Comparison of two methods for serotyping Campylobacter spp

Two serotyping schemes (Penner and Laboratory of Enteric Pathogens [LEP]) based on soluble heat-stable antigens were used to analyze 3,788 Campylobacter sp. isolates. A significant percentage (36.6%) was untypeable using LEP serotyping; greater cross-reaction was also observed. The relative discrimination capabilities of the techniques were similar. Penner serotyping fulfils more of the requisite criteria for typing methods.

Termination of pregnancy: patients' perceptions of care

BACKGROUND

Little is known about women's perceptions of care in termination of pregnancy (TOP). Developing an understanding of how care is experienced is crucial to improvements in services.

METHOD

Two hundred and eight women undergoing either a medical or surgical TOP reported on their perspectives of the experience and the care received. A mix of questionnaire and open questions analysed by content analysis was used. Women reported on the aspects which were most stressful, helped them to feel more relaxed, were unexpected in some way, and also on the provision of information and on the quality of staff care.

RESULTS

The most stressful aspects for the medical group related to the physical and emotional aspects of the process, whilst for the surgical group it concerned waiting in hospital for the operation. Whilst little was unexpected for the surgical group, many aspects came as a surprise to the medical group. Seeing the foetus was particularly difficult. All information provided was viewed as helpful, with greater information required about the phase following termination. Care from staff was rated positively, although areas for improvement in terms of opportunity to ask questions and ensuring concerns were dealt with were identified. Caring and non-judgemental staff attitudes were viewed as particularly important in helping women to feel as relaxed as possible in a potentially stressful situation.

CONCLUSION

Surgical termination schedules should avoid a long waiting time once the woman has been admitted. More adequate preparation is required for those having medical termination so that they have realistic expectations of what will happen, including the possibility of seeing the foetus. More attention to information about the time following termination, including possible emotional responses, is needed. The importance of positive staff attitudes in the quality of care is emphasised.

Identification of the exported proteins of the oral opportunistic pathogen Actinobacillus actinomycetemcomitans by using alkaline phosphatase fusions

A phoA fusion library of Actinobacillus actinomycetemcomitans genomic DNA has been screened to identify genes encoding exported and secreted proteins. A total of 8,000 colonies were screened, and 80 positive colonies were detected. From these, 48 genes were identified with (i) more than half having homology to known or hypothetical Haemophilus influenzae genes, (ii) 14 having no ascribed function, and (iii) 4 having very limited or no homology to known genes. The proteins encoded by these genes may, by virtue of their presence on the cell surface, be novel virulence determinants.

Social reasoning: a source of influence on aggression

Aggressive children show deficits and biases in their social information processing. Cognitions based on early experience and social schemas are also related to development and maintenance of aggressive behavior. Social reasoning can be linked to these aspects of social cognition, impacting on the situational cues individuals encode, their interpretations of events, and influencing response decisions. Past experience also influences development of social reasoning and social schema. Despite this, current discussion of the links between cognition and aggression rarely involves consideration of the influence of social reasoning. In this review, domain theory (E. Turiel, 1978, 1983) underpins an examination of links between social reasoning and aggression using empirical evidence drawn from research on the social reasoning of normal and aggressive children. Children as young as 3 appear to use consistent patterns of social reasoning when making judgments about transgressions and other social events, and these patterns are linked to social reasoning domains. We propose that aggressive children access information from the underlying social reasoning domains differently than their prosocial peers. This in turn affects their decision making and subsequent behavior in social situations. Our review explores developmental and clinical implications of the proposal and provides directions for future research.

Correlation between patients' satisfaction and objective measurement of knee stability after ACL reconstruction using a patellar tendon autograft

We evaluated the relationship between patients' satisfaction and objective measurements of knee stability after reconstruction of the ACL using a patellar tendon autograft. An examination of 59 patients 2-7 years after surgery was carried out. Assessment was made by the Knee and Osteoarthritis Outcome Score for patient satisfaction, a modified International Knee Documentation Committee form for clinical knee stability and a Telos stress radiography for PA stability. The results show that patients' satisfaction was much greater than the objective evaluation would suggest. We conclude that documenting mechanical knee stability alone is inadequate for follow-up studies and a questionnaire assessing patient satisfaction should be added.

What can we learn from interface pressure measurements?

Interface pressure measurements are imprecise and subject to many variables. When selecting pressure support systems, it is best to take these into account along with other important factors.

Sexually transmitted infections in primary care: a need for education

General practitioners and practice nurses require the clinical skills that will enable them to detect sexually transmitted infections in the context of a shift to having no, or insidious symptoms. They need to be able to confirm the diagnosis and have clear models for management and referral. Primary care and genitourinary medicine need to work more closely together to increase mutual understanding and clarify the issues which surround referral and attendance. Sexual health risk assessment through the investigation of sexual history is a helpful way forward in both differential diagnosis and in targeting sexual health promotion and care. Many aspects of these clinical skills are specific to the primary care context. There is a need for improved undergraduate, postgraduate, and in-service training. Multidisciplinary educational approaches are ideal for the subject of sexual health. Primary care groups offer a potential way forward to help develop quality in primary care and some are developing health improvement programmes that aim to address sexual health issues.

