The Effect of Denture Adhesives on Denture Quality and Occlusal Force

INTRODUCTION

Complete dentures (CDs) have been associated with substantial problems regarding edentulous patient's function. Denture adhesives seem to be useful adjuncts to improving retention and stability.

METHODS

A clinical study was undertaken to investigate the effect of a denture adhesive (DA) on function in complete denture wearers along with the quality of their CDs. Thirty complete denture wearers participated in the study. The first phase of the experimental procedure comprised 3 groups of measurements performed at 3 distinct time points: the initial measurement (T1), a 2nd measurement after 15 days of DA daily application (T2), and a 3rd measurement following a 15-day washout period (T3). The second phase consisted of the follow-up measurements. The measurements included: recording of relative occlusal force (ROF), distribution of occlusal contacts (DOC) and center of force (COF) using the T-Scan 9.1 device and functional assessment of dentures using the FAD index.

RESULTS

The DA use induced a statistically significant increase in ROF (p-value=0.003) and decrease in COF (p-value⟨0.001) and DOC (p-value=0.001). The overall FAD score significantly improved (p-value⟨0.001).

CONCLUSIONS

The use of the DA improved the occlusal force, the distribution of occlusal contacts as well as the qualitative characteristics of CDs.

Emergency Urology procedures during the COVID-19 pandemic in the UK: A 3-month prospective study

OBJECTIVE

COVID-19 resulted in Regional tiered restrictions being introduced across the UK with subsequent implications for planned and emergency surgical care. Specific to Merseyside, Tier 4, Tier 2 and Tier 5 restrictions were introduced in late 2020 and early 2021. The purpose of this study was to examine the nature and workload of emergency urological procedures during three different national lockdown Tiers in the North West of England.

METHOD

A 3-month prospective study examining all emergency urological activity was conducted from November 2020 when Tier 4 restrictions were introduced and included Tier 2 restrictions in December and then concluded at the end of January 2021 when Tier 5 restrictions were in place. Data was obtained by identifying patients using the electronic theatre listing system.

RESULTS

A total of 71 emergency cases were performed (24 in November (Tier 4), 28 in December (Tier 2), 19 in January 2021 (Tier 5)) with 15 different types of procedures performed. The most frequently performed procedure was stent insertion (36), followed by scrotal exploration (10). The least commonly performed procedure was suprapubic catheter insertion under general anaesthesia (1). One patient required transfer to a different hospital. In total 6 calls were made by general surgery and 3 by gynaecology for urgent urological assistance in theatre. Three urology patients returned to the theatre as emergencies following elective procedures.

CONCLUSION

Unlike the Spring lockdown, acute urological presentations requiring operative intervention still presented daily. Of the 71 cases performed, most occurred in Tier 2. Stent insertion was the most commonly performed procedure, with the majority of the cases performed by registrars.

National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK

A national, multi-centre audit of non-melanoma skin cancer excisions by plastic surgery.

β-eye: A benchtop system for in vivo molecular screening of labeled compounds

Preclinical nuclear molecular imaging speeds up the mean time from synthesis to market, in drug development process. Commercial imaging systems have in general high cost, require high-cost service contracts, special facilities and trained staff. In the current work, we present β-eye, a benchtop system for in vivo molecular screening of labeled compounds with Positron Emission Tomography (PET) isotopes. The developed system is based on a dual-head geometry, offering simplicity and decreased cost. The goal of the design is to provide 2D, real-time radionuclide images of mice, allowing the recording of fast frames and thus perform fast kinetic studies, with spatial resolution of ∼2 mm. Performance evaluation demonstrates the ability of β-eye to provide quantitative results for injected activities lower than 1.5 MBq, which is adequate for pharmacodynamic studies in small mice.

1234 Emergency Urology Procedures During COVID-19 Pandemic: A 2 Monthly Prospective Study

Introduction

COVID-19 resulted in Regional tiered restrictions being introduced across the UK with subsequent implications for planned and emergency care. Specific to Merseyside Tier 4 and Tier 2 restrictions were introduced in late 2020. At the onset of the pandemic in the Spring, elective work ceased, and emergency admissions were minimal. The purpose of this study was to examine the volume and nature of all emergency admissions to a Urology unit in Merseyside in the 2nd wave of the pandemic during two different tiers of national restrictions.

