'Getting control of Corona takes many angles': COVID-19 vaccine knowledge, attitudes and beliefs among refugee/immigrant/migrant communities in four US cities

The objectives of the study were to (i) document refugee, immigrant and migrant (RIM) communities' knowledge, attitudes and beliefs (KABs) related to the Coronavirus disease (COVID-19) vaccine and (ii) identify best practices for developing and disseminating culturally and linguistically responsive health messaging addressing those KABs. Thirteen online focus groups (OFGs) in 10 languages were conducted. Each OFG was conducted in the participants' native language. OFGs were recorded, transcribed, translated and uploaded to qualitative software for coding. A thematic analysis was conducted. Results suggest that while there was some variation between different language groups (e.g. whether religious leaders were seen as trusted sources of information about COVID), there were also important commonalities. Most language groups (i) alluded to hearing about or having gaps in knowledge about COVID-19/the COVID-19 vaccine, (ii) reported hearing negative or conflicting stories about the vaccine and (iii) shared concerns about the negative side effects of the vaccine. There continues to be a need for health messaging in RIM communities that is culturally and linguistically concordant and follows health literacy guidelines. Message content about the COVID-19 vaccine should focus on vaccine importance, effectiveness and safety, should be multimodal and should be primarily delivered by healthcare professionals and community members who have already been vaccinated.

Water filtration by endobenthic sandprawns enhances resilience against eutrophication under experimental global change conditions

Identifying processes that confer resilience against global change is a scientific challenge but is central to managing ecosystem functionality in future. Detecting resilience-enhancing mechanisms is especially relevant in coastal ecosystems, where multi-stressor interactions can drive degradation over time. Here, we quantify the resilience-conferring potential of endobenthic sandprawns against eutrophication, including under high temperatures. We show using a global change mesocosm experiment that sandprawn presence was associated with declines in phytoplankton biomass, particularly under eutrophic conditions, where sandprawns reduced phytoplankton biomass by approximately 74% and prevented a shift to extreme eutrophy. Eutrophic waters were nanophytoplankton-dominated, but sandprawn presence countered this, resulting in even contributions of pico- and nanophytoplankton. Our findings highlight the potential for sandprawns to increase resilience against eutrophication by limiting phytoplankton blooms, preventing extreme eutrophy and counteracting nanophytoplankton dominance. Incorporating endobenthic crustaceans into resilience-based management practices can assist in arresting future water quality declines in coastal ecosystems.

Management of Otogenic Sigmoid Sinus Thrombosis: A Systematic Review on the Role of Anticoagulation and its Outcome

To provide a systematic review on the use of additional anticoagulation in the management of otogenic sigmoid sinus thrombosis when compared with the cohort not receiving the anticoagulation. A systematic review until 2021 was done and relevant studies were screened. Based on a selective criteria, a database is constituted which were then rearranged and studied. 16 articles were selected with 113 patients. The group who received anticoagulation had more complications (23.33%) in comparison (21.74%), whereas the recanalization was successful in the anticoagulated group, 76.67%, as against 39.13%. In 74/90 patients who underwent mastoidectomy with anticoagulation, the recanalization and complication were 72.97% and 25.68% respectively. The second group with 16/90 patients who received conservative treatment, the recanalization and complication rates were 93.75% and 12.50% respectively. The third group with 23 patients were treated with mastoidectomy and antibiotics but didn't receive anticoagulants in which the recanalization achieved in 39.13% with a complication rate of 21.74%. For those patients who underwent mastoidectomy with concurrent anticoagulation, 44 showed radiological evidence of recanalization, and in sixteen patients that received the same treatment, no recanalization was achieved whereas in patients who received conservative treatment with anticoagulation, 12 patients showed recanalization and finally, for the patients underwent surgery without anticoagulation, five patients achieved recanalization and 7 did not become recanalized (14.29%). Recanalization seems more pronounced in those who were anticoagulated, but, did not seem to influence the clinical outcome. Complications were more in those who were undergone surgery with or without anticoagulation.

School nurse and COVID-19 response

The role of the school nurse should not be understated when addressing the Covid-19 pandemic and its effects on children and families. Knowledge surrounding this virus is rapidly changing and quick adaptation within the school system is required. In addition to the provision of direct care and education to students, school nurse responsibilities include the development and implementation of new policies; consideration of social and emotional well-being; and effective communication with students, families, teachers, administrators, and community stakeholders. This article addresses current evidence related to the coronavirus disease 2019 (COVID-19) pandemic and the evolving role of the school nurse. A case study incorporates tips and suggestions for school nurses who will deliver professional care during this COVID-19 crisis.

Cadaveric White Matter Dissection Study of the Telencephalic Flexure: Surgical Implications

Neurosurgery has traditionally been overtly focused on the study of anatomy and functions of cortical areas with microsurgical techniques aimed at preserving eloquent cortices. In the last two decades, there has been ever-increasing data emerging from advances in neuroimaging (principally diffusion tensor imaging) and clinical studies (principally from awake surgeries) that point to the important contribution of white matter tracts (WMT) that influence neurological function as part of a brain network. Major scientific consortiums worldwide, currently working on this human brain connectome, are providing evidence that is dramatically altering the manner in which we view neurosurgical procedures. The development of the telencephalic flexure, a major landmark during the human embryogenesis of the central nervous system (CNS), severely affects the cortical/subcortical anatomy in and around the sylvian fissure and thus the different interacting brain networks. Indeed, the telencephalic flexure modifies the anatomy of the human brain with the more posterior areas becoming ventral and lateral and associative fibers connecting the anterior areas with the previous posterior ones follow the flexure, thus becoming semicircular. In these areas, the projection, association, and commissural fibers intermingle with some WMT remaining curved and others longitudinal. Essentially the ultimate shape and location of these tracts are determined by the development of the telencephalic flexure. Five adult human brains were dissected (medial to lateral and lateral to medial) with a view to describing this intricate anatomy. To better understand the 3D orientation of the WMT of the region we have correlated the cadaveric data with the anatomy presented in the literature of the flexure during human neuro-embryogenesis in addition to cross-species comparisons of the flexure. The precise definition of the connectome of the telencephalic flexure is primordial during glioma surgery and for disconnective epilepsy surgery in this region.