Colour Doppler diagnosis of perigraft flow following endovascular repair of abdominal aortic aneurysm

BACKGROUND

Endovascular repair of abdominal aortic aneurysm is a relatively new surgical technique which is less invasive than conventional open abdominal surgery but is associated with a significant specific complication of endoleak. The aim of this study was to determine the accuracy of duplex ultrasound imaging, utilising colour Doppler, as the primary method for post surgical monitoring of endovascular aneurysm repair.

METHODS

EXPERIMENTAL DESIGN

a case cohort study of 45 patients undergoing endovascular repair of abdominal aortic aneurysm.

SETTING

angiography, CT scanning and surgery performed at Westmead Hospital, a teaching hospital of the University of Sydney; patients followed postoperatively at the Westmead Vascular Laboratory, a dedicated vascular diagnostic ultrasound facility.

PATIENTS

Forty males and five females, mean age 69.1 years (range 51 to 84).

INTERVENTIONS

patients underwent attempted insertion of an EVT (endovascular prosthesis) for exclusion of abdominal aortic aneurysm (mean diameter 5.3 cm; range 4.0 to 8.4 cm). Conversion to open repair was required in three cases (6.6%). An aorto-biliac graft was inserted in 28 patients, a tube graft in eight and an aorto-unilateral iliac graft with femorofemoral (or ilioilial) crossover graft in six.

MEASURES

patients were followed over a period of 53 months (median follow-up time 15 months) with 106 colour Doppler scans of 39 endovascular grafts (mean of 2.9 scans per patient).

RESULTS

All aneurysms decreased in diameter (range 0.1 cm to 4.3 cm, mean 0.9 cm). Abnormal flow in the residual aneurysmal sac was found in three patients. In all three cases of endoleak the colour Doppler diagnosis was supported by CT scan and confirmed on angiography. The CT scans did not provide any additional information to that obtained by colour Doppler imaging.

CONCLUSIONS

Colour Doppler provides an effective means of non-invasive follow-up assessment of patients who have had endovascular repair of abdominal aortic aneurysms.

Demonstration of scrotal disease on bone scintigraphy

The identification of scrotal disease on a bone scan is reportedly rare. Most previous reports involve abnormally increased accumulation of radioisotope in the scrotal region. This article includes a compilation of three cases of incidental scrotal photopenic defects on bone scintigraphy and a brief review of the literature.

Do out-of-hours co-operatives improve general practitioners' health?

General practitioners (GPs) have been found to have a higher level of anxiety and depression then hospital managers and consultants. In 1995 and 1998, we surveyed GPs in Buckinghamshire. We found that the development of out-of-hours co-operatives was an important factor in the improvement in GPs' health status.

Therapeutic and physical fitness exercise prescription for older adults with joint disease: an evidence-based approach

Aging with joint disease does necessarily result in chronic pain, adoption of a sedentary lifestyle, and functional dependency. Several randomized controlled trials clearly show that regular exercise does not exacerbate pain or accelerate disease progression. On the contrary, these studies suggest that exercise training may increase the physiologic reserve and reduce the risk for functional dependency in older adults with joint disease. The goals for an exercise program should be directed toward increasing flexibility, muscle strength, endurance, and cardiovascular fitness. An exercise training program that is tailored specifically to an older adult's physical limitations may achieve these goals, and by optimizing patient safety lead to improve long-term exercise compliance.

Nitric oxide and cardiac autonomic control in humans

Cardiac autonomic control is of prognostic significance in cardiac disease, yet the control mechanisms of this system remain poorly defined. Animal data suggest that nitric oxide (NO) modulates cardiac autonomic control. We investigated the influence of NO on the baroreflex control of heart rate in healthy human subjects. In 26 healthy male volunteers (mean age, 23+/-5 years), we measured heart rate variability and baroreflex sensitivity during inhibition of endogenous NO production with N(G)-monomethyl-L-arginine (L-NMMA) (3 mg/kg per hour) and during exogenous NO donation with sodium nitroprusside (1 to 3 mg/h). Increases from baseline (Delta) in high-frequency (HF) indexes of heart rate variability were smaller with L-NMMA in comparison to an equipressor dose of the control vasoconstrictor phenylephrine (12 to 42 microg/kg per hour): Deltaroot mean square of successive RR interval differences (DeltaRMSSD)=23+/-32 versus 51+/-48 ms (P<0.002); Deltapercentage of successive RR interval differences >50 ms (DeltapNN50)=5+/-15% versus 14+/-12% (P<0.05); and DeltaHF normalized power=-2+/-7 versus 9+/-8 normalized units (P<0.01), respectively. Relative preservation of these indexes was observed during unloading of the baroreflex with sodium nitroprusside compared with a matched fall in blood pressure produced by a control vasodilator, hydralazine (9 to 18 mg/h): DeltaRMSSD=-8+/-8 versus -24+/-15 ms (P<0.001); DeltapNN50=-6+/-11% versus -15+/-19% (P<0.01); DeltaHF normalized power=-7+/-13 versus -13+/-11 normalized units (P<0.05), respectively. The change in cross-spectral alpha-index calculated as the square root of the ratio of RR interval power to systolic spectral power in the HF band (although not alpha-index calculated in the same way for the low-frequency bands or baroreflex sensitivity assessed by the phenylephrine bolus method) was attenuated with L-NMMA compared with phenylephrine (Delta=4+/-8 versus 14+/-15 ms/mm Hg, respectively; P<0.02) and with sodium nitroprusside compared with hydralazine (Delta=-7+/-6 and -9+/-7 ms/mm Hg, respectively; P<0.05). In conclusion, these data demonstrate that NO augments cardiac vagal control in humans.