Method

A prospective audit examining all emergency urological activity was conducted in Whiston Hospital from October 2020 when the Tier 4 restrictions were introduced to Tier 2 was introduced. Data was obtained by identifying patients using the electronic theatre listing system.

Results

A total of 52 emergency cases were performed (24 in November Tier 4, 28 in December Tier 2). A total of 12 different procedures were performed. The commonest procedure performed was stent insertion (26), followed by scrotal exploration (7). One patient required transfer to a different hospital. In total 4 calls were made by general surgery and 2 by gynaecology for urological assistance in theatre. Two urology patients returned to theatre. Direct Consultant involvement occurred in 19 cases (37%).

Conclusions

Unlike the Spring lockdown acute urology operations presented despite regional restrictions. A total of 52 cases were performed with more occurring in Tier 2. Stent insertion was the commonest procedure with the majority of the cases performed by registrars.

Benchtop systems for in vivo molecular screening of labeled compounds, as a tool to speed up drug research

BACKGROUND

For every new drug, >10,000 candidate molecules are tested for ~15 years. This is the daily mission of thousands research teams worldwide. It is well proven that small animal imaging speeds up this work, increases accuracy and decreases costs. However, commercial imaging systems have high purchase cost, require high service contracts, special facilities and trained staff. Thus, they are affordable to only few large research centres and not to the majority of small and medium research teams internationally. There are two main reasons that urge the addressing of this problem at large scale now: Firstly, small animal imaging started in 2000 and quickly research community and pharma industry understood its value, which opened preclinical imaging market (>2.5 Bil $). Continuous evolution in medicine and biology clearly shows the need to speed up research using new tools. Asian countries rapidly invest funds in drug research, enlarging existing market. Secondly, until recently such systems were based on complicated electronics and expensive components. Evolution in detector technology, electronics, software and 3D printing, made feasible the development of benchtop imaging systems, with attractive end user price.

MATERIALS AND METHODS

Being an active partner of numerous international and national projects, we tried to identify the main requirements that an imaging system should have, in order to become a screening tool for daily use. Thus, we recently developed a new generation of affordable, but high-performance imaging systems, which can fulfil the daily needs of all research labs activated in preclinical research. Our technology covers the field of SPECT (Single Photon Emission Computed Tomography) and PET (Positron Emission Tomography) imaging, while an optical and x-ray imaging system is under development. The systems are based on well tested technology, including pixeliated scintillators, Position Sensitive Photomultipliers, programmable ADCs (Analog to Digital Converters) and FPGAs (Field Programmable Gate Arrays) and are connected with a standard laptop through USB and Ethernet connection. The systems are named "eyes-series" and have been already tested for fast screening of small animals injected with labeled compounds including peptides, antibodies and nanoparticles. Besides their performance, they are offered at a fraction of the cost of the commercial ones, comparable to standard lab equipment such as HPLC, gamma counter etc, opening new prospects in preclinical research. The first system is called "γ-eye™" and it is a dedicated system for imaging photons (γ-rays) which are emitted from radiolabelled biomolecules (2D-SPECT). The second system is called "β-eye™" and detects positrons (β-rays) from similar biomolecules (2D-PET). They both have dimensions which are 35x35x30cm and weight which is less that 30kgr. The spatial resolution of both systems is <2mm and their energy resolution <20%. Their sensitivity allows real time imaging for the first second post injection, while images are shown in real time during acquisition. They allow recording of fast frames, down to 1min, thus it is possible to perform fast kinetic studies. Finally, they are both provided along with a laptop that has preinstalled the required software, named "VISUAL-eyes".

RESULTS

The technical specifications and performance evaluation of our technology will be presented. Different applications including oncology, regenerative medicine, nanomedicine and lung imaging will be given. Finally, the results of the comparison against high performance systems and a typical workflow for optimizing throughput will be demonstrated.

An international study to revise the EORTC questionnaire for assessing quality of life in lung cancer patients

BACKGROUND

The European Organization for Research and Treatment of Cancer (EORTC) QLQ-LC13 was the first module to be used in conjunction with the core questionnaire, the QLQ-C30. Since the publication of the LC13 in 1994, major advances have occurred in the treatment of lung cancer. Given this, an update of the EORTC QLQ-LC13 was undertaken.