Aqueous-Based Low-Temperature Synthesis and Thin-Film Properties of Oxysulfide BiCuOS Nanoparticles

BiCuOS is a nontoxic p-type semiconductor that is a promising candidate for photoelectric applications. The formation of thin films with a good electronic transport at the grain boundaries, while avoiding thermal treatment detrimental to its chemical stability is a challenge. We have developed a chemical method for the direct synthesis of stable colloidal suspensions of BiCuOS nanoparticles from soluble precursors. These colloidal solutions were stabilized with a catechol functionalized poly-3-hexylthiophene that allows easy spin-coating deposition and favors electronic transport along the grain boundaries. Stacking of ZnO-BiCuOS layers were achieved, allowing preparation of n-p junctions. These act as rectifying diodes and are strongly photosensitive, with I_ph /I_dark =85 corresponding to an enhancement of the photocurrent of more than two orders of magnitude compared to that of BiCuOS alone. This energy-efficient and low-cost method is a further step in the development of new sulfide semiconductor devices.

Adding diffusion ordered NMR spectroscopy (DOSY) to the arsenal for characterizing paramagnetic complexes

Herein we report the development of diffusion ordered NMR spectroscopy (DOSY) for its use to characterize metal complexes containing paramagnetic first row transition metal elements. This technique is capable of assessing the purity and speciation of paramagnetic complexes, and also provides a convenient method to provide qualitative and sometimes quantitative molecular weight data.

A primer on the genetics of medullary thyroid cancer

Medullary thyroid cancer is a rare type of neuroendocrine tumour that arises from the parafollicular cells (C cells) of the thyroid gland. It accounts for 3%-5% of thyroid cancer cases. Close to 25% of cases are familial, and 75% are considered sporadic. Familial cases are associated with a germline RET mutation; 43%-65% of sporadic cases harbour a somatic event in the gene. Germline RET mutations are associated with the autosomal-dominant inherited multiple endocrine neoplasia (men) 2a and 2b syndromes and the isolated familial medullary thyroid cancer syndrome. More than 100 RET codon mutations have been reported to date, with genotype-phenotype correlations that include the extent and aggressiveness of the medullary thyroid cancer and the presence of other features of the men2 syndromes. The latter include pheochromocytoma-paraganglioma, hyperparathyroidism, cutaneous lichen amyloidosis, and Hirschsprung disease. In this narrative review, we focus on RET proto-oncogene physiology and pathogenesis induced by germline and somatic RET mutations, the genotype-phenotype correlation, and the management and follow-up of patients with germline-mutated medullary thyroid cancer.

Diagnosis and pathologic characteristics of medullary thyroid carcinoma-review of current guidelines

Background

Medullary thyroid carcinoma (mtc) is a rare malignancy of the thyroid gland, and raising awareness of the recommended diagnostic workup and pathologic characteristics of this malignancy is therefore important.

Methods

We reviewed the current clinical practice guidelines and recent literature on mtc, and here, we summarize the recommendations for its diagnosis and workup. We also provide an overview of the pathology of mtc.

Results

A neuroendocrine tumour, mtc arises from parafollicular cells ("C cells"), which secrete calcitonin. As part of the multiple endocrine neoplasia (men) type 2 syndromes, mtc can occur sporadically or in a hereditary form. This usually poorly delineated and infiltrative tumour is composed of solid nests of discohesive cells within a fibrous stroma that might also contain amyloid. Suspicious nodules on thyroid ultrasonography should be assessed with fine-needle aspiration (fna). If a diagnosis of mtc is made on fna, patients require baseline measurements of serum calcitonin and carcinoembryonic antigen. Calcitonin levels greater than 500 pg/mL or clinical suspicion for metastatic disease dictate the need for further imaging studies. All patients should undergo dna analysis for RET mutations to diagnose men type 2 syndromes, and if positive, they should be assessed for possible pheochromocytoma and hyperparathyroidism.

Summary

Although the initial diagnosis of a suspicious thyroid nodule is the same for differentiated thyroid carcinoma and mtc, the remainder of the workup and diagnosis for mtc is distinct.

Host-specific differences in the contribution of an ESBL IncI1 plasmid to intestinal colonization by Escherichia coli O104:H4

Objectives

To assess stability and contribution of a large ESBL-encoding IncI1 plasmid to intestinal colonization by Escherichia coli O104:H4 in two different mammalian hosts.

Methods

Specific-pathogen-free 3-4-day-old New Zealand White rabbits and conventionally reared 6-week-old weaned lambs were orally infected with WT E. coli O104:H4 or the ESBL-plasmid-cured derivative, and the recovery of bacteria in intestinal homogenates and faeces monitored over time.

Results

Carriage of the ESBL plasmid had differing impacts on E. coli O104:H4 colonization of the two experimental hosts. The plasmid-cured strain was recovered at significantly higher levels than WT during late-stage colonization of rabbits, but at lower levels than WT in sheep. Regardless of the animal host, the ESBL plasmid was stably maintained in virtually all in vivo passaged bacteria that were examined.

Conclusions

These findings suggest that carriage of ESBL plasmids has distinct effects on the host bacterium depending upon the animal species it encounters and demonstrates that, as for E. coli O157:H7, ruminants could represent a potential transmission reservoir.