Neutrophil function in pregnancy and rheumatoid arthritis

BACKGROUND

Pregnancy exerts suppressive effects on rheumatoid arthritis (RA). An attenuation in neutrophil function in late pregnancy which may explain this amelioration has previously been reported.

OBJECTIVE

A longitudinal investigation of neutrophil activity in healthy pregnant women (n=9) and pregnant patients with RA (n=9), compared with age matched non-pregnant patients with RA (n=12) and healthy controls (n=22).

METHODS

Neutrophil activation was measured in response to the physiological receptor agonists, n-formyl-methionyl-leucyl-phenylalanine (fMLP) and zymosan activated serum (ZAS). Superoxide anion production (respiratory burst) was determined by lucigenin enhanced chemiluminescence (LUCL); secondary granule lactoferrin release by enzyme linked immunosorbent assay (ELISA); and CD11b, CD18, and CD62L expression by flow cytometric analysis.

RESULTS

Stimulated neutrophil LUCL was significantly reduced in both pregnant women with RA and healthy pregnant women in the second (fMLP 43% and 69%, ZAS 43% and 59%, respectively) and third trimesters (fMLP 24% and 44%, ZAS 32% and 38%, respectively). Responses returned to normal within eight weeks of delivery and unstimulated levels remained unchanged throughout pregnancy. Basal and stimulated CD11b, CD18, and CD62L expression showed no variations throughout gestation for both pregnancy groups. Likewise, stimulated lactoferrin release and plasma lactoferrin remained unchanged. Certain morphological differences in RA neutrophils were highlighted by the flow cytometric analysis. Moreover, resting neutrophils and stimulated cells from patients with RA, including pregnant subjects, showed a marked increase in LUCL, but a reduction in CD11b, CD18, and CD62L. Low dose prednisolone and methylprednisolone had no effect on neutrophil parameters over the period of treatment with non-steroidal anti-inflammatory drugs.

CONCLUSION

The attenuation to neutrophil respiratory burst in both healthy and RA pregnancies may offer an explanation for the pregnancy induced remission of this inflammatory disorder.

Spiroplasma citri Surface Protein P89 Implicated in Adhesion to Cells of the Vector Circulifer tenellus

ABSTRACT Two microtiter plate assays were developed to study the adherence of the plant-pathogenic mollicute Spiroplasma citri to a monolayer of cultured cells of its leafhopper vector, Circulifer tenellus. Adherence was significantly reduced by prior treatment of the spiroplasmas with proteinase K or pronase. Electrophoresis and western blotting of spiroplasma membrane proteins, before and after exposure of intact spiroplasmas to proteases, revealed the concomitant reduction in intensity of a major membrane protein (P89) and a new polypeptide of approximately 46 kDa in protease-treated preparations (P46). Triton X-114 phase partitioning demonstrated that P89 and P46 are amphiphilic, and labeling of the new polypeptide P46 with anti-P89 serum suggested that this molecule may be a breakdown product of P89. Regeneration of P89 after proteinase K treatment of spiroplasmas was directly associated with restoration of the pathogen's attachment capability. Treatment of spiroplasmas with any of several carbohydrates and glycoconjugates or with tetramethyl-urea, a compound that interferes with hydrophobic associations, had a negligible effect on attachment. These results suggest that a spiroplasma surface protein, P89, has a role in S. citri adherence to C. tenellus cells.

Common elements of spiroplasma plectroviruses revealed by nucleotide sequence of SVTS2

DNA of SpV1-like spiroplasma plectroviruses (rods with single-stranded circular DNA) is scattered in the genome of the phytopathogen Spiroplasma citri and has significant consequences for evolution of the S. citri genome. We determined the complete nucleotide sequence of SVTS2, a SpV1-like virus of S. melliferum, a honeybee pathogen, to ascertain, by comparison with S. citri SpV1 viruses (GenBank U28974 and X51344), the defining features of this important group. The 6,824 nt DNA contains nine ORFs homologous to ORFs of S. citri SpV1 viruses and five ORFs unique to SVTS2. The predicted amino acid sequences of the homologous ORFs were 17-38% identical to those of their S. citri counterparts. The SVTS2 predicted ORF 1 product (Mr 47,031) was considerably smaller than those of known S. citri SpV1 viruses. Also, in contrast to those viruses, SVTS2 lacked an ORF with recognizable similarity to a transposase. ORF 2 of all three viruses had a homologue among the products of genes of MVL-1, a virus of Acholeplasma laidlawii, another plectrovirus. The results suggest that, at most, only slightly more than half of SpV1 genomes consists of genes shared by all spiroplasma viruses of the group.

