Tuning Proton Insertion Chemistry for Sustainable Aqueous Zinc-Ion Batteries

Rechargeable aqueous zinc-ion batteries (ZIBs) have emerged as an alternative to lithium-ion batteries due to their affordability and high level of safety. However, their commercialization is hindered by the low mass loading and irreversible structural changes of the cathode materials during cycling. Here, a disordered phase of a manganese nickel cobalt dioxide cathode material derived from wastewater via a coprecipitation process is reported. When used as the cathode for aqueous ZIBs , the developed electrode delivers 98% capacity retention at a current density of 0.1 A g-1 and 72% capacity retention at 1 A g-1 while maintaining high mass loading (15 mg cm-2). The high performance is attributed to the structural stability of the Co and Ni codoped phase; the dopants effectively suppress Jahn-Teller distortion of the manganese dioxide during cycling, as revealed by operando X-ray absorption spectroscopy. Also, it is found that the Co and Ni co-doped phase effectively inhibits the dissolution of Mn2+, resulting in enhanced durability without capacity decay at first 20 cycles. Further, it is found that the performance of the electrode is sensitive to the ratio of Ni to Co, providing important insight into rational design of more efficient cathode materials for low-cost, sustainable, rechargeable aqueous ZIBs.

A Synergistic Three-Phase, Triple-Conducting Air Electrode for Reversible Proton-Conducting Solid Oxide Cells

Reversible proton-conducting solid oxide cells (R-PSOCs) have the potential to be the most efficient and cost-effective electrochemical device for energy storage and conversion. A breakthrough in air electrode material development is vital to minimizing the energy loss and degradation of R-PSOCs. Here we report a class of triple-conducting air electrode materials by judiciously doping transition- and rare-earth metal ions into a proton-conducting electrolyte material, which demonstrate outstanding activity and durability for R-PSOC applications. The optimized composition Ba0.9Pr0.1Hf0.1Y0.1Co0.8O3-δ (BPHYC) consists of three phases, which have a synergistic effect on enhancing the performance, as revealed from electrochemical analysis and theoretical calculations. When applied to R-PSOCs operated at 600 °C, a peak power density of 1.37 W cm-2 is demonstrated in the fuel cell mode, and a current density of 2.40 A cm-2 is achieved at a cell voltage of 1.3 V in the water electrolysis mode under stable operation for hundreds of hours.

Durable and High-Performance Thin-Film BHYb-Coated BZCYYb Bilayer Electrolytes for Proton-Conducting Reversible Solid Oxide Cells

Proton-conducting reversible solid oxide cells are a promising technology for efficient conversion between electricity and chemical fuels, making them well-suited for the deployment of renewable energies and load leveling. However, state-of-the-art proton conductors are limited by an inherent trade-off between conductivity and stability. The bilayer electrolyte design bypasses this limitation by combining a highly conductive electrolyte backbone (e.g., BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3-δ (BZCYYb1711)) with a highly stable protection layer (e.g., BaHf_0.8Yb_0.2O_3-δ (BHYb82)). Here, a BHYb82-BZCYYb1711 bilayer electrolyte is developed, which dramatically enhances the chemical stability while maintaining high electrochemical performance. The dense and epitaxial BHYb82 protection layer effectively protects the BZCYYb1711 from degradation in contaminating atmospheres such as high concentrations of steam and CO₂. When exposed to CO₂ (3% H₂O), the bilayer cell degrades at a rate of 0.4 to 1.1%/1000 h, which is much lower than the unmodified cells at 5.1 to 7.0%. The optimized BHYb82 thin-film coating adds negligible resistance to the BZCYYb1711 electrolyte while providing a greatly enhanced chemical stability. Bilayer-based single cells demonstrated state-of-the-art electrochemical performance, with a high peak power density of 1.22 W cm^-2 in the fuel cell mode and -1.86 A cm^-2 at 1.3 V in the electrolysis mode at 600 °C, while demonstrating excellent long-term stability.

Patella Denervation With Circumferential Electrocautery in Primary Knee Arthroplasty: A Randomized Controlled Trial

BACKGROUND

The aim of this study was to investigate the clinical effectiveness of patella rim electrocautery "denervation" versus no denervation in patients undergoing total knee arthroplasty (TKA).