Elevated Serum Endothelin-1 Levels in Patients with Colorectal Cancer; Relevance for Prognosis

Background

It has been demonstrated that the Doppler Perfusion Index (DPI) is increased in patients who are at risk of developing liver metastases from colorectal cancer. It has been postulated that a circulating hormonal factor is involved in the relative vasoconstriction throughout the splanchnic bed. Endothelin-1 (ET-1), a potent vasoconstrictor which has been associated with tumor growth and is produced by colorectal tumors, may play an important role in this phenomenon. In this paper the prognostic value of serum ET-1 in colorectal cancer is discussed.

Methods

Preoperative serum levels of ET-1 were assessed in three groups of patients: group A underwent resection of the colorectal tumor and remained free of recurrence (n=20); group B developed metachronous liver metastases at least six months after colorectal resection (n=14); and group C presented with colorectal cancer and synchronous liver metastases (n=22).

Results

The mean (SD) serum ET-1 levels in groups A, B and C were 1.59 (0.41) pmol/L, 1.70 (0.32) pmol/L and 1.85 (0.47) pmol/L, respectively. These values were significantly different from those of healthy controls (1.22 (0.31), p<0.05). Kaplan-Meier analyses revealed no prognostic value of preoperative serum ET-1 levels.

Conclusions

These preliminary results demonstrate that serum ET-1 levels are raised in patients with colorectal cancer. Serum ET-1 levels do not seem to be of prognostic value for survival.

Sleep deprivation in nursing students: The negative impact for quality and safety

Objective: The purpose of this pilot study was to understand nursing students’ perception of the relationship between sleep deprivation and learning, and personal and patient safety when in a clinical or work setting.Methods: Design: The researchers used a cross-sectional correlational design. Setting: The study was conducted in a Mid-western state university school of nursing with an average of 400 undergraduate pre-licensure nursing students. Sample: All 328 undergraduate pre-licensure nursing students were invited to participate in the study. The convenience sample of 179 (response rate of 55%) pre-licensure, nursing students completed the study. Methodology: The Sleep Deprivation of Nursing Students, a 4-point Likert scale questionnaire, consisted of demographic questions and forty-five questions on personal sleep habits, caffeine/stimulant use, and sleep inducing aids, motor vehicle safety, spare time activities, and safety during work and clinical experiences.Results: One hundred and fifty-five (n = 155) students needed seven or more hours of sleep daily to feel rested, but received less than 5 hours/day. All participants reported (n = 179) feeling sleep deprived.  Sleep inducing aids were used by (n = 56) participants, and (n = 35) took stimulants to stay awake. Students (n = 166) worked 8 or more hours at a job, and (n = 158) had at some 12 hour school clinical rotations, and (n = 64) reported a combined clinical and work of five to greater than 12 consecutive days. Students (n = 172) believed they provided safe practice at work and (n = 174) and safe practice in a clinical setting. Some students reported being awake 17-19 hours. The majority of students (n = 144) believed 12-hour-clinicals were too long, yet more than half of the students preferred 12-hour work and clinical experiences.Conclusions: Nursing students may lack the knowledge that chronic sleep deprivation may result in personal and patient safety issues when in a clinical or work setting. Students are potentially exposing themselves to acute and chronic health problems as a result of sleep deprivation and the use of substances to remain awake or obtain sleep. Nurse educators and nurse managers must collaborate to reduce the number of consecutive clinical and work shifts, limit overtime hours, and better educate students on the negative impact of sleep deprivation. 

Is a questionnaire and radiograph-based follow-up model for patients with primary hip and knee arthroplasty a viable alternative to traditional regular outpatient follow-up clinic?

AIMS

Increasing demand for total hip and knee arthroplasty (THA/TKA) and associated follow-up has placed huge demands on orthopaedic services. Feasible follow-up mechanisms are therefore essential.

METHODS

We conducted an audit of clinical follow-up decision-making for THA/TKA based on questionnaire/radiograph review compared with local practice of Arthroplasty Care Practitioner (ACP)-led outpatient follow-up. In all 599 patients attending an ACP-led THA/TKA follow-up clinic had a pelvic/knee radiograph, completed a pain/function questionnaire and were reviewed by an ACP. An experienced orthopaedic surgeon reviewed the same radiographs and questionnaires, without patient contact or knowledge of the ACP's decision. Each pathway classified patients into: urgent review, annual monitoring, routine follow-up or discharge.

RESULTS

In total, 401 hip and 198 knee patients were included. There was substantial agreement between the ACP and surgeon for both hip (kappa = 0.69, 95% confidence interval (CI) 0.62 to 0.76) and knee (kappa = 0.81, 95% CI 0.74 to 0.88). Positive agreement was very high for discharge and routine follow-up; however the ACP was more likely to select annual monitoring and the surgeon urgent review.

DISCUSSION

Review of the questionnaire/radiograph together identified all patients in need of increased surveillance, with good agreement for on-going patient management. However, review of the radiograph or questionnaire alone missed some patients with potential problems. A radiograph in conjunction with a questionnaire as a review may represent a cost effective THA/TKA follow-up mechanism.

TAKE HOME MESSAGE

A questionnaire and radiograph-based remote review may represent a cost-effective total joint arthroplasty follow-up mechanism; thereby reducing the considerable burden that follow-up currently places on the NHS.

Nurses Identify Education and Communication Among Professionals as Essential in Serving ASD Children

Autism spectrum disorder (ASD) is a broad term encompassing a group of neurodevelopmental disabilities. Children with ASD present behavioral, communication, and social behaviors. One in 68 individuals is diagnosed with autism. With ASD prevalence continuing to rise, it makes sense for school nurses to identify areas that may be helpful in serving this population. This school nurse focus group study shared specific areas that would benefit school nurses when working with children with autism. Two glaring trends surfaced from the focus group--continuing education needs and communication among all school professionals (i.e., teachers, special education services).