The provision of leg ulcer services by practice nurses

As part of their implementation programme of leg ulcer guidelines, the group conducted a study of the caseload and attitudes and training of practice nurses with relation to leg ulcer management. They begin by outlining the prevalence and treatment methods of leg ulcers, then outline their study and put forward their resulting recommendations.

Implicit learning differences: a question of developmental level?

A. S. Reber's (1992) proposition that the implicit learning system should demonstrate invariance of intellectual level (IQ) was examined by comparing 20 children with intellectual disability (mean mental age [MA] = approximately 5.8 years) with 20 intellectually gifted children (mean MA = approximately 12.4 years) of similar chronological age (CA; approximately 9.5 years). Implicit learning was assessed using a task involving covariation of 2 incidental cues. Explicit learning was assessed using a task of similar logical structure. Contrary to the IQ-invariance proposition, implicit learning as well as explicit learning varied with intellectual level. A secondary aim was to distinguish the contributions of CA, IQ, and MA to implicit learning. This was done by combining the samples of children in the present study with 2 samples of younger and older children of average ability from a study by M. Maybery, M. Taylor, and A. O'Brien-Malone (1995). Analyses showed that MA is critical to implicit learning.

Implicit learning differences: a question of developmental level?

A. S. Reber's (1992) proposition that the implicit learning system should demonstrate invariance of intellectual level (IQ) was examined by comparing 20 children with intellectual disability (mean mental age [MA] = approximately 5.8 years) with 20 intellectually gifted children (mean MA = approximately 12.4 years) of similar chronological age (CA; approximately 9.5 years). Implicit learning was assessed using a task involving covariation of 2 incidental cues. Explicit learning was assessed using a task of similar logical structure. Contrary to the IQ-invariance proposition, implicit learning as well as explicit learning varied with intellectual level. A secondary aim was to distinguish the contributions of CA, IQ, and MA to implicit learning. This was done by combining the samples of children in the present study with 2 samples of younger and older children of average ability from a study by M. Maybery, M. Taylor, and A. O'Brien-Malone (1995). Analyses showed that MA is critical to implicit learning.

Spiroplasma citri Movement into the Intestines and Salivary Glands of Its Leafhopper Vector, Circulifer tenellus

ABSTRACT Spiroplasma citri, a helical, wall-less prokaryote in the class Molli-cutes, is transmitted by the beet leafhopper, Circulifer tenellus. Invasion of leafhopper tissues and cytopathological effects by S. citri were investigated by transmission electron microscopy. All eight cell types of the principle salivary glands, as well as the adjacent muscle cells and the cells of the accessory salivary glands, were colonized by the spiroplas-mas. In both midgut epithelia and salivary gland cells, spiroplasmas usually occurred in membrane-bound cytoplasmic vesicles that often were located near the cell periphery. In several salivary gland cells, spiroplas-mas were also observed within membranous pockets apparently formed by invagination of the plasmalemma beneath intact basal lamina. These observations are consistent with spiroplasma entry into the insect cells by receptor-mediated endocytosis. Cytopathological effects of spiroplasma infection in salivary cells included loss of membrane and basal lamina integrity, presence in some cells of irregular inclusion-like structures containing dense matrices of filamentous material that labeled with anti S. citri antibodies, and apparent disorganization of the endoplasmic reticulum. Compared to the tightly aligned fiber bundles in healthy muscle cells, bundles in spiroplasma-containing muscle cells appeared fragmented and loosely arranged. Such symptoms could contribute to the reduction in longevity and fecundity that has been previously reported for S. citri-infected C. tenellus.

Use of opposing reflex stimuli and heart rate variability to examine the effects of lipophilic and hydrophilic beta-blockers on human cardiac vagal control

Evidence from animal studies suggests that beta-blockers can act within the central nervous system to increase cardiac vagal motoneuron activity. We have attempted to determine whether such an effect is evident in healthy humans, by examining the effects of lipophilic and hydrophilic agents on heart rate variability and cardiac vagal reflexes. A total of 20 healthy volunteers took part in the study. Autonomic studies were performed after 72 h of treatment with placebo, atenolol or metoprolol in a blinded cross-over design. ECG recordings were taken at rest and during mental and orthostatic stress. Heart rate variability was measured in the time and frequency domains. The effects on heart rate of two opposing cardiac vagal reflexes were examined. Trigeminal stimulation causing vagal stimulation, and isometric forearm muscle contraction ('muscle heart reflex') causing vagal inhibition, were performed alone and simultaneously. At rest, during mental stress and during trigeminal stimulation, beta-blocker therapy was associated with significantly increased high-frequency beat-to-beat heart rate variability when compared with placebo. There were no significant differences in effects on heart rate or heart rate variability between atenolol and metoprolol. Analysis of the muscle heart reflex, alone and with simultaneous trigeminal stimulation, showed that the magnitude of the R-R interval response was significantly greater after beta-blocker therapy compared with placebo, but the effects of atenolol and metoprolol were equivalent. beta-Blocker therapy increased cardiac vagal activity, as shown by measures of high-frequency heart rate variability and reflex studies. Lipophilic and hydrophilic beta-blockers appeared to be equally efficacious in increasing the cardiac vagal modulation of heart rate.