METHODS

We conducted a single-center, double-blind randomized controlled trial. Patients aged 40 years or older, due to undergo a TKA who did not have patella resurfacing (usual care) were randomized with or without circumferential patella electrocautery. This was undertaken according to a randomly generated sequence of treatment allocation that was placed into numbered, sealed opaque envelopes. Participants were blinded to treatment allocation. There was no crossover. The primary outcome was Oxford Knee Score at 1 year postoperatively. Secondary outcomes were Bartlett Patella Score, Western Ontario and McMaster Universities Arthritis Index (WOMAC), and 12-Item Short Form Survey. Linear regression analyses were performed with adjustments by age, sex, and baseline (preoperative) scores. There were 142 participants recruited, of which 49 (35%) were allocated to the denervation intervention. Recruitment was stopped early when interim statistical analyses confirmed adequate numbers in both groups despite an imbalance in early treatment allocation rates due to the randomization method. The mean patient age was 71 years (range, 50 to 85) and 51% (n = 74) were women.

RESULTS

No difference in Oxford Knee Score was detected at 1 year (mean difference [MD] 1.87; 95% confidence interval [CI] -1.28 to 5.03). No difference was detected in Bartlett Patella Score (MD 0.490; 95% CI -1.61 to 2.59) or 12-Item Short Form Survey (MD 0.196; 95% CI -2.54 to 2.93). A statistically significant difference in WOMAC was detected, but at a level less than the minimal clinically important difference for WOMAC (MD 4.79; 95% CI 1.05 to 8.52).

CONCLUSION

No clinically relevant benefit was detected from patella rim electrocautery in patients undergoing TKA who did not have patella resurfacing (including no benefit in terms of anterior knee pain). This treatment is therefore not recommended for clinical practice.

LEVEL OF EVIDENCE

Level 1.

A New Class of Proton Conductors with Dramatically Enhanced Stability and High Conductivity for Reversible Solid Oxide Cells

Reversible solid oxide cells based on proton conductors (P-ReSOCs) have potential to be the most efficient and low-cost option for large-scale energy storage and power generation, holding promise as an enabler for the implementation of intermittent renewable energy technologies and the widespread utilization of hydrogen. Here, the rational design of a new class of hexavalent Mo/W-doped proton-conducting electrolytes with excellent durability while maintaining high conductivity is reported. Specifically, BaMo(W)_0.03 Ce_0.71 Yb_0.26 O_3-δ exhibits dramatically enhanced chemical stability against high concentrations of steam and carbon dioxide than the state-of-the-art electrolyte materials while retaining similar ionic conductivity. In addition, P-ReSOCs based on BaW_0.03 Ce_0.71 Yb_0.26 O_3-δ demonstrate high peak power densities of 1.54, 1.03, 0.72, and 0.48 W cm^-2 at 650, 600, 550, and 500 °C, respectively, in the fuel cell mode. During steam electrolysis, a high current density of 2.28 A cm^-2 is achieved at a cell voltage of 1.3 V at 600 °C, and the electrolysis cell can operate stably with no noticeable degradation when exposed to high humidity of 30% H₂ O at -0.5 A cm^-2 and 600 °C for over 300 h. Overall, this work demonstrates the promise of donor doping for obtaining proton conductors with both high conductivity and chemical stability for P-ReSOCs.

Elective hip arthroplasty rates and related complications in people with diabetes mellitus

BACKGROUND AND AIMS

Diabetes mellitus (DM), poor glycaemic control and raised body mass index (BMI) have been associated with postoperative complications in arthroplasty, although the relative importance of these factors is unclear. We describe the prevalence of DM in elective hip arthroplasty in a UK centre, and evaluate the impact of these factors.

METHODS

We analysed retrospective data for DM patients undergoing arthroplasty over a 6-year period and compared with non-diabetic matched controls (1 DM patient: 5 controls). DM was present in 5.7% of hip arthroplasty patients (82/1443).