Specific recommendations for accurate and direct use of PET-CT in PET guided radiotherapy for head and neck sites

PURPOSE

To provide specific experience-based guidance and recommendations for centers wishing to develop, validate, and implement an accurate and efficient process for directly using positron emission tomography-computed tomography (PET-CT) for the radiotherapy planning of head and neck cancer patients.

METHODS

A PET-CT system was modified with hard-top couch, external lasers and radiotherapy immobilization and indexing devices and was subject to a commissioning and quality assurance program. PET-CT imaging protocols were developed specifically for radiotherapy planning and the image quality and pathway tested using phantoms and five patients recruited into an in-house study. Security and accuracy of data transfer was tested throughout the whole data pathway. The patient pathway was fully established and tested ready for implementation in a PET-guided dose-escalation trial for head and neck cancer patients.

RESULTS

Couch deflection was greater than for departmental CT simulator machines. An area of high attenuation in the couch generated image artifacts and adjustments were made accordingly. Using newly developed protocols CT image quality was suitable to maintain delineation and treatment accuracy. Upon transfer of data to the treatment planning system a half pixel offset between PET and CT was observed and corrected. By taking this into account, PET to CT alignment accuracy was maintained below 1 mm in all systems in the data pathway. Transfer of structures delineated in the PET fusion software to the radiotherapy treatment planning system was validated.

CONCLUSIONS

A method to perform direct PET-guided radiotherapy planning was successfully validated and specific recommendations were developed to assist other centers. Of major concern is ensuring that the quality of PET and CT data is appropriate for radiotherapy treatment planning and on-treatment verification. Couch movements can be compromised, bore-size can be a limitation for certain immobilization techniques, laser positioning may affect setup accuracy and couch deflection may be greater than scanners dedicated to radiotherapy. The full set of departmental commissioning and routine quality assurance tests applied to radiotherapy CT simulators must be carried out on the PET-CT scanner. CT image quality must be optimized for radiotherapy planning whilst understanding that the appearance will differ between scanners and may affect delineation. PET-CT quality assurance schedules will need to be added to and modified to incorporate radiotherapy quality assurance. Methods of working for radiotherapy and PET staff will change to take into account considerations of both parties. PET to CT alignment must be subject to quality control on a loaded and unloaded couch preferably using a suitable emission phantom, and tested throughout the whole data pathway. Data integrity must be tested throughout the whole pathway and a system included to verify that delineated structures are transferred correctly. Excellent multidisciplinary team communication and working is vital, and key staff members on both sides should be specifically dedicated to the project. Patient pathway should be clearly devised to optimize patient care and the resources of all departments. Recruitment of a cohort of patients into a methodology study is valuable to test the quality assurance methods and pathway.

Identification of C-terminal hydrophobic residues important for dimerization and all known functions of ParB of Pseudomonas aeruginosa

The ParB protein of Pseudomonas aeruginosa is important for growth, cell division, nucleoid segregation and different types of motility. To further understand its function we have demonstrated a vital role of the hydrophobic residues in the C terminus of ParB(P.a.). By in silico modelling of the C-terminal domain (amino acids 242-290) the hydrophobic residues L282, V285 and I289 (but not L286) are engaged in leucine-zipper-like structure formation, whereas the charged residues R290 and Q266 are implicated in forming a salt bridge involved in protein stabilization. Five parB mutant alleles were constructed and their functionality was defined in vivo and in vitro. In agreement with model predictions, the substitution L286A had no effect on mutant protein activities. Two ParBs with single substitutions L282A or V285A and deletions of two or seven C-terminal amino acids were impaired in both dimerization and DNA binding and were not able to silence genes adjacent to parS, suggesting that dimerization through the C terminus is a prerequisite for spreading on DNA. The defect in dimerization also correlated with loss of ability to interact with partner protein ParA. Reverse genetics demonstrated that a parB mutant producing ParB lacking the two C-terminal amino acids as well as mutants producing ParB with single substitution L282A or V285A had defects similar to those of a parB null mutant. Thus so far all the properties of ParB seem to depend on dimerization.

Confinement resonances in photoionization of Xe@C₆₀+

Experimental evidence is presented for confinement resonances associated with photoabsorption by a Xe atom in a C60 cage. The giant 4d resonance in photoionization of Xe is predicted to be redistributed into four components due to multipath interference of photoelectron waves reflected by the cage. The measurements were made in the photon energy range 60-150 eV by merging a beam of synchrotron radiation with a mass/charge selected Xe@C₆₀+ ion beam. The phenomenon was observed in the Xe@C(58)(3+) product ion channel. [corrected]

Variations in chondrocyte apoptosis may explain the increased prevalence of osteoarthritis in some joints

OBJECTIVES

To investigate whether there are any variations in chondrocyte susceptibility to an apoptotic stimulus between cells of articular cartilage (AC) from equine joints that differ in prevalence of osteoarthritis (OA).

METHODS

Cartilage from macroscopically normal equine metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints was used. Prior to culture, chondrocyte viability was assessed using the fluorescein diacetate (FDA) and propidium iodide paravital staining method. AC explants were subsequently treated with tumour necrosis factor-α (TNF-α) in combination with Actinomycin D to induce apoptosis. Apoptosis of chondrocytes in cartilage sections was assessed by expression of active caspase-3 using indirect immunohistochemistry and sections also histologically graded using a 'modified' Mankin scoring system.