Role of p38 in the priming of human neutrophils by peritoneal dialysis effluent

Peritoneal dialysis effluent (PDE) contains a low-molecular-weight substance that is able to prime human neutrophils for the release of arachidonic acid and superoxide anion. Conventional priming agents, such as tumor necrosis factor alpha (TNF-alpha), are known to signal via mitogen-activated protein (MAP) kinases; at least one possible substrate for MAP kinases is cytosolic phospholipase A(2) (cPLA(2)). Phosphorylation of this enzyme results in arachidonic acid release, and this fatty acid is a potent primer and activator of the human neutrophil NADPH oxidase. Because of the striking similarities between the priming of neutrophils with agents such as TNF-alpha and PDE, we have investigated the signalling pathways evoked by PDE and explored the possibility that cPLA(2) is a target for activated MAP kinases. Our results show that PDE treatment of human neutrophils results in the phosphorylation of the p38 kinase rather than the p42 and p44 kinases. Phosphorylation of p38 is transient with maximal activity being observed 1 min after exposure to PDE. We were unable to demonstrate that activation of p38 resulted in phosphorylation of cPLA(2); furthermore, translocation of this enzyme to a membrane-containing fraction was not enhanced in PDE-treated neutrophils. Taken together, these data suggest that, in a manner similar to that of TNF-alpha, PDE primes human neutrophils by the activation of the p38 kinase. However, unlike the cytokine, the activation of this protein does not result in phosphorylation or activation of cPLA(2).

Mechanisms of spiroplasma genome variation associated with SpV1-like viral DNA inferred from sequence comparisons

Genomes of Spiroplasma citri strains have rearranged frequently during their evolution, partly due to multiple integrated sequences of spiroplasma viruses. To understand better the role of viral sequences in genome evolution, we examined available nucleotide sequences of viruslike elements in the S. citri chromosome. Comparison of integrated and nonintegrated sequences of spiroplasma virus SpV1-C74 DNA suggested that it is an encapsidated form of the circular transposition intermediate belonging to an insertion sequence (IS3) family member. One SpV1-C74 viral DNA fragment was identified as interrupting the remains of a DNA adenine modification methylase gene. A viral DNA insertion of SpV1-R8A2 B DNA had hallmarks of having suffered an internal deletion by a site-specific recombination system. Homologous recombination likely was responsible for several deletions within viral DNA. A homologous recombination event was inferred between part of a viral DNA insertion and a similar chromosomal sequence. Dispersed sequences from SpV1-like C4 open reading frames (ORFs) were identified as involved in a complex deletion-inversion event. Thus, SpV1-like sequences likely have altered spiroplasma genomes by inserting within active genes, destroying their function, by providing targets for site-specific recombination, by mediating deletions of sequences adjacent to their integration sites, and by providing targets for homologous recombination, leading to inversions.

Malignant fibrous histiocytoma of the trachea

Primary tracheal sarcomas are rare. Only 23 cases have previously been reported in the English literature. The present case describes a 72-year-old woman with a malignant fibrous histiocytoma of the trachea. She underwent an endoscopic resection followed by radiotherapy and is well at 12 months follow up. Other cases are reviewed. Tracheal resection is the standard care. However, local resection with postoperative radiotherapy remains an option. Adjuvant chemotherapy may improve local control. Long-term survival has been documented.

Neutrophil function in women with pre-eclampsia

OBJECTIVE

To investigate the function of neutrophils in normal pregnancy and pre-eclampsia.

DESIGN

Baseline levels and activated responses of peripheral blood neutrophils were measured in response to the physiological agonists, n-formyl-met-leu-phe (fMLP) and zymosan activated serum.

SAMPLE

Neutrophils of 16 pre-eclamptic, 17 normal pregnant (third trimester) and 15 nonpregnant age-matched control women were calculated.

SETTING

Antenatal Clinic, City Hospital, Nottingham.

METHODS

Neutrophil superoxide anion production was determined by lucigenin-enhanced chemiluminescence; the release of secondary granule lactoferrin by ELISA; and the expression of cell surface adhesion molecules CD11b, CD18 and L-selectin (CD62L) by flow cytometric analysis.

