Reintroducing a keystone bioturbator can facilitate microbial bioremediation in urban polluted sediments

Anthropogenic environmental stressors have significantly reduced biodiversity and the capacity of remnant natural habitats to deliver ecosystem functions and services in urban areas. To mitigate these impacts and recover biodiversity and function, ecological restoration strategies are needed. While habitat restoration is proliferating in rural and peri-urban areas, strategies purposely designed to succeed under the environmental, social and political pressures of urban areas are lacking. Here, we propose that ecosystem health in marine urban areas can be improved by restoring biodiversity to the most dominant habitat, unvegetated sediments. We reintroduced a native ecosystem engineer, the sediment bioturbating worm Diopatra aciculata, and assessed their effects on microbial biodiversity and function. Results showed that worms can affect the diversity of microbes, but effects varied between locations. Worms caused shifts in microbial community composition and function at all locations. Specifically, the abundance of microbes capable of chlorophyll production (i.e. benthic microalgae) increased and the abundance of microbes capable of methane production decreased. Moreover, worms increased the abundances of microbes capable of denitrification in the site with lowest sediment oxygenation. Worms also affected microbes capable of degrading the polycyclic aromatic hydrocarbon toluene, although the direction of that effect was site-specific. This study provides evidence that a simple intervention such as the reintroduction of a single species can enhance sediment functions important for the amelioration of contamination and eutrophication, although further studies are needed to understand the variation in outcomes between sites. Nevertheless, restoration strategies targeting unvegetated sediments provide an opportunity to combat anthropogenic stressors in urban ecosystems and may be used for precondition before more traditional forms of habitat restoration such as seagrass, mangrove and shellfish restoration.

Valsartan exposure in pregnancy with resultant anhydramnios and chronic kidney disease in a late preterm infant

In utero exposure to angiotensin II receptor blockers (ARBs) has fetotoxic effects including renal failure, oligohydramnios and lung hypoplasia. We present the case of a 24-year-old woman who presented to the maternity services in the 34th week of her first pregnancy. She was taking valsartan for hypertension. Ultrasound showed a structurally normal fetus with anhydramnios. The patient was admitted and valsartan was discontinued. She had spontaneous preterm delivery at 35 weeks' gestation of a baby girl. The baby's urine output was minimal in the first week of life and she was transferred to a paediatric hospital for specialist nephrology input. At 6 months of age, she requires ongoing nephrology follow-up and she remains on treatment for hypertension and anaemia. This case demonstrates the serious adverse effects resulting from ARB exposure in utero, and highlights the importance of avoiding fetotoxic medications in women of childbearing age.

Investigating the Test of Premorbid Functioning (TOPF) in predicting Wechsler Abbreviated Scale of Intelligence - Second edition (WASI-II) scores in an Australian sample

Accurate prediction of premorbid functioning is important in neuropsychological assessment. We aimed to investigate the predictive accuracy of the TOPF and examine this word list at an item level against WASI-II scores, using Australian pronunciations. The sample of 219 healthy Australians were aged 18-82 years. Multiple regression analyses were used to replicate the TOPF and simple demographic models based on the US TOPF standardization. Rasch analyses provided a comparison of Australian, US and UK word order from the proportion of words pronounced correctly. The variance explained in WASI-II index scores ranged from R²=.12 (PRI) to .33 (FSIQ-2), which was approximately half that reported in the US standardization study. The accuracy of predicted WASI-II scores was also slightly less in our sample. Thirty-two words were out of place by five places or more compared with the US word order and 30 compared with the UK. These results add to concerns about the application the TOPF with norms developed in the US and UK in the Australian context. Clinicians are advised not to apply the five error discontinue rule when using the TOPF in the local context. Development of a more accurate word reading task for use in Australia is warranted.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species

BACKGROUND

Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests.

RESULTS

We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes.

CONCLUSIONS

The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant.

Systematic review and meta-analysis of thermal ablation versus surgical nephrectomy for small renal tumours

PURPOSE

A systematic review was undertaken to provide a meta-analysis of clinical trials comparing thermal ablation with surgical nephrectomy for small renal tumours.