METHODS

The study followed phases I to III of the EORTC Module Development Guidelines. Phase I generated relevant quality-of-life issues using a mix of sources including the involvement of 108 lung cancer patients. Phase II transformed issues into questionnaire items. In an international multicenter study (phase III), patients completed both the EORTC QLQ-C30 and the 48-item provisional lung cancer module generated in phases I and II. Patients rated each of the items regarding relevance, comprehensibility, and acceptance. Patient ratings were assessed against a set of prespecified statistical criteria. Descriptive statistics and basic psychometric analyses were carried out.

RESULTS

The phase III study enrolled 200 patients with histologically confirmed lung cancer from 12 centers in nine countries (Cyprus, Germany, Italy, Israel, Spain, Norway, Poland, Taiwan, and the UK). Mean age was 64 years (39 - 91), 59% of the patients were male, 82% had non-small-cell lung cancer, and 56% were treated with palliative intent. Twenty-nine of the 48 questions met the criteria for inclusion.

CONCLUSIONS

The resulting module with 29 questions, thus currently named EORTC QLQ-LC29, retained 12 of the 13 original items, supplemented with 17 items that primarily assess treatment side-effects of traditional and newer therapies.

Oral Mucositis: understanding the pathology and management

Oral Mucositis is a common complication of cancer therapy which may limit the completion of treatment and affect the quality of life of the patient. As we have come to understand its pathogenesis new developments in its management and prevention have allowed us minimize this side effect.

Outbreak of Salmonella Enteritidis phage type 13a: case-control investigation in Hertsmere, United Kingdom

Binary file ES_Abstracts_Final_ECDC.txt matches

Changes in serum sodium concentration after transurethral procedures

The aim of this study is to evaluate the changes in serum sodium concentration and the degree of correlation with factors such as the amount of intravenous fluid intake, the kind and the amount of irrigating fluids and the duration of the procedure. In this framework, 98 male patients who underwent transurethral procedure were studied and the correlation between the magnitude of hyponatraemia and the above-mentioned parameters was evaluated. All procedures were performed under spinal anesthesia and a solution of either manitol-sorbitol or sterilized water was used as irrigation fluid. Serum sodium concentration was measured before and after the procedure, while the kind and amount of the irrigating fluids, the amount of fluid intake and the duration of the procedure were also recorded. The patients were divided into three groups according to the duration of the procedure (i) <30 min, (ii) 30-60 min, and (iii) >60 min. Significant reduction in serum sodium concentration was found postoperatively (P < 0.001) and this was more profound in procedures longer than 1 h. This reduction was strongly correlated only with the duration of the transurethral procedure (P < 0.01). In conclusion, in transurethral procedures the reduction in serum sodium is postoperatively related to the duration of the procedure, while the intravenous and irrigating fluids to play no role on it.

Spontaneous rupture of the rectosigmoid with small bowel evisceration through the anus

Spontaneous rupture of the rectosigmoid with small bowel evisceration through the anus is a rare and acute condition of the gastrointestinal tract. After Brodie's first description, only 52 such cases have been reported in the literature. An 83-year-old woman experienced a sudden, spontaneous rectosigmoid rupture and protrusion of small bowel loops, through the ruptured colon and out of the anus. After an immediate management, an emergency operation was performed, and a small bowel resection and suturing of the ruptured rectosigmoid were carried out for restoration of bowel continuity. On the 41st postoperative day, a massive cerebro-vascular accident (CVA) was the cause of the patient's death. Discussion of the aetiology and treatment of this rare condition.

Preincisional local infiltration of levobupivacaine vs ropivacaine for pain control after laparoscopic cholecystectomy

BACKGROUND

Postoperative pain is less intense after laparoscopic surgery than after open surgery. However, patients may gain additional benefit from a preincisional local infiltration of anesthetic. The aim of this study was to compare the analgesic efficacy of two local anesthetics, ropivacaine and levobupivacaine, for tissue infiltration as a means of improving postoperative pain control after laparoscopic cholecystectomy.