RESULTS

Superoxide anion generation was reduced in the pregnant group compared with nonpregnant controls [fMLP by 51% (P = 0.03) and zymosan activated serum by 56% (P = 0.01)] but pre-eclamptic measurements did not show a similar reduction. There were no differences between the three study groups in the plasma levels of lactoferrin, or in the stimulated expression and release of CD11b and CD18, or lactoferrin and L-selectin. The base-line levels for the production of superoxide anions; the expression of CD11b or CD18 or L-selectin; and the release of lactoferrin showed no significant differences.

CONCLUSIONS

Circulating neutrophils in pregnancy and pre-eclampsia are neither activated nor primed in vivo, however the release of reactive oxygen species is diminished in normal pregnancy. In comparison, an elevation of reactive oxygen generation in pre-eclampsia may highlight a role for neutrophils in the oxidative stress and pathophysiology of this disease.

Significance of fatty acids in pregnancy-induced immunosuppression

Pregnancy can exert suppressive effects on chronic inflammatory conditions. We have previously demonstrated a depression in polymorphonuclear leukocyte (PMN) respiratory burst during pregnancy which could explain this amelioration. To elucidate the biochemical mechanism, we have examined PMN phospholipase A2 (PLA2) activity and its relationship to cellular and circulating fatty acids in pregnant women (30 to 34 weeks) and nonpregnant controls. PMN PLA2 activity was determined by arachidonic acid (AA) and leukotriene B4 (LTB4) release, respiratory burst activity was determined by lucigenin-enhanced chemiluminescence, and total serum and PMN fatty acid levels were determined by gas-liquid chromatography. AA release was significantly reduced for pregnancy PMNs in response to N-formyl-met-leu-phe (fMLP) under unprimed and tumor necrosis factor alpha (TNF-alpha)- or interleukin 8-primed conditions. Similarly, LTB4 liberation was significantly reduced in response to fMLP and phorbol myristate acetate in unprimed and TNF-alpha-primed pregnancy PMNs. All major fatty acid classes were altered in the pregnant state. Of these differences in PMNs, oleic acid and alpha-linolenic acid showed a significant increase (13 and 26%, respectively) and stearic acid and AA showed a significant decrease (8 and 30%, respectively). The stearic acid, oleic acid, and AA compositions of all cells analyzed correlated with their corresponding changes in serum fatty acid levels. Crossover serum incubations modified both fatty acid profiles and the PMN respiratory burst accordingly, while individual fatty acid incorporation studies highlighted the importance of polyunsaturated fatty acids for NADPH oxidase efficiency. These findings indicate that the attenuation of PMN function in pregnancy may originate from a reduction in the available pool of cellular fatty acids. Furthermore, this reduction arises as a direct result of a pregnancy-induced shift in circulating fatty acids from polyunsaturated to monounsaturated forms.

A practical approach to dressing wounds in difficult positions

Despite the availability of an increasing number of innovative dressing products, many patients' wounds remain a challenge to dress in practice. However, the creative use of widely available products and other resources can help to address some of the difficulties that are regularly encountered. If different sizes of dressing (to allow for cutting and shaping) or more innovatively shaped products (which may be more expensive per item) are used, this can result in a better dressing fit and therefore increase product wear time which is both clinically effective and cost-effective. When a good solution is found for dealing with certain wound types then great benefit can be gained from publishing the information to prevent others from struggling to overcome the same difficulties.

Yellow Vine of Watermelon and Pumpkin in Tennesse

Yellow vine (YV) is a recently recognized decline of cucurbits expressed as plant yellowing, phloem discoloration, and death of vines as fruit approach maturity. In severely affected fields, YV incidence can range from 50 to 100% with similar yield loss. The disease has been associated with a phloem-limited, walled bacterium belonging to the gamma-3-proteobacteria (1), for which specific polymerase chain reaction (PCR) primers have been developed and used in diagnosis (2). First observed in 1988 in Oklahoma and Texas squash and pumpkin, YV was not detected in watermelon and cantaloupe until 1991. The disease has never been detected in cucumber. Efforts to date have been unsuccessful in transmitting the disease with dodder, grafting, or selected insects. Initially, the geographic range of the disease appeared to be generally confined to central and northeastern Oklahoma and north central Texas, an area known as the Cross Timbers Region. In 1997 to 1998, YV was diagnosed in commercial fields of watermelon and muskmelon from east Texas (Post Oak Savannah) and all cucurbit-growing areas of Oklahoma. In late summer 1998, symptoms similar to those of YV were observed in one watermelon (Hardeman County) and three pumpkin (Rhea and Morgan counties) fields in Tennessee where the leaves turned yellow and chlorotic and affected plants exhibited phloem discoloration. Estimated incidence of YV ranged from less than 1 to 20% of the plants in affected fields. PCR, with the YV-specific primers (2), amplified a band of the expected size (409 bp) from all watermelon and pumpkin plants exhibiting phloem discoloration. In contrast, no bands were amplified from asymptomatic (no phloem discoloration) watermelon or pumpkin. The nucleotide sequence of the DNA fragment amplified from a Tennessee watermelon and pumpkin plant was identical to that of the YV bacterium. The occurrence of YV outside of the Cross Timbers Region, and in a location as distant as Tennessee, suggests that the disease may be much more widespread than previously recognized. Diagnosis and monitoring of YV in all cucurbit-growing areas is critical for determining the geographic distribution and losses caused by this emerging disease. References: (1) F. J. Avila et al. Phytopathology 88:428, 1998. (2) U. Melcher et al. (Abstr.) Phytopathology. 89(suppl.):S95, 1999.