METHODS

PubMed (MEDLINE), EMBASE, AMED, and Scopus were searched in August 2013 for eligible prospective or retrospective comparative trials following the PRISMA selection process. Thermal ablation was compared with surgical nephrectomy. Quality of included studies was assessed on the Newcastle-Ottawa Scale (NOS). The primary endpoint was disease-free survival and was analyzed on the log-hazard scale. Secondary outcome measures included complications, local recurrence, and decline of renal function. Hazard ratios (HR) and risk ratios (RR) were calculated with a random effects model, and meta-regression analysis was performed to explore clinical heterogeneity.

RESULTS

Six clinical trials (1 randomized and 5 cohort; 6-8 stars on the NOS scale) involving 587 patients with small renal tumors (mean size 2.5 cm) treated with either thermal ablation (percutaneous or laparoscopic application of radiofrequency or microwave) or surgical nephrectomy (open or laparoscopic) were analyzed. Overall complication rate was significantly lower in the ablation group (7.4 vs. 11%; RR: 0.55, 95% confidence interval [CI]: 0.31-0.97, p = 0.04). Postoperative decline of eGFR was higher in case of nephrectomy (mean difference: -14.6 ml/min/1.73 m(2), 95% CI: -27.96 to -1.23, p = 0.03). Local recurrence rate was the same in both groups (3.6 vs. 3.6%; RR: 0.92, 95% CI: 0.4-2.14, p = 0.79) and disease-free survival also was similar up to 5 years (HR: 1.04, 95% CI: 0.48-2.24, p = 0.92).

CONCLUSIONS

Thermal ablation of small renal masses produces oncologic outcomes similar to surgical nephrectomy and is associated with significantly lower overall complication rates and a significantly less decline of renal function. More randomized, controlled trials are necessary.

Prevalence and predictors of abdominal aortic calcification in healthy living kidney donors

BACKGROUND

Vascular calcification (VC) is common and is both a marker and a cause of increased cardiovascular morbidity and mortality, especially so in chronic kidney disease (CKD) patients. Renal transplantation is the cornerstone of the successful long-term management of CKD, and in order to satisfy transplantation needs, more use is made now of living kidney donors (LKD). Prior to selection for transplantation, much screening of potential LKD takes place, including for cardiovascular issues. It is not known; however, how much these potentially healthy LKD may be prone to clinically silent VC.

METHODS

We identified 103 living kidney donors from 2011 renal transplant records. Abdominal aortic calcification (AAC) was assessed using existing abdominal CT imaging using multi-channel CT aortograms (used primarily to assess renal vascular anatomy). Using these CT scans, manual calcium scoring was undertaken to calculate total aortic calcium load (AAC severity score). The prevalence, severity and associations of AAC between calcified and non-calcified donors were then compared.

RESULTS

A total of 103 donors were identified from records. Ninety three of these had detailed clinical records to complement their CT scans. Fifty of ninety-three donors were male, and the mean age was 45.9 ± 1.8 years. Mean MDRD eGFR was 88.73 ± 2.97 ml/min/1.73 m(2). 7.14 ± 3.07 % of the aorta in these donors was calcified with a mean AAC severity score of 0.98 ± 0.56. In kidney donors >50 years of age, there was significantly more AAC than in those <50: 2.47 ± 1.56 versus 0.31 ± 0.29, p < 0.001. There was no relationship between the presence or severity of aortic VC and donor GFR, systolic blood pressure, pulse pressure, calcium-phosphate product or smoking.

CONCLUSIONS

AAC prevalence, patterns and severity in this important donor population have not previously been described in the literature. There was relatively little VC in what would be regarded as a "healthy" donor population. VC was more common with age, but the other possible risk factors for the presence or severity of VC did not impact on overall AAC scores. VC did not influence vascular stiffness as represented by pulse pressure. Following the evolution of AAC over time in those who have donated a kidney, and lost some global renal function as a consequence, would be of considerable interest.

