visual learning may prove an effective device in the neurorehabilitation of brain-damaged patients.

Journal Article↗