The cost of MRI: changes in costs 1989-1996

A study was conducted to provide an up-to-date analysis of the costs associated with operating an MRI facility in a mainstream National Health Service (NHS) setting. This paper presents an analysis of the costs associated with the acquisition and operation of an MRI scanner installed at the Walsgrave NHS Trust in Coventry in 1988. Costs arising immediately after the introduction of the MRI facility in 1988 are compared with the costs arising towards the end of the scanner's useful life during the 1995/96 financial year. The findings suggest that although the nominal total costs of MRI have increased marginally, from 403,223 Pounds to 434,037 Pounds (an increase of 30,814 Pounds), the increase in total costs is below the rate of inflation, and the nominal average costs of MRI have fallen from 179.20 Pounds to 115.77 Pounds over the period.

The phytopathogenic mollicute-insect vector interface: a closer look

ABSTRACT Spiroplasma citri, transmitted by phloem-feeding leafhoppers, moves from the gut lumen through the gut wall, hemolymph, and salivary glands and multiplies in insect tissues. Nontransmissible lines were deficient in their ability to cross these barriers. Molecular analysis revealed extensive chromosomal rearrangements between the transmissible and nontransmissible spiroplasma lines including a large chromosomal inversion and deletions of about 10 kb at each inversion border. One open reading frame of the deleted region, cloned from the transmissible strain BR3-3X, encodes an integral membrane protein of 58 kDa that shares limited sequence similarity with major adhesin proteins of two zoopathogenic mycoplasmas. Adhesion of spiroplasmas to cultured leafhopper cells was inhibited by proteases, suggesting that adherence to host cells is mediated by spiroplasma membrane protein(s). A hypothetical model for insect transmission of phytopathogenic mollicutes is presented.

A comparison of medical and surgical termination of pregnancy: choice, emotional impact and satisfaction with care

OBJECTIVE

To investigate whether women having medical or surgical terminations of pregnancy differ in their emotional distress before or after the procedure. To evaluate whether choice of procedure occurs, the factors influencing type of procedure and the effect of choice on emotional responses and satisfaction with care.

DESIGN

A prospective comparative study.

SETTING

A termination of pregnancy unit in a University Teaching Hospital.

PARTICIPANTS

Two hundred and seventy-five women attending for medical or surgical first trimester termination of pregnancy.

METHODS

Interviews concerning choice and measures of emotional status were completed prior to terminations. Four weeks after termination emotional functioning was reassessed together with satisfaction with care.

RESULTS

Women having a surgical termination waited longer for the procedure and were at more advanced gestation than those having the medical termination. There were no differences in emotional responses related to type of procedure or gestation. One-quarter remained highly anxious at four weeks. Medical and surgical groups did not differ in emotional status prior to termination. Those having the medical procedure rated it as marginally more stressful and experienced more post-termination physical problems and disruption to life. Seeing the fetus was associated with more intrusive events (nightmares, flashbacks, unwanted thoughts related to the experience). One-quarter of the medical and 67% of the surgical group reported having no choice in type of procedure. Only 53% of the medical group would choose the same procedure again compared with 77% of the surgical group.

CONCLUSIONS

Termination method did not influence emotional adjustment. Many women were not offered genuine choice of procedure. Having choice was considered very important but was unrelated to emotional distress or satisfaction with care.

Effects of r-metHuG-CSF on polymorphonuclear leucocyte kinetics and function in patients on continuous ambulatory peritoneal dialysis

End-stage renal failure (ESRF) patients undergoing continuous ambulatory peritoneal dialysis (CAPD) are immunocompromised and exhibit abnormal circulating polymorphonuclear leucocyte (PMN) function, including reduced phagocytosis and intracellular killing. Six uraemic patients on CAPD were each given 300 microg granulocyte colony stimulating factor (G-CSF) every day for 5 d and PMN function tests were performed daily. By day 5 of the study CD11b expression was significantly decreased in response to N-formylmethionylleucylphenylalanine (fMLP) and opsonized Staphylococcus epidermidis stimulation, and expression of L-selectin (CD62L) was significantly decreased in response to opsonized Staphylococcus epidermidis stimulation. Further, superoxide anion production and Fc gammaRI (CD64) expression were found to be significantly increased and Fc gammaRII (CD16) expression was lowered. Circulating white cell and PMN counts were significantly elevated in response to treatment. Administration of G-CSF did not appear to have corrected the abnormalities in phagocytosis and intracellular killing. This study suggests that G-CSF does no harm to ESRF patients and influences uraemic PMN function in a manner that is comparable to its effects on PMN in non-uraemic subjects.