METHODS

Using a randomized, double-blind study design, 57 American Society of Anesthesiologists (ASA) I and II patients scheduled for laparoscopic cholecystectomy were randomly assigned to receive local infiltration with 0.9% saline solution (Placebo group, n = 18), ropivacaine 1% (Rop group, n = 20), or levobupivacaine 0.5% (Lev group, n = 19). The local anesthetic was administered, prior to trocar placement, using the same technique and delivering the same volume (20 ml) for all three groups. The anesthetic technique was standardized for all groups. Postoperative pain was rated at 2 h, 4 h, and 24 h postoperatively by visual analogue scale (VAS) score. Cumulative analgesic consumption and adverse effects were also recorded. Data were analyzed by analysis of variance (ANOVA), followed by a post hoc test.

RESULTS

The Lev and Rop groups did not differ significantly in their VAS scores at 2 h postoperatively, but the Lev group experienced significantly ( p < 0.001) less pain than the Placebo and Rop groups at 4 h and 24 h postoperatively. The Rop group registered significantly lower VAS scores ( p < 0.001) than the Placebo group at 4 h postoperatively. Additionally, the consumption of analgesics was significantly lower in the Lev group than in the Rop ( p < 0.01) and Placebo ( p < 0.001) groups, and patients in the Rop group consumed significantly less analgesics ( p < 0.001) than the to patients in the Placebo group.

CONCLUSION

Local tissue infiltration with levobupivacaine is more effective than ropivacaine in reducing the postoperative pain associated with laparoscopic cholecystectomy.

Sufentanil or clonidine for blunting the increase in intraocular pressure during rapid-sequence induction

BACKGROUND AND OBJECTIVE

The aim was to determine if the intravenous administration of sufentanil or clonidine before the induction of anaesthesia could obtund the increase of intraocular pressure associated with rapid-sequence induction.

METHODS

Thirty-two ASA I-II patients with no history of eye illness scheduled for elective non-ophthalmic surgery were randomly assigned to receive either sufentanil 0.05 microg kg(-1) i.v. (Group A, n = 15) or clonidine 2 microg kg(-1) i.v. (Group B, n = 17) prior to induction. General anaesthesia was induced with thiopental (5 mg kg(-1)) followed by succinylcholine 1 mg kg(-1) to facilitate tracheal intubation. The general anaesthetic technique was standardized in both groups. Intraocular pressure was measured using the Schioetz tonometer just before the succinylcholine administration (t0), just before tracheal intubation (t1) and immediately after intubation (t2). Mean arterial pressure and heart rate were recorded at the same time intervals.

RESULTS

Intraocular pressures were similar in both groups at t0, but the sufentanil group had significantly lower values compared with the clonidine group just before (t1) and immediately after tracheal intubation (t2).

CONCLUSIONS

Sufentanil is effective in blunting the increase in intraocular pressure caused by rapid-sequence induction with succinylcholine, while clonidine did not seem to have any effect in intraocular pressures just before (t1) and just after (t2) intubation.

Tropisetron vs ondansetron for prevention of postoperative nausea and vomiting after laparoscopic cholecystectomy: a randomized double-blind, placebo-controlled study

BACKGROUND

Postoperative nausea and vomiting are observed in increased frequency after laparoscopic surgery. This study was performed in order to compare the efficacy of two 5-hydroxytryptamine-3 (5-HT3) receptor antagonists, ondansetron and tropisetron, in preventing postoperative nausea and vomiting (PONV) after laparoscopic cholecystectomy.

METHODS

Using a randomized, double-blind study design, 87 ASA I and II patients scheduled for laparoscopic cholecystectomy were randomly assigned to receive 4 mg ondansetron (Group A, n = 29), 5 mg tropisetron (Group B, n = 31), or placebo (Group C, n = 27) intravenously (IV) before induction of anesthesia. The end points evaluated were frequency of nausea, nausea intensity rated on a scale from 1 (mild) to 5 (most severe), frequency of vomiting, and need for rescue antiemetics. These parameters were measured immediately after surgery (0 h), at 3 h, 6 h, and 12 h postoperatively.