Custom-made rotating hinge total knee replacement in a patient with congenital tibial deficiency avoids the need for amputation

We report a unique case of a patient with type 2 congenital tibial deficiency and disabling knee osteoarthritis in whom a custom-made rotating hinge knee replacement was successfully performed, allowing continued mobilisation with a below-knee prosthesis, thereby avoiding the need for an above-knee amputation. Level of evidence Therapeutic study, Level IV.

Intercalary diaphyseal endoprosthetic reconstruction for malignant tibial bone tumours

The best method of reconstruction after resection of malignant tumours of the tibial diaphysis is unknown. In the absence of any long-term studies analysing the results of intercalary endoprosthetic replacement, we present a retrospective review of 18 patients who underwent limb salvage using a tibial diaphyseal endoprosthetic replacement following excision of a malignant bone tumour. There were ten men and eight women with a mean age of 42.5 years (16 to 76). Mean follow-up was 58.5 months (20 to 141) for all patients and 69.3 months (20 to 141) for the 12 patients still alive. Cumulative patient survival was 59% (95% confidence interval (CI) 32 to 84) at five years. Implant survival was 63% (95% CI 35 to 90) at ten years. Four patients required revision to a proximal tibial replacement at a mean follow-up of 29 months (10 to 54). Complications included metastases in five patients, aseptic loosening in four, peri-prosthetic fracture in two, infection in one and local recurrence in one. The mean Musculoskeletal Tumor Society score and the mean Toronto Extremity Salvage Score were 23 (17 to 28) and 74% (53 to 91), respectively.

Although rates of complication and revision were high, custom-made tibial diaphyseal replacement following resection of malignant bone tumours enables early return to function and provides an attractive alternative to other surgical options, without apparent compromise of patient survival.

Complications of intestinal stomas

BACKGROUND

Stomal complications are prevalent and associated with considerable morbidity. This study examined the incidence and potential risk factors for their development.

METHODS

The time of onset and presence of ten specific complications were recorded for patients with an intestinal stoma over 10 years at two urban hospitals. A database was established with 20 explanatory variables (such as common medical co-morbidities) derived from the stomatherapy and medical records. Univariable and multivariable analyses were performed to identify potential risk factors for the development of complications.

RESULTS

Some 1216 patients (mean age 64 years) with a minimum of 2 years' follow-up were included, of whom 544 (44·7 per cent) underwent surgery for malignancy and 647 (53·2 per cent) had a colostomy formed. There were 1219 complications in total; 807 major complications (excluding excoriation and slough) occurred in 564 patients (46·4 per cent), of which the commonest was parastomal hernia (171, 14·1 per cent). On multivariable analysis, musculoskeletal co-morbidity (odds ratio (OR) 1·79, 95 per cent confidence interval 1·05 to 3·07; P = 0·032), cancer (OR 1·48, 1·13 to 1·93; P = 0·004) and high American Association of Anesthesiologists score (OR = 3·80, 2·14 to 6·75; P < 0·001) were associated with an increased risk of complications. Preoperative siting was associated with a reduced risk (OR 0·59, 0·39 to 0·90; P = 0·014).

CONCLUSION

Intestinal stomal complications are common, occurring in almost half of patients. There are certain irremediable risk factors, allowing appropriate preoperative counselling.

Fistulization in a locally advanced case of squamous cell carcinoma of the prostate

Squamous cell carcinoma of the prostate gland is very rare, constituting 0.5%-1% of all prostatic malignancies. Though it has a similar clinical presentation to prostate cancer, the tumor is more aggressive, spreading to bone, liver and lung. The median survival time is approximately 14 months. Diagnosis is exclusively by histology. Therapeutic options may include radical surgery, radiotherapy, chemotherapy, hormonal therapy or a combination of these treatments. We present a case of locally advanced squamous cell carcinoma of the prostate and comment on its management and subsequent disease related complication.

Substance misuse in the older population

Substance misuse among the older population is largely overlooked and underreported. Many factors contribute to this, not least the fact that presentation may be atypical and hence easily missed by the medical practitioner. There may be many clues to its existence, provided the physician remains alert to these. Despite this it is quite comforting to know that once identified, the evidence to date suggests that older people may respond at least as well as younger people to treatment.