The role of the endogenous anti-inflammatory compound gravidin in pre-eclampsia

OBJECTIVES

The study's aims were to investigate the levels of gravidin, an endogenous phospholipase A2 inhibitor, in pregnancy and pre-eclampsia and to establish its effects on neutrophil function.

STUDY DESIGN

Serum samples were collected from 9 nonpregnant, 15 preeclamptic, and 10 healthy pregnant women and assayed for free gravidin by enzyme-linked immunosorbent assay. Neutrophil phospholipase A2 and respiratory burst activities were determined in the presence of isolated free gravidin by cellular arachidonic acid release and superoxide anion production.

RESULTS

Levels of free gravidin were higher in the healthy pregnant (36.1 +/- 5.5 ng/mL) and preeclamptic (17.8 +/- 2.8 ng/mL) groups than in the nonpregnant control group (3.9 +/- 0.5 ng/mL) and were significantly different between pregnancy groups (P <.01, Mann-Whitney U test). Free gravidin caused a concentration dependent decrease in N-formyl-methionyl-leucyl-phenylalanine-stimulated neutrophil arachidonic acid release (inhibitory concentration of 50% 25 nmol/L) and superoxide anion generation (inhibitory concentration of 50% 32 nmol/L).

CONCLUSIONS

Circulating levels of free gravidin are reduced in pre-eclampsia compared with normal pregnancy. This may encourage an increase in the respiratory burst of neutrophils in pre-eclampsia and could contribute to the oxidative stress and vascular damage that characterize this disease.

Prognostic factors affecting disease-free survival in patients with Hodgkin's disease stages IA and IIA treated initially with radiotherapy alone in a single centre during 1973 to 1992

One hundred forty-nine patients with either stage IA (90 patients) or stage IIA (59 patients) Hodgkin's disease (HD) received radiotherapy alone as their first line treatment. Only stage of the nine factors selected for Cox multivariate analysis was of prognostic significance. Patients with grade 1 nodular sclerosing HD did not have a significantly better disease-free survival than those with grade 2 disease.

Development and use of an established cell line of the leafhopper Circulifer tenellus to characterize Spiroplasma citri-vector interactions

A continuous cell line of embryonic origin from the leafhopper Circulifer tenellus, CT 1, was established using a protocol modified from thrips cell culture. The line was used to develop an in vitro model to examine the mode of entry of the plant pathogenic mollicute Spiroplasma citri into insect host cells. Confluent monolayers were achieved in 5-6 months using a simple medium developed for maintaining established leafhopper cell lines. The newly established CT 1 line, and that of another leafhopper, Nephotettix cincticeps, were exposed to S. citri and examined by electron microscopy. S. citri was found to cytadhere and to be present in apparent invaginations of the host cell membranes of cell lines of both leafhopper species, supporting the hypothesis that this pathogen enters its insect host via endocytosis.

Role of arachidonic acid and its metabolites in the priming of NADPH oxidase in human polymorphonuclear leukocytes by peritoneal dialysis effluent

Peritoneal dialysis effluent (PDE) contains a low-molecular-weight solute that will activate and prime the NADPH oxidase of human neutrophils via a phospholipase A2 (PLA2)-dependent mechanism. Since the products of PLA2 are known to activate and prime the oxidase we have investigated their role in the dialysis effluent-mediated activation and priming of human neutrophils. NADPH oxidase activity of PDE-primed and -unprimed neutrophils was measured by lucigenin-enhanced chemiluminescence in the presence of known inhibitors of the arachidonic acid cascade. Incubation of neutrophils with the nonselective PLA2 inhibitor quinacrine (0 to 100 microM) reduced oxidase activity in both primed and unprimed cells. Furthermore, primed cells were more sensitive to the action of quinacrine than were unprimed cells. We were unable to determine the relative roles of secretory PLA2 (sPLA2) and cytosolic PLA2 (cPLA2) since the selective sPLA2 inhibitor scalaradial (0 to 100 microM) inhibited oxidase activity in both groups of cells by similar degrees, while the specific cPLA2 inhibitor AACO-CF3 (0 to 50 microM) failed to affect activity in either group. Inhibition of platelet-activating factor (PAF), cycloxygenase, and 5-lipoxygenase-activating protein by hexanolamino-PAF (0 to 25 microM), flurbiprofen (0 to 25 microM), and MK886 (0 to 5 microM), respectively, had no effect upon oxidase activity. However, the direct inhibition of 5-lipoxygenase by caffeic acid or lipoxin A4 resulted in a similar concentration-dependent attenuation of oxidase activity in both primed and unprimed cells. Leukotriene B4 (LTB4) release from primed neutrophils was comparable to that from unprimed cells with the exception of phorbol myristate acetate-stimulated cells, which released fivefold more LTB4 than control. Taken together, these results suggest that it is arachidonic acid per se, and not its metabolites, that is important in priming of the neutrophil NADPH oxidase by dialysis effluent.