RESULTS

Postoperative complications occurred in 12.2% of DM patients versus 12.9% of controls (p = 1.000); surgical complications were present in 6.1% of those with DM and 2.4% of controls (p = 0.087), while medical complications occurred in 8.5% of DM patients versus 10.7% of controls (p = 0.692). Complications developed in 23.1% of DM patients with poor glycaemic control (HbA1c > 53 mmol/mol) versus 9.8% with good control (p = 0.169). In DM patients and controls combined, complications occurred in 16.3% of obese patients versus 10.0% of non-obese patients (p = 0.043). In the DM cohort, 13.7% of overweight patients had complications versus 0% with a normal or low BMI (p = 0.587).

CONCLUSIONS

DM rates were lower than expected, and glycaemic control was good. Overall complication rates were unrelated to the presence of DM or to glycaemic control, although surgical complications were observed more frequently in those with DM and poor glycaemic control was uncommon within our cohort. Complications were more frequent in those with a higher BMI. Whether some patients with DM but without an increased risk of complications are currently being excluded from surgery requires exploration.

Genetic control of rhizosheath formation in pearl millet

The rhizosheath, the layer of soil that adheres strongly to roots, influences water and nutrients acquisition. Pearl millet is a cereal crop that plays a major role for food security in arid regions of sub-Saharan Africa and India. We previously showed that root-adhering soil mass is a heritable trait in pearl millet and that it correlates with changes in rhizosphere microbiota structure and functions. Here, we studied the correlation between root-adhering soil mass and root hair development, root architecture, and symbiosis with arbuscular mycorrhizal fungi and we analysed the genetic control of this trait using genome wide association (GWAS) combined with bulk segregant analysis and gene expression studies. Root-adhering soil mass was weakly correlated only to root hairs traits in pearl millet. Twelve QTLs for rhizosheath formation were identified by GWAS. Bulk segregant analysis on a biparental population validated five of these QTLs. Combining genetics with a comparison of global gene expression in the root tip of contrasted inbred lines revealed candidate genes that might control rhizosheath formation in pearl millet. Our study indicates that rhizosheath formation is under complex genetic control in pearl millet and suggests that it is mainly regulated by root exudation.

Cement-in-cement femoral component revision : a comparison of two different taper-slip designs with medium-term follow up

AIMS

Cement-in-cement revision of the femoral component represents a widely practised technique for a variety of indications in revision total hip arthroplasty. In this study, we compare the clinical and radiological outcomes of two polished tapered femoral components.

METHODS

From our prospectively collated database, we identified all patients undergoing cement-in-cement revision from January 2005 to January 2013 who had a minimum of two years' follow-up. All cases were performed by the senior author using either an Exeter short revision stem or the C-Stem AMT high offset No. 1 prosthesis. Patients were followed-up annually with clinical and radiological assessment.

RESULTS

A total of 97 patients matched the inclusion criteria (50 Exeter and 47 C-Stem AMT components). There were no significant differences between the patient demographic data in either group. Mean follow-up was 9.7 years. A significant improvement in Oxford Hip Score (OHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and 12-item Short-Form Survey (SF-12) scores was observed in both cohorts. Leg lengths were significantly shorter in the Exeter group, with a mean of -4 mm in this cohort compared with 0 mm in the C-Stem AMT group. One patient in the Exeter group had early evidence of radiological loosening. In total, 16 patients (15%) underwent further revision of the femoral component (seven in the C-Stem AMT group and nine in the Exeter group). No femoral components were revised for aseptic loosening. There were two cases of femoral component fracture in the Exeter group.

CONCLUSION

Our series shows promising mid-term outcomes for the cement-in-cement revision technique using either the Exeter or C-Stem AMT components. These results demonstrate that cement-in-cement revision using a double or triple taper-slip design is a safe and reliable technique when used for the correct indications. Cite this article: Bone Joint J 2021;103-B(7):1215-1221.