Gene expression in rat dermal papilla cells: analysis of 2529 ESTs

Dermal papilla (DEPA) cells are resident at the base of hair follicles and are fundamental to hair growth and development. Cultured DEPA cells, in contrast to normal fibroblast cells, are capable of inducing de novo hair follicle growth in vivo. By differential screening of a DEPA cDNA library, we have demonstrated that dermal papilla cells are different from fibroblasts at the molecular level. We further studied these cells by random sequencing of 5130 clones from the DEPA cDNA library. Fifty percent had a BLASTX E value < or =1 x 10(-25). Twenty-one percent had similarity to proteins involved in cell structure/motility with 4 of the top 10 most abundant clones encoding extracellular matrix proteins. Clones encoding growth factor molecules were also abundant. The remaining 50.7% of clones had low similarity scores, demonstrating many novel molecules. For example, we identified a new CTGF family member, the rat homologue of Elm1.

Nurses' perception and experiences of advocacy

This small qualitative research study, undertaken for a Bachelor (Honours) Course, was aimed at discovering nurses' perceptions and experiences of advocacy, through focused, in-depth interviews. Thematic analysis identified seven major themes: advocacy as a moral obligation, knowing the patient, triggers to becoming an advocate, considering the consequences, the difficulties of advocating, becoming an effective advocate and outcomes of advocacy. When further examined, these themes suggested that advocacy is a process rather than an event. The themes are supported from the data and the steps in the process are outlined and offered as a tentative model of nursing advocacy. This study increases understanding of advocacy from a nursing perspective and may help minimise the difficulties of enacting an advocacy role.

Respiratory assessment in critical care units

As healthcare delivery changes in critical care, nursing continues to extend its practice base. Nursing practice is expanding to incorporate skills once seen as the remit of the medical profession. Critical care nurses are equipping themselves with evidence-based knowledge and skills that can enhance the care they provide to their patients. Assessment of patients is a major role in nursing and, by expanding assessment techniques, nurses can ensure patients receive the care most appropriate to their needs. Nurses in critical care are well placed to perform a more detailed assessment which can help to focus nursing care. This article describes the step-by-step process of undertaking a full and comprehensive respiratory assessment in critical care settings. It identifies many of the problems that patients may have and the signs and symptoms that a nurse may not whilst undertaking the assessment and preparing to prescribe care.

Predictors of outcome in cauda equina syndrome

This retrospective review examined the cause, level of pathology, onset of symptoms, time taken to treatment, and outcome of 19 patients with cauda equina syndrome (CES). The minimum time to follow up was 22 months. Logistical regression analysis was used to determine how these factors influenced the eventual outcome. Out of 19 patients, 14 had satisfactory recovery at 2 years post-decompression; 5 patients were left with some residual dysfunction. The mean time to decompression in the group with a satisfactory outcome was 14 h (range 6-24 h) whilst that of the group with the poor outcome was 30 h (range 20-72 h). There was a clear correlation between delayed decompression and a poor outcome (P = 0.023). Saddle hypoaesthesia was evident in all patients. In addition complete perineal anaesthesia was evident in 7/19 patients, 5 of whom developed a poor outcome. Bladder dysfunction was observed in 19/19 patients, with 12/19 regarded as having significant impairment. Of the five patients identified as having a poor overall outcome, all five presented with a significant sphincter disturbance and 4/5 were left with residual sphincter dysfunction. There was a clear correlation between the presence of complete perineal anaesthesia and significant sphincter dysfunction as both univariate and multivariate predictors of a poor overall outcome. The association between a slower onset of CES and a more favourable outcome did not reach statistical significance (P = 0.052). No correlation could be found between initial motor function loss, bilateral sciatica, level or cause of injury as predictors of a poor outcome (P>0.05). CES can be diagnosed early by judicious physical examination, with particular attention to perineal sensation and a history of urinary dysfunction. The most important factors identified in this series as predictors of a favourable outcome in CES were early diagnosis and early decompression.

MIAH: automatic alignment of eukaryotic SSU rRNAs

SUMMARY

MIAH is a WWW server for the automatic alignment of new eukaryotic SSU rRNA sequences to an existing alignment of 1500 sequences.