RESULTS

Prior to culture (mean ± standard deviation) chondrocyte viability was 80.7% (3.5). The extent of chondrocyte apoptosis induced by TNF-α/Actinomycin D varied markedly according to the joint type that the cartilage was sampled from. For MCP joints, the extent of overall chondrocyte apoptosis was significantly higher (P < 0.001) in stimulated explants (26.7%, 10.3) than that observed in unstimulated control samples (9.6%, 7.5). Conversely, chondrocytes from PIP and DIP joint cartilage did not respond significantly to apoptotic stimulation (P > 0.05). Significant variations in cellularity and thickness were also evident between cartilages of different joint types.

CONCLUSIONS

Data in this study demonstrate that chondrocytes from three equine joint types with varying prevalences of OA differ significantly in terms of susceptibility to apoptosis induction. This may provide a possible explanation for the joint-specific nature of the disease.

ParB deficiency in Pseudomonas aeruginosa destabilizes the partner protein ParA and affects a variety of physiological parameters

Deletions leading to complete or partial removal of ParB were introduced into the Pseudomonas aeruginosa chromosome. Fluorescence microscopy of fixed cells showed that ParB mutants lacking the C-terminal domain or HTH motif formed multiple, less intense foci scattered irregularly, in contrast to the one to four ParB foci per cell symmetrically distributed in wild-type P. aeruginosa. All parB mutations affected both bacterial growth and swarming and swimming motilities, and increased the production of anucleate cells. Similar effects were observed after inactivation of parA of P. aeruginosa. As complete loss of ParA destabilized its partner ParB it was unclear deficiency of which protein is responsible for the mutant phenotypes. Analysis of four parB mutants showed that complete loss of ParB destabilized ParA whereas three mutants that retained the N-terminal 90 aa of ParB did not. As all four parB mutants demonstrate the same defects it can be concluded that either ParB, or ParA and ParB in combination, plays an important role in nucleoid distribution, growth and motility in P. aeruginosa.

External validation of serum hCG cutoff levels for prediction of resistance to single-agent chemotherapy in patients with persistent trophoblastic disease

Van Trommel et al have previously shown that serum human chorionic gonadotropin (hCG) cutoff levels can provide early prediction of resistance to first-line methotrexate (MTX) in patients with persistent trophoblastic disease (PTD). In this study, we validate this approach of prediction of resistance to single-agent chemotherapy in an independent and larger cohort of PTD patients using a different hCG assay. Receiver operating characteristics (ROC) curves were constructed to determine hCG cutoff levels and sensitivity between patients cured on single-agent chemotherapy (control group) and patients requiring change to combination chemotherapy (study group). Receiver operating characteristics analysis identified an hCG cutoff value of 737 IU l⁻¹ that enabled us to predict the subsequent development of single-agent chemotherapy resistance in 52% of patients before their fourth MTX course at 97.5% specificity. This would have enabled an earlier switch to combination chemotherapy reducing the MTX exposure by an average of 2.5 courses. The present findings confirm that serum hCG cutoff levels predict resistance to single-agent therapy earlier than traditional methods. Change to combination chemotherapy should be considered for patients whose serum hCG levels exceed these hCG cutoff values. For patients not exceeding the hCG cutoff levels, static or rising hCG levels should still be included in the criteria for change of chemotherapy.

Heparin-induced hyperkalemia

An 85-year-old lady with type 2 diabetes mellitus of 32 years duration with peripheral neuropathy was admitted under the vascular surgeons with extensive gangrene of her lower limb. She was on insulin for the last 7 years. Initial investigations showed normal serum electrolytes. She was started on antibiotics and unfractionated heparin, and her electrolytes showed hyperkalemia, which persisted on active treatment. Her short synacthen test showed good response, renin was normal with low aldosterone, urinary pH, sodium, potassium and osmolality was normal. On stopping heparin serum, potassium became normal. On restarting heparin (low molecular weight) during a suspected episode of pulmonary embolism, she developed hyperkalemia and heparin was stopped. Her potassium and aldosterone became normal on discontinuation of heparin. She developed hyperkalemia with both unfractionated and low molecular weight heparin.

Chondrocyte death by apoptosis is associated with cartilage matrix degradation

OBJECTIVES

To investigate the frequency of chondrocyte apoptosis in equine articular cartilage (AC) specimens and to examine the relationship between the process of cell death and the degree of cartilage degradation using a direct quantification of numbers of apoptotic cells and expression of active caspase-3.

METHODS

AC from equine metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints was used and each joint was graded macroscopically for cartilage degradation (macroscopic osteoarthritis (OA) score). Cartilage sections were graded using a 'modified' Mankin scoring system. Apoptosis of chondrocytes in cartilage sections was assessed morphologically by appearance of apoptotic features (direct method) and by expression of active caspase-3 using indirect immunohistochemistry.

RESULTS

The extent of apoptosis assessed by the direct method did not show any relationship with increasing severity of OA (P=0.72). However, there was a significant positive correlation between 'modified' Mankin score and apoptosis determined by caspase-3, with the extent of apoptosis found to increase linearly with increasing severity of OA (r=0.44, P=0.0043). Caspase-3 expression was found to be significantly higher in the superficial and middle zones than in the deep zone (P<0.001). In the superficial, middle and deep zones, expression of caspase-3 was significantly higher in the MCP joint than in the PIP joint (P=0.013, P=0.0018 and P=0.029, respectively). Within the MCP joints, apoptosis was higher in the lateral compartment compared to the medial (P=0.053).

CONCLUSIONS

The data presented in this study demonstrate that chondrocyte apoptosis is positively associated with degree of cartilage matrix damage and that the extent of apoptosis varies with cartilage zones and mechanical loading environment of the joint.