RESULTS

The frequency of nausea was significantly higher in group A (31.2%) compared to group B (14%) at 12 h postoperatively (p <0.01). However, patients of group A had significantly lower nausea scores at 3 h postoperatively compared to group B. Postoperative vomiting occurred in 13.8% of patients in group A and 9.6% of patients in group B throughout the whole study period (p = n.s.). The need for rescue antiemetics was similar between groups A and B. Both groups were superior to placebo concerning all studied parameters.

CONCLUSION

Our results show that ondansetron may be more effective in controlling nausea intensity during the first 3 h after laparoscopic cholecystectomy, while tropisetron has a longer-acting activity, with a major impact on nausea frequency at 12 h postoperatively.

The Drosophila neuregulin vein maintains glial survival during axon guidance in the CNS

Neuron-glia interactions are necessary for the formation of the longitudinal axon trajectories in the Drosophila central nervous system. Longitudinal glial cells are required for axon guidance and fasciculation, and pioneer neurons for trophic support of the glia. Neuregulin is a neuronal molecule that controls glial survival in the vertebrate nervous system. The Drosophila protein Vein has structural similarities with Neuregulin. We show here that Vein functions like a Neuregulin to maintain glial cell survival. We present direct in vivo evidence at single-cell resolution that Vein is produced by pioneer neurons and maintains the survival of neighboring longitudinal glia. This mechanism links axon guidance to control of glial cell number and may contribute to plasticity during the establishment of normal axonal trajectories.

Preincisional intravenous low-dose ketamine and local infiltration with ropivacaine reduces postoperative pain after laparoscopic cholecystectomy

BACKGROUND

The preincisional use of ketamine combined with local tissue infiltration with Ropivacaine may reduce noxious input during surgery. The goal of this study was to examine whether this combination improves postoperative pain control after laparoscopic cholecystectomy.

METHODS

A total of 55 patients were randomly assigned to one of three groups. Group 1 received placebos preincisional. Group 2 received preincisional saline IV and local infiltration with 20 ml ropivacaine (10 mg/ml). Group 3 received preincisional ketamine 1 mg/kg IV and local infiltration with 20 ml ropivacaine (10 mg/ml). Postoperative pain was rated at 0, 3, 6, 12, 24, and 48 h postoperatively by visual analogue scale scores (VAS). Cumulative analgesic consumption and time until first analgesic medication request were recorded.

RESULTS

Group 3 experienced significantly (p < 0.05) less pain than group 2 at 6 h and 12 h postoperatively. Groups 2 and 3 did not differ significantly by VAS at 0 h, 3 h, 24 h, and 48 h. Group 1 had significantly higher VAS scores than groups 2 and 3 at 0 h, 3 h, 6 h, 12 h, and 24 h postoperatively. The consumption of analgesics was significantly higher in group 1 than in groups 2 and 3. Although the consumption of analgesics was higher in group 3 than in group 2, this difference did not reach statistical significance. The time to first request for analgesics was significantly longer in groups 2 and 3 than in group 1, with no statistical difference between groups 2 and 3.

CONCLUSION

Preincisional treatment with low-dose IV ketamine and local infiltration with ropivacaine 1% reduces postoperative pain after laparoscopic cholecystectomy.

Diuretic MAG3 scintigraphy (F0) in acute pyelonephritis: regional parenchymal dysfunction and comparison with DMSA

99mTc-DMSA late static planar imaging or SPECT is being used for the investigation of focal acute pyelonephritis (APN), especially in children with urinary tract infection (UTI). Diuretic 99mTc-mercaptoacetyltriglycine (MAG3) dynamic scintirenography has been applied in the evaluation of kidney function and structure, frequently to exclude obstruction. However, in children and adults with a clinical picture of APN, diuretic MAG3 scintigraphy with zero time injection of furosemide (MAG3-F0) was observed to display focal parenchymal abnormalities; regional dysfunction (focal parenchymal decrease in early uptake; slow filling in and prolonged late retention of activity); or, less frequently, fixed defects. This observation was further studied both retrospectively and prospectively, and its sensitivity and specificity for APN were compared with those of dimercaptosuccinic acid (DMSA).