High-Performance, Thermal Cycling Stable, Coking-Tolerant Solid Oxide Fuel Cells with Nanostructured Electrodes

Solid oxide fuel cells (SOFCs) are a promising solution to a sustainable energy future. However, cell performance and stability remain a challenge. Durable, nanostructured electrodes fabricated via a simple, cost-effective method are an effective way to address these problems. In this work, both the nanostructured PrBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+δ (PBSCF) cathode and Ni-Ce_0.8Sm_0.2O_1.9 (SDC) anode are fabricated on a porous yttria-stabilized zirconia (YSZ) backbone via solution infiltration. Symmetrical cells with a configuration of PBSCF|YSZ|PBSCF show a low interfacial polarization resistance of 0.03 Ω cm² with minimal degradation at 700 °C for 600 h. Ni-SDC|YSZ|PBSCF single cells exhibit a peak power density of 0.62 W cm^-2 at 650 °C operated on H₂ with good thermal cycling stability for 110 h. Single cells also show excellent coking tolerance with stable operation on CH₄ for over 120 h. This work offers a promising pathway toward the development of high-performance and durable SOFCs to be powered by natural gas.

Lower urinary tract dysfunction in children after intravesical ureteric reimplantation surgery under one year of age

OBJECTIVE

To report the results of a study conducted on voiding function in children who have undergone intravesical trans-trigonal Cohen ureteric reimplantation surgery before the age of one year.

SUBJECTS

Twenty-eight children (18 males, 10 females) had surgery at a mean age of 4.9 months (range 8-352 days).

METHODS

Bladder function was assessed at a mean age of 7.3 years using questionnaires, the dysfunctional voiding scoring system, PinQ quality of life tool, uroflowmetry and post-void residuals.

RESULTS

Of the total children, 72% had normal lower urinary tract (LUT) function. Eight children (28%) had evidence of LUT dysfunction, two had urge incontinence, two had giggle incontinence, two had voiding postponement, one had dysfunctional elimination syndrome and one had evidence of dysfunctional voiding. Five of the eight children were managed with continence physiotherapy (urotherapy) and one required ongoing anticholinergic therapy.

CONCLUSION

When compared to the published rates of LUT dysfunction in the general paediatric community, no evidence was found to suggest an increased incidence of bladder dysfunction in children undergoing intravesical Cohen ureteric reimplantation surgery under one year of age.

Safety and feasibility of autologous bone marrow cellular therapy in relapsing-progressive multiple sclerosis

In this phase I study, we assessed the safety and feasibility of intravenous, autologous bone marrow (BM) cell therapy, without immunosuppressive preconditioning, in six patients with clinically definite, relapsing-progressive multiple sclerosis (MS). Assessment of efficacy was a secondary objective and employed clinical disability rating scales, multimodal evoked potential (MMEP) recordings, and magnetic resonance imaging (MRI) scans. Cells were harvested, filtered and infused intravenously in a day-case procedure that was well tolerated by patients and was not associated with any serious adverse events (AEs). Over a period of 12 months after the therapy, clinical disability scores showed either no change (Extended Disability Status Score, EDSS) or improvement (MS impact scale-29, MSIS-29), and MMEPs showed neurophysiological improvement. MRI scans did not show any significant changes over a post-therapy period of 3 months. The lack of serious adverse effects and the suggestion of a beneficial effect in this small sample of patients with progressive disease justify conducting a larger phase II/III study to make a fuller assessment of the efficacy of mobilization of autologous BM in patients with MS.

Investigation of the cerebral response to flicker stimulation in patients with headache

Migraine affects 10% of the population, yet there is no proven diagnostic test. To date the most promising neurophysiological diagnostic technique has been the analysis of cerebral responses to photic stimulation or flicker (the "H" response). This test has proved to be sensitive in patients with "classic" migraine, but has not been re-evaluated since the introduction of the 1988 International Headache Society (IHS) classification system. In 33 migraineurs, we found that the "H" response was sensitive (86.4%) and specific (97.5%) in those with migraine defined according to IHS Committee as type 1.2.1 (typical aura) and type 1.1 (without aura), but not in basilar migraine (1.2.4).