Transcription regulatory circuits in bacterial plasmids

Gene regulation circuits control all aspects of the life of plasmids. This review gives an overview of the current orchestration of the circuits that control plasmid replication, plasmid transfer, plasmid segregation and plasmid maintenance.

[Nah-plasmids of IncP-9 group from natural strains of Pseudomonas]

Use of polymerase chain reaction helped to establish that the most frequent among naphthalene utilizing bacteria, isolated on the territory of Belarus, are Nah-plasmids of IncP-9 incompatibility group and those with indefinite systematic belonging. With the help of classical test of incompatibility, restriction and sequence analyses three new subgroups within the IncP-9 group were discovered (zeta, eta and IncP-9-like replicons). Conducting of restriction analysis for amplification products of nahG and nahAc genes allowed us to reveal, in addition to known sequences of stated determinants, two new types of nahG gene. Restriction analysis performed on amplification products of 16S RNA genes (ARDRA method) showed that native hosts of Nah-plasmids of IncP-9 group are not only fluorescent bacteria from genus Pseudomonas (P. fluorescens, P. putida, P. aeruginosa, P. species), but also non-fluorescent bacteria with indefinite specific belonging.

The 64 508 bp IncP-1beta antibiotic multiresistance plasmid pB10 isolated from a waste-water treatment plant provides evidence for recombination between members of different branches of the IncP-1beta group

The complete 64508 bp nucleotide sequence of the IncP-1beta antibiotic-resistance plasmid pB10, which was isolated from a waste-water treatment plant in Germany and mediates resistance against the antimicrobial agents amoxicillin, streptomycin, sulfonamides and tetracycline and against mercury ions, was determined and analysed. A typical class 1 integron with completely conserved 5' and 3' segments is inserted between the tra and trb regions. The two mobile gene cassettes of this integron encode a beta-lactamase of the oxacillin-hydrolysing type (Oxa-2) and a gene product of unknown function (OrfE-like), respectively. The pB10-specific gene load present between the replication module (trfA1) and the origin of vegetative replication (oriV) is composed of four class II (Tn3 family) transposable elements: (i). a Tn501-like mercury-resistance (mer) transposon downstream of the trfA1 gene, (ii). a truncated derivative of the widespread streptomycin-resistance transposon Tn5393c, (iii). the insertion sequence element IS1071 and (iv). a Tn1721-like transposon that contains the tetracycline-resistance genes tetA and tetR. A very similar Tn501-like mer transposon is present in the same target site of the IncP-1beta degradative plasmid pJP4 and the IncP-1beta resistance plasmid R906, suggesting that pB10, R906 and pJP4 are derivatives of a common ancestor. Interestingly, large parts of the predicted pB10 restriction map, except for the tetracycline-resistance determinant, are identical to that of R906. It thus appears that plasmid pB10 acquired as many as five resistance genes via three transposons and one integron, which it may rapidly spread among bacterial populations given its high promiscuity. Comparison of the pB10 backbone DNA sequences with those of other sequenced IncP-1beta plasmids reveals a mosaic structure. While the conjugative transfer modules (trb and tra regions) and the replication module are very closely related to the corresponding segments of the IncP-1beta resistance plasmid R751 and even more similar to the IncP-1beta degradative plasmids pTSA and pADP-1, the stable inheritance operons klcAB-korC and kleAEF are most similar to those of the IncP-1beta resistance plasmid pB4, and clearly less similar to the other IncP-1beta plasmids. This suggests that IncP-1beta plasmids can undergo recombination in the environment, which may enhance plasmid diversity and bacterial adaptability.

Analysis of marker or complex chromosomal rearrangements present in pre- and post-natal karyotypes utilizing a combination of G-banding, spectral karyotyping and fluorescence in situ hybridization

The significance of complex chromosomal rearrangements presents a diagnostic dilemma. In the past, the use of G-banding coupled with fluorescence in situ hybridization (FISH) has been the standard approach. The recent development of spectral karyotyping (SKY) and multicolor FISH (M-FISH) has resulted in an increased accuracy of identification of marker or other complex chromosomal rearrangements. However, owing to the additional cost and time associated with SKY or M-FISH, and the restricted availability of such imaging facilities in many centers, it is not feasible to perform these procedures routinely on every sample. In addition, the identification of an aberration by SKY or M-FISH will often require confirmation by FISH. A practical approach is needed to take advantage of the complementary strengths of each method. In our center we utilize an algorithm that dictates the use of routine G-banding for the initial preliminary evaluation of a patient, followed by SKY characterization if marker chromosomes or complex translocations are detected by the G-banding analysis. According to this algorithm, FISH is used to verify the results once the origin of the abnormal chromosome has been determined by SKY. To demonstrate the effectiveness of this algorithm, we have analyzed both amniocyte and lymphocyte slides, using a combination of G-banding, SKY, and FISH. Our results confirm that an algorithm which selectively uses SKY or M-FISH will provide an efficient and improved method for pre- and post-natal chromosomal analysis.

Functional dissection of the ParB homologue (KorB) from IncP-1 plasmid RK2

Active partitioning of low-copy number plasmids requires two proteins belonging to the ParA and ParB families and a cis-acting site which ParB acts upon. Active separation of clusters of plasmid molecules to the defined locations in the cell before cell division ensures stable inheritance of the plasmids. The central control operon of IncP-1 plasmids codes for regulatory proteins involved in the global transcriptional control of operons for vegetative replication, stable maintenance and conjugative transfer. Two of these proteins, IncC and KorB, also play a role in active partitioning, as the ParA and ParB homologues, respectively. Here we describe mapping the regions in KorB responsible for four of its different functions: dimerisation, DNA binding, repression of transcription and interaction with IncC. For DNA binding, amino acids E151 to T218 are essential, while repression depends not only on DNA binding but, additionally, on the adjacent region amino acids T218 to R255. The C-terminus of KorB is the main dimerisation domain but a secondary oligomerisation region is located centrally in the region from amino acid I174 to T218. Using three different methods (potentiation of transcriptional repression, potentiation of DNA binding and activation in the yeast two-hybrid system) we identify this region as also responsible for interactions with IncC. This IncC-KorB contact differs in location from the ParA-ParB/SopA-SopB interactions in P1/F but is similar to these systems in lying close to a masked oligomerisation determinant.