METHODS

In the retrospective study, for 36 children with UTI and regional parenchymal findings on MAG3-F(0), data were reviewed, analyzed, and compared with the results of concurrent DMSA studies. In the prospective study, for 57 children with clinical and laboratory findings suggestive of APN, the 2 radiopharmaceuticals were used for imaging sequentially and the results of the 2 studies were compared. The criteria for abnormal findings compatible with the diagnosis of APN were, for MAG3-F(0), regional parenchymal dysfunction and fixed focal defects and, for DMSA, focal defects without parenchymal loss.

RESULTS

In all groups of patients, most abnormal MAG3-F(0) studies (80%) showed regional parenchymal dysfunction, but in some (20%) a fixed defect was found. Compared with DMSA and when both regional dysfunction and focal defects were considered, MAG3-F(0) was as sensitive as DMSA. Some patients had only MAG3-F(0) abnormalities, suggesting a slightly lower specificity for MAG3-F(0) compared with DMSA (86%); this finding needs further study, because it also raises questions about the sensitivity of DMSA, considering that only a small percentage of patients with clinically suggestive findings had abnormal study findings. In most patients with fixed defects on both DMSA and MAG3-F(0), follow-up studies showed no resolution, suggesting that a fixed defect on MAG3-F(0) may indicate either more severe APN or preexistent scars and that regional dysfunction may be a sign more specific for APN and prognostic of potential recovery. In addition, a pattern more specific for a scar--a fixed defect with a dilated regional calyx--was seen on follow-up MAG3-F(0).

CONCLUSION

A fast (25-min) planar dynamic MAG3-F(0) study was found to be as sensitive at depicting focal parenchymal abnormalities in APN as was the 3- to 4-h DMSA routine procedure. The sensitivity and specificity of both studies need further evaluation.

Identification of an alleged offender of murder by VNTR analysis: case report

DNA typing was used to demonstrate that three human body pieces found disposed of in the countryside around Athens and the suspicions about the perpetrator's identity were connected. Reverse paternity testing was attempted by comparative typing of three variable number tandem repeats loci in the remains, as well as in the presumptive parents and sister of the decedent, demonstrating Mendelian inheritance of the alleles of the loci analyzed. Confronting the results of the abovementioned analysis, the suspect accepted the accusation.

Breast cyst simulating metastases on iodine-131 imaging in thyroid carcinoma

False-positive radioiodine uptake has been reported in many organ systems. We describe a female patient who had mixed papillary and follicular thyroid carcinoma, and on radioiodine total-body imaging demonstrated focal, lower-right chest uptake. Special prone imaging with the right breast dependent proved that the uptake was inside the right breast. Review of a recent breast ultrasound and mammograms showed this uptake to correspond to a large breast cyst. It is known that 131I breast uptake may be functional within the mammary gland. In this patient, it was due to retention within the cyst after the background activity decreased. Knowledge of this phenomenon may improve the interpretation of total-body 131INa studies.

Fluoroquinolone resistance mutations in the parC, parE, and gyrA genes of clinical isolates of viridans group streptococci

The nucleotide sequences of the quinolone resistance-determining regions (QRDRs) of the parC and gyrA genes from seven ciprofloxacin-resistant (Cpr) isolates of viridans group streptococci (two high-level Cpr Streptococcus oralis and five low-level Cpr Streptococcus mitis isolates) were determined and compared with those obtained from susceptible isolates. The nucleotide sequences of the QRDRs of the parE and gyrB genes from the five low-level Cpr S. mitis isolates and from the NCTC 12261 type strain were also analyzed. Four of these low-level Cpr isolates had changes affecting the subunits of DNA topoisomerase IV: three in Ser-79 (to Phe or Ile) of ParC and one in ParE at a position not previously described to be involved in quinolone resistance (Pro-424). One isolate did not show any mutation. The two high-level Cpr S. oralis isolates showed mutations affecting equivalent residue positions of ParC and GyrA, namely, Ser-79 to Phe and Ser-81 to Phe or Tyr, respectively. The parC mutations were able to transform Streptococcus pneumoniae to ciprofloxacin resistance, while the gyrA mutations transformed S. pneumoniae only when mutations in parC were present. These results suggest that DNA topoisomerase IV is a primary target of ciprofloxacin in viridans group streptococci, DNA gyrase being a secondary target.