AVAILABILITY

http://chah.ucc.ie/MIAH Contact :

Cardiac and circulatory assessment in intensive care units

As healthcare delivery changes in critical care, nursing continues to evolve and develop. Nursing skills are expanding to incorporate skills once seen as the remit of the medical profession. Nurses are now equipping themselves with the skills and knowledge that can enhance the care they provide to their patients. Assessment of patients is a major role in nursing and, by expanding assessment skills, nurses can ensure that patients receive the care most appropriate to their needs. Nurses in critical care settings are well placed to carry out a more detailed assessment, which can help to focus nursing care. This article describes the step-by-step process of undertaking a full and comprehensive cardiac and circulatory assessment in a clinical setting. It identifies many of the problems that patients may have and the signs that the nurse may note whilst undertaking the assessment.

Sequence analysis of DNA randomly amplified from the Saccharomyces cerevisiae genome

Despite its widespread use, the molecular basis of random amplification is poorly understood. Here the basis of random amplification has been investigated by cloning and sequencing the products of a random amplification of polymorphic DNA (RAPD) amplification from Saccharomyces cerevisiae DNA. The genomic origin of the amplified products was determined by sequence comparison with the S. cerevisiae Genome Database (SGD). This allowed analysis of the degree of identity between the random primer and the primer binding sites on the genome. There was no relationship between RAPD size, GC content and relative abundance. The degree of matching between the primer and the primer binding sites increased towards the 3; end of the primer and decreased towards the 5; end. The maximum number of mismatches observed between primer and primer binding sites was never more than one between positions 1-7 of the primer. Nucleotide compositional biases were also observed upstream and downstream of the primer binding site with a marked preference for AT richness upstream of the primer binding sites and for a GC preference directly following the 3; end of the primer. These findings have important ramifications for primer design for multiplex, low stringency and degenerate polymerase chain reaction (PCR).

Knowledge and attitudes to prescribed drugs in young and elderly patients

Increasing patient knowledge of drug therapy is said to improve compliance and may reduce adverse drug reactions. We assessed patient knowledge of prescribed drugs in fifty patients attending a hypertension clinic [outpatients] and in elderly patients on admission to (n = 129) and on discharge from (n = 100) an acute geriatric assessment unit. We found that 88% of outpatients, 40% of elderly admissions, and 41% of elderly discharges knew the indications for their therapy; only 40% of outpatients, 8% of elderly admissions and 12% of elderly discharges could name their medications. Patients said that their information came principally from the prescribing doctor. In a further study we assessed doctor, nurse, young and elderly patients' ability to discriminate between commonly prescribed white tablets. Errors were made by the doctors on 25% occasions, nurses on 40% occasions and patients on 61% occasions. Young patients made errors 67% of the time and elderly patients 55% of the time. These studies indicate that both inpatients and outpatients, both young and elderly have poor knowledge of their medications. In addition, many commonly prescribed drugs are not easily distinguishable by patient, prescriber or drug administrator. We conclude that there is a need to improve knowledge both in patients and in prescribers. We suggest that prescribers should consider the colour and shape of medications prescribed concurrently as many "little white tablets" are difficult to tell apart.

Low blood pressure in Down's syndrome, A link with Alzheimer's disease?

Low blood pressure is reported in Down's syndrome (DS). To assess this and determine whether low pressure results from the disease or from long-term residence in hospital, we measured blood pressure with a random-zero sphygmomanometer in three groups of patients: 52 DS inpatients, 62 DS outpatients, and 60 outpatients with other forms of mental handicap. Relative to normal reference populations, blood pressure was low in both DS inpatients (systolic, score -33 mm Hg, P < .0001) and DS outpatients (-25 mm Hg, P < .0001). It was normal in non-DS outpatients (-4.0 mm Hg, P = .3). Blood pressure rose normally with age in the non-DS group but not in the DS group. We conclude that blood pressure is low in DS and that this is a feature of the disease rather than of the protected environment in which patients live. A mechanism related to trisomy 21 is likely, and there may be a link with Alzheimer's disease (AD) because blood pressure is also low in Alzheimer's and a high proportion of Ds patients develop this disease. If, as is likely, blood pressure is lowered in Alzheimer's by the neuropathy, the same neuropathy developing early in DS may also reduce blood pressure.