Transposition patterns of unlinked transposed Ds elements from two T-DNA loci on tomato chromosomes 7 and 8

We have previously reported that unlinked transposed Ds elements originating from chromosome 4 of tomato preferentially inserted in chromosome 2. This observation, together with data from other studies, suggested that there may be absolute preferences for transposition, irrespective of the chromosomal location of the donor site. The aim of the present work was to verify whether the distribution of transposed Ds elements on chromosome 2 was non-random and thus whether, unlike the case in maize, unlinked transpositions in tomato are not distributed randomly. To do this, unlinked acceptor sites of Ds elements originating from two donor T-DNA loci lying on chromosomes 7 and 8 were mapped. Receptor sites for tr Ds elements transposed from the 1601D locus on chromosome 8 exhibited a non-random distribution (P<0.01). Eleven out of 46 independent transpositions mapped to chromosome 2 and, as this was statistically significant (P<0.01), proves that receptor sites for this element are not randomly distribution on the chromosomes. In addition, deviation of the observed number from the expected number of tr Dss was close to being significant for chromosome 4 (P=0.05-0.1). In contrast, the distribution of unlinked receptor sites for tr Dss derived from the 1481J locus on chromosome 7 was random. Chi(2)tests were performed for each chromosome, and for chromosome 4 the difference between the observed and the expected number of tr Dss was very high but statistically non-significant (P=0.05-0.1). For chromosome 2 the difference was statistically negligible. Therefore, we conclude that chromosome 2 does not serve as a preferential receptor for the transposition of Ds elements independently of the location of the donor site.

The bacterial ParA-ParB partitioning proteins

A pair of genes designated parA and parB are encoded by many low copy number plasmids and bacterial chromosomes. They work with one or more cis-acting sites termed centromere-like sequences to ensure better than random predivisional partitioning of the DNA molecule that encodes them. The centromere-like sequences nucleate binding of ParB and titrate sufficient protein to create foci, which are easily visible by immuno-fluorescence microscopy. These foci normally follow the plasmid or the chromosomal replication oriC complexes. ParA is a membrane-associated ATPase that is essential for this symmetric movement of the ParB foci. In Bacillus subtilis ParA oscillates from end to end of the cell as does MinD of E. coli, a relative of the ParA family. ParA may facilitate ParB movement along the inner surface of the cytoplasmic membrane to encounter and become tethered to the next replication zone. The ATP-bound form of ParA appears to adopt the conformation needed to drive partition. Hydrolysis to create ParA-ADP or free ParA appears to favour a form that is not located at the pole and binds to DNA rather than the partition complex. Definition of the protein domains needed for interaction with membranes and the conformational changes that occur on interaction with ATP/ADP will provide insights into the partitioning mechanism and possible targets for inhibitors of partitioning.

Homocysteine-lowering effect of 500 microg folic acid every other day versus 250 microg/day

BACKGROUND/AIMS

Elevated plasma total homocysteine (tHcy) concentrations are a risk factor for neural tube defects and vascular diseases. Supplementation with folic acid decreases tHcy. We investigated whether supplementation with 500 microg folic acid every other day is as effective in lowering tHcy as 250 microg folic acid each day.

METHODS

In a 4-week intervention study, 22 healthy young women (18-40 years old) took either 500 microg folic acid every other day (500-microg/2d group) or 250 microg folic acid each day (250-microg/d group). Fasting blood was collected on days 0 and 28.

RESULTS

Plasma folate concentrations increased by 11.4 nmol/l (6.8-15.9) in the 250-microg/d group and by 9.1 nmol/l (95% CI 1.9-16.3) in the 500-microg/2d group. These increases were not significantly different from each other. THcy concentrations decreased by 1.52 micromol/l (95% CI -2.09 to -0.95; p < 0.001) in the 250-microg/d group and by 0.88 micromol/l (-1.53 to -0.23; p < 0.05) in the 500-microg/2d group. The difference in decrease between the 250-microg/d group and the 500-microg/2d group was 0.64 micromol/l (p = 0.11).

CONCLUSION

Although not conclusive, this study suggests that supplying subjects with folic acid each day decreases tHcy more effectively than a double dose every other day.

Semen parameters, including WHO and strict criteria morphology, in a fertile and subfertile population: an effort towards standardization of in-vivo thresholds

In this study, the semen analysis results of a fertile population were compared with those from a subfertile population, in order to establish normal cut-off values for the standard semen parameters with the aid of receiver operating characteristic (ROC) curve analysis. The fertile group comprised healthy males (n = 107) without any history of fertility problems, the partners of whom had had a spontaneous pregnancy within one year of unprotected intercourse and were pregnant at the time of the male's inclusion into the study. A total of 103 males from couples attending the infertility clinic, and with an initial sperm count of <20x10(6)/ml were recruited to form the subfertile population. The best discriminating parameter between the two populations was sperm morphology evaluated according to WHO criteria at a cut-off point of 31% normal spermatozoa. The other cut-off values were at 8% for the acrosome index, 45% for motility, and 4% normal spermatozoa for strict criteria. Recalculating the ROC curve cut-off values based on an assumed 50% prevalence of subfertility in an assisted reproductive setting, the cut-off points were reduced to 21% and 3% normal spermatozoa for WHO and strict criteria respectively. For motility, the new cut-off value was at 20% motile spermatozoa, for motility quality at 3.5 (on a scale of 1-6), the acrosome index at 3% normal acrosomes, and the teratozoospermia index at 2.09.