Acute poisoning due to alkalis used during industrial cleaning of soft drinks' glass containers: a case report

Corrosive alkalis are used in the soft drink and beer industries for the cleaning of the non-disposable glass containers using several different methods. It is well understood that complete cleaning of these vessels by multiple and well-organized rinsing is an absolute necessity. In cases of disturbance of this process, some residuals of alkaline agents may be retained in the glass containers, causing severe health risks to consumers. This case of acute poisoning due to caustic alkalis concerns a young woman who consumed carbonated lemonade from a non-disposable glass container. Clinical signs and symptoms and the treatment of the affected woman are described. Toxicological analysis of the soft drink consumed led to the detection, identification and quantitative determination of the presence of the alkalis.

Nuclear medicine applications to the neuroimaging of AIDS. A neuroradiologist's perspective

The human immunodeficiency virus (HIV) responsible for AIDS is reaching epidemic proportions in the United States and Europe. As new therapeutic modalities against HIV are uncovered and applied to treat prophylactically asymptomatic and therapeutically symptomatic HIV positive patients, imaging studies are no longer used just to characterize the organic-morphologic effects of HIV and opportunistic infections and neoplasms. This article discusses the current applications and contribution of nuclear medicine to the management of neurologically symptomatic HIV-positive patients.

Primary central nervous system lymphoma in patients with AIDS

Primary central nervous system lymphoma (PCNSL), once considered a rare brain neoplasm, has been steadily increasing in incidence mainly due to an enlarging population of immunosuppressed patients. PCNSL has become the second most common brain space occupying lesion in patients with the acquired immunodeficiency syndrome. A rapid diagnosis of this entity may represent weeks to months of survival to immunosuppressed HIV-positive patients. The radiologist now plays an important role in the noninvasive diagnosis and management of this condition through the accurate interpretation of imaging findings provided by CT, MR, and brain SPECT studies. This article focuses on the pathogenesis, clinical manifestations, neuropathology, and imaging characteristics of this brain neoplasm. New accurate imaging algorithms combining the diagnostic information provided by CT, MR, and T1-201 brain SPECT are discussed.

Long-term persistence of ciprofloxacin-resistant Haemophilus influenzae in patients with cystic fibrosis

Ciprofloxacin has been a major advance in the treatment of chronic respiratory infections. Three patients with cystic fibrosis and colonized by 5 nontypeable Haemophilus influenzae strains exhibiting low- (MIC, 2 microg/mL) and high-level ciprofloxacin resistance (MICs, 16-32 microg/mL) are described. The patients had received several courses of ciprofloxacin. These MICs represent a decrease in ciprofloxacin susceptibility of 200-3200 times. Molecular epidemiologic methods demonstrated that 2 patients were chronically colonized by their own ciprofloxacin-resistant strains for > or = 15-17 months. Three strains showed simultaneous resistance to ampicillin and chloramphenicol by enzyme inactivation, and 2 had ampicillin resistance without beta-lactamase activity. These data suggest that the emergence and long-term persistence of ciprofloxacin-resistant H. influenzae in patients with cystic fibrosis can be a consequence of antibiotic treatment.

Ciprofloxacin-resistant Haemophilus influenzae strains possess mutations in analogous positions of GyrA and ParC

The nucleotide sequences of the quinolone resistance-determining regions of the gyrA and parC genes from five ciprofloxacin-resistant strains of Haemophilus influenzae (MICs, 2 to 32 micrograms/ml) isolated from patients with cystic fibrosis and three ciprofloxacin-susceptible strains of H. influenzae (MICs, < or = 0.1 micrograms/ml) were determined. Four of the five resistant strains possessed at least one amino acid substitution in each of the GyrA and ParC fragments studied. The mutations identified in GyrA were a serine at residue 84 (Ser-84) to Leu or Tyr and Asp-88 to Asn or Tyr. ParC mutations were in positions exactly analogous to those identified in GyrA, namely, Ser-84 to Ile and Glu-88 to Lys. The Glu-88 to Lys ParC substitution was identified only in high-level ciprofloxacin-resistant strains. These mutations have been shown to be the origin of the observed resistance after transformation into ciprofloxacin-susceptible H. influenzae isolates. These results suggest that H. influenzae isolates require at least one amino acid substitution in both GyrA and ParC in order to attain significant levels of resistance to quinolones.