The rough deal protein is a new kinetochore component required for accurate chromosome segregation in Drosophila

Mutations in the rough deal (rod) gene of Drosophila greatly increase the missegregation of sister chromatids during mitosis, suggesting a role for this gene product in spindle or kinetochore function. The activity provided by rod also appears to be necessary for the recruitment of two known kinetochore components, Zw10 and cytoplasmic dynein. In this paper we describe the cloning of rough deal and an initial cytological characterization of its product. The Rod protein shares no identifiable structural motif with other known proteins, although apparent homologs exist in the genomes of nematode and man. By immunocytochemistry we show that Rod displays a dynamic intracellular staining pattern, localizing first to kinetochores in prometaphase, but moving to kinetochore microtubules at metaphase. Early in anaphase the protein is once again restricted to the kinetochores, where it persists until the end of telophase. This behavior is in all respects similar to that described for Zw10, and suggests that the proteins function together.

Cancer treatment in rural areas

The inability to deliver cancer prevention and treatment to the rural population poses a significant barrier in the national effort to reduce cancer mortality. Since 25 percent of the U.S. population lives in rural areas and few rural areas are readily accessible to cancer centers or Community Clinical Oncology Programs (CCOPs), the prospects for accomplishing the National Cancer Institute (NCI) Goals for the Year 2000 are limited unless substantive changes occur in rural cancer care delivery. This article reviews the problem of cancer risk and care in rural areas and describes one effort to deliver state-of-the-art cancer treatment to rural patients in Virginia. It describes the needs and barriers to access in rural Virginia, the structural elements of the Rural Cancer Outreach Program, and the health policy issues that result when subspecialty care is exported to disadvantaged areas.

Percutaneous abdominal biopsy: cost-identification analysis

PURPOSE

To determine the difference in cost to providers of percutaneous abdominal biopsy as the first strategy versus surgical biopsy.

MATERIALS AND METHODS

Cost of tissue diagnosis determination with percutaneous biopsy as the first strategy in 439 patients with an abdominal mass was estimated. Costs included direct hospital costs and professional costs of initial and repeat biopsy, follow-up imaging and clinic visits, surgical biopsy (when needed), and treatment of complications. The sum of these costs was compared with the estimated cost had the same patients undergone surgical biopsy instead, with no complications or need for follow-up or repeat biopsy.

RESULTS

The total estimated cost of percutaneous biopsy as the first strategy ($543,245) was less than the cost had surgical biopsy been used alone ($1,919,867). The average per patient direct hospital cost of percutaneous biopsy ($800) was lower than that of surgical biopsy ($3,419). The average per patient professional cost of percutaneous biopsy ($438) was also lower than that of surgical biopsy ($955). Savings averaged $3,136 per patient, or $1,376,622 for the study period.

CONCLUSION

Substantial health care cost savings may result by using a diagnostic algorithm in which percutaneous biopsy is the first strategy for establishment of a diagnosis in patients suspected of having abdominal malignancy.

CARPAL TUNNEL SYNDROME IN THE MUCOPOLYSACCHARIDOSES AND MUCOLIPIDOSES

Children with a mucopolysaccharidosis or mucolipidosis suffer progressive disability of the hands, particularly in relation to dysfunction of the median nerve. This is an increasing problem because bone-marrow transplantation has dramatically improved survival without apparently changing the musculoskeletal manifestations. We have reviewed 48 children with these syndromes who required carpal tunnel decompression, recording symptoms, signs, radiological, electrophysiological and operative findings, histology and upper-limb function. In these children the carpal tunnel syndrome differs from that seen in adults. Symptoms are rare but signs such as decreased sweating, pulp atrophy, thenar wasting and manual clumsiness are much more common. At operation, the flexor retinaculum was thickened and a mass of white tenosynovium engulfed the flexor tendons. Most patients had some definite nerve constriction with a thickened epineurium.

Functional improvement was seen after early decompression, with some benefit from simultaneous tendon release. Regular physiotherapy helped to maintain increased hand movement.

We describe our assessment protocol, the physiotherapy and operative regime and the standard functional review which helps to maximise function in the hands and upper limbs of these children.