Regulatory circuits for plasmid survival

Bacterial plasmids deploy a diverse range of regulatory mechanisms to control expression of the functions they need to survive in the host population. Understanding of the mechanisms by which autoregulatory circuits control plasmid survival functions, in particular plasmid replication, has been advanced by recent studies. At a molecular level, structural understanding of how certain antisense RNAs control replication and stability functions is almost complete. Control circuits linking plasmid transfer functions to the status of the bacterial population have been dissected, uncovering a complex and hierarchical organisation. Coordinate or global regulation of plasmid replication, transfer and stable maintenance functions is becoming apparent across a range of plasmid families.

Serum tumor markers: past, state of the art, and future

Serum determinations of tumor markers are indispensable in the diagnosis and management of cancer, and therefore play an important role in clinical practice. After a short historical survey, we systematically review a number of contemporary aspects of serum tumor markers related to various organ systems, and briefly indicate possible future developments.

Evaluation of remote stethoscopy for pediatric telecardiology

OBJECTIVE

To investigate the interobserver reliability and diagnostic validity of a commercial electronic stethoscope for pediatric telecardiology.

MATERIALS AND METHODS

Pairs of blinded pediatric cardiologists made independent diagnoses, recommendations concerning follow-up echocardiography, and specific judgments regarding heart sounds, murmurs, and congenital heart disease using an electronic (ES) or an acoustic (AS) stethoscope on 78 pediatric cardiology outpatients and at a distance of 450 km (280 miles) with 38 telemedicine cardiology outpatients. The kappa statistic (K) indexed the instruments' interexaminer reliabilities. The validity of ES was measured by K for ES versus AS and by the percentage of cases where the findings for ES and AS differed sufficiently to suggest an important ES screening error.

RESULTS

For heart disease, AS, ES, and tele-ES reliabilities were satisfactory (K = 0.80, 0.67, and 0.80, respectively), as were AS agreement with hands-on ES (K = 0.65) and with tele-ES (K = 0.64). The AS and ES reliabilities and ES/AS agreement were also satisfactory for systolic regurgitant and diastolic pulmonic murmurs (K = 0.63-0.78) but were unsatisfactory for evaluable heart sounds and other murmurs (K = 0.16-0.60). The ES yielded clinically important disagreements with AS in 5.4% of the clinic cases and 10.5% of the telemedicine cases (P = 0.67). In determining the need for additional work-up (echocardiography) or follow-up appointments, hands-on ES and tele-ES had a combined accuracy of 92%, with a sensitivity of 88% and a specificity of 97%.

CONCLUSIONS

Hands-on ES provided reliable and valid screening for congenital heart disease. Tele-ES was highly reliable but had reduced diagnostic validity. Examiner blinding, bandwidth limitations, and artificial restrictions on the remote assistant may have contributed to this reduced performance. As these factors are easily correctable, we regard the ES as a highly promising tool for pediatric telecardiology.

Bioavailability of folate from processed spinach in humans. Effect of food matrix and interaction with carotenoids

The effect of the food matrix and dietary fibre on the bioavailability of folate is not known. In a controlled, 3-week dietary intervention study, 28 men and 42 women were divided into six groups to receive either a control diet (n = 10), or the control diet plus 20 g/MJ per day (n = 12 per group) of whole-leaf spinach, minced spinach, liquefied spinach, or liquefied spinach to which dietary fibre (10 g/kg wet weight) was added. The sixth group received the control diet plus a synthetic carotenoid supplement with similar amounts of beta-carotene and lutein as found in spinach. A significantly higher plasma folate response was found for the pooled spinach groups than for the control group. Among the spinach groups no significant differences were detected. However, the plasma folate response of the pooled minced and liquefied spinach groups was greater than that of the whole-leaf spinach group (p = 0.03). Re-addition of dietary fibre to the liquefied spinach to compensate for the fibre broken down during liquefaction did not reduce the plasma folate response. The consumption of the carotenoid supplement did not have an effect on plasma folate concentrations compared with the control group. The food matrix in which the folate is entrapped plays a role in folate bioavailability.

Increased serum FSH in female fragile X premutation carriers with either regular menstrual cycles or on oral contraceptives

Fragile X premutations are known to be a risk factor for diminished ovarian function at a relatively young age. We studied endocrine profiles of female fragile X family members (n = 79) at risk of premature ovarian failure (POF). Of these 79 women aged <40 years, 45 had menstrual cycles, and 34 were using oral contraceptives. Of the women with menstrual cycles, the premutation carriers had higher serum FSH concentrations than women who were not carrying the premutation. Even premutation carriers with regular cycles showed increased serum FSH concentrations. Moreover, premutation carriers using oral contraceptives also demonstrated increased serum FSH concentrations. Irrespective of whether oral contraceptives were used, a serum FSH concentration of > or =15 IU/l was more common in the premutation carriers than in the other women. One premutation carrier using oral contraceptives had a serum FSH concentration of >40 IU/l, the threshold that defines POF. We confirmed that premutation carriers with menstrual cycles demonstrate premature ovarian dysfunction. However, we also found endocrine signs of unrecognized ovarian dysfunction in premutation carriers using oral contraceptives, despite endocrine alterations by oral contraceptives. Premutation carriers may have a poorer prognosis for future pregnancy, either achieved spontaneously or by assisted reproductive technology. We recommend that premutation carriers should be counselled not to wait too long if they wish to start a family.