Occupational stress in nursing

This article reports the results of a study of occupational stress undertaken with a large sample of Northern Ireland nurses, including qualified staff (both community and hospital based) up to and including sister/charge nurses. This study formed part of a wider interprofessional study of nurses, social workers and teachers. Publications for the latter two professions, along with interprofessional comparisons, are in preparation and this present article focuses on the nursing cohort. The design and methods are described and demographic characteristics of the nursing sample are provided with their views about nursing. Stressors are identified in both professional and private lives. The effects of stress as manifested through the General Health Questionnaire and the Maslach Burnout Inventory are examined and nurses' views on various stress-coping strategies are discussed.

Myocyte hypertrophy in neonatal rat heart cultures and its regulation by serum and by catecholamines

The role of hormones and other humoral factors in the regulation of myocardial hypertrophy has been difficult to evaluate. We asked whether myocardial cell hypertrophy could be demonstrated in cultures from the day-old rat ventricle and evaluated the effect of serum concentration and catecholamines on the growth process. Two single-cell preparations were used: serum-supplemented, bromodeoxyuridine-treated cultures and serum-free cultures with transferrin and insulin. Both preparations were characterized by myocardial cell predominance (about 75--80% of total cells) and constant cell numbers. Myocardial cell size was documented by photomicroscopy and quantified by volume (microscopic diameter of suspended cells), surface area (planimetry of attached cells), and total cell protein concentration (Lowry method and cell counts). Growth was also evaluated in pure nonmyocardial cell cultures. In cultures with 5% (vol/vol) serum, myocardial cell size increased 2- to 3-fold over 11 days in culture. Final volume, surface area, and protein concentration were about 3000 micrometer3/cell, 5000 micrometer2/cell, and 1500 pg/cell, respectively. Serum had a dose-related effect on myocardial cell hypertrophy; myocardial cell size increased about 4-fold when serum concentration was increased from 0% to 5% or 10%. Cells maintained in serum-free medium with transferrin and insulin (each 10 microgram/ml) did not hypertrophy, but did remain responsive to the growth-promoting activity of serum. Chronic exposure to isoproterenol or norepinephrine (1 microM) significantly stimulated myocardial cell hypertrophy. This stimulation was dose-related, was not blocked by equimolar propranolol, was not associated with a sustained chronotropic effect, and was more pronounced in the serum-free preparation. In pure cultures of nonproliferating (bromodeoxyuridine-treated) nonmyocardial cells, cell size also increased with time in culture, but variation in serum concentration and addition of norepinephrine had no significant effect on cell size. Myocardial cell hypertrophy occurs in culture and is regulated by variations in the culture medium, including serum, with its contained hormones and growth factors, and catecholamines. The culture preparation can be used to explore the regulation of myocardial cell hypertrophy by nonhemodynamic factors.

Ultrasonic investigation of the brain in neonates

A brief history of echoencephalography is given. Recent advances in ultrasonic technology have resulted in renewed interest in the subject. The neonatal brain can now be reliably visualised with systems which are widely available. Ultrasound examination is a relatively simple, safe procedure which does not cause distress to the patient. This makes it particularly suited to investigation of neonates. The examination technique used in our department is described. Other techniques and studies comparing ultrasound with other modalities are briefly reviewed.

Response of Cloudman S91 melanoma cells to melanocytestimulating hormone: enhancement by cytochalasin B

Cloudmann S 91 mouse melanoma cells treated for 5 days with melanocyte-stimulating hormone (MSH), cytochalasin B (CB), or both, exhibited changes in cell volume, population, nucleation, and pigment production. Cells treated with CB or CB in combination with MSH were eight to nine times larger, rounder, multinucleated, and heavily pigmented. CB alone increased melanin and DNA per nucleus threefold. CB in combination with MSH increased melanin per nucleus 30-fold. Data on DNA per nucleus suggest that CB-treated cells remained in the G phase longer than did control cells. MSH alone caused a reduction in cell population and a fourfold increase in melanin per nucleus.