Carpal tunnel syndrome in the mucopolysaccharidoses and mucolipidoses

Children with a mucopolysaccharidosis or mucolipidosis suffer progressive disability of the hands, particularly in relation to dysfunction of the median nerve. This is an increasing problem because bone-marrow transplantation has dramatically improved survival without apparently changing the musculoskeletal manifestations. We have reviewed 48 children with these syndromes who required carpal tunnel decompression, recording symptoms, signs, radiological, electrophysiological and operative findings, histology and upper-limb function. In these children the carpal tunnel syndrome differs from that seen in adults. Symptoms are rare but signs such as decreased sweating, pulp atrophy, thenar wasting and manual clumsiness are much more common. At operation, the flexor retinaculum was thickened and a mass of white tenosynovium engulfed the flexor tendons. Most patients had some definite nerve constriction with a thickened epineurium. Functional improvement was seen after early decompression, with some benefit from simultaneous tendon release. Regular physiotherapy helped to maintain increased hand movement. We describe our assessment protocol, the physiotherapy and operative regime and the standard functional review which helps to maximise function in the hands and upper limbs of these children.

Effect of chronic resistive loading on ventilatory control in a rat model

Acute resistive loading of the airway has been shown to activate the endogenous opioid system, with subsequent depression of ventilation. The present investigation was designed to assess the effect of chronic airway loading on ventilation and CO2 sensitivity, and to determine whether the endogenous opioid system contributes to long-term modulation of ventilatory control in this setting. A flow-resistive ventilatory load was imposed in 2-mo-old rats by surgical implantation of a circumferential tracheal band that approximately tripled tracheal resistance. Respiration and CO2 sensitivity were serially and noninvasively assessed by barometric plethysmography over a period of 21 wk. Ventilatory output was assessed as minute inspiratory effort, which was defined as the product of plethysmograph signal amplitude, inspiratory time, and respiratory rate (RR). CO2 sensitivity was calculated as the percent change in minute inspiratory effort from room air to CO2 exposure. The effect of naloxone administration on these parameters was also determine. Arterial blood gases demonstrated hypercapnia with maintenance of normoxia in loaded rats; these findings persisted for the duration of the study. Two days after surgery, rats with tracheal obstruction demonstrated a lower RR than controls during room air breathing and during CO2 stimulation. CO2 sensitivity was significantly depressed in obstructed animals at this time. Escape from suppression of RR and CO2 sensitivity was evident by 14 to 21 d after obstruction; however, suppression of these parameters reappeared and was maintained from 56 to 147 d after obstruction. Naloxone augmented minute inspiratory effort during CO2 stimulation at 2 d after obstruction but not thereafter; naloxone had no effect in control rats. These data indicate that chronic airway loading suppresses RR and CO2 sensitivity in a triphasic manner. The early suppression is partially reversible by naloxone; late-appearing suppression is unaffected by naloxone and is presumably mediated by mechanisms that do not involve endogenous opioids.

Metastasis of a renal carcinoma to a cerebellar haemangioblastoma in a case of von Hippel-Lindau disease

A patient with Von Hippel-Lindau disease had a long-standing cerebellar cyst which recurred for the fifth time. At operation there was evidence of a renal carcinoma metastasis in the wall of the cyst which was probably a haemangioblastoma.

Outcome following surgical evacuation of traumatic intracranial haematomas in the elderly

In order to determine the factors influencing outcome following craniotomy for trauma in patients over the age of 65 and to establish criteria for surgical intervention, the authors carried out a retrospective analysis of the hospital and general practice records of all head injury patients over the age of 65 who underwent a craniotomy for evacuation of a post-traumatic haematoma within 7 days of injury at Frenchay Hospital during a 10-year period (1980-89). Outcome was measured using the Glasgow Outcome Scale and patients were allotted to a good outcome group (good recovery or moderate disability but independent) or a poor outcome group (severe disability, vegetative state of death). There were 35 men and 31 women with a mean age of 72.5 years (range 65-85 years). The mortality rate was 61% and 9% of patients survived in a severely disabled or vegetative state. All 20 (30%) patients with a good outcome had a Glasgow Coma Score (GCS) of 5 or more immediately before surgery. All 18 (27%) patients with a GCS of 4 or less and all 22 (33%) patients with unilateral or bilateral pupillary dilatation had a poor outcome. Outcome was significantly worse in the older patients (75-85 years) compared with the younger patients (65-74 years) and in those patients requiring craniotomy within 24 hours of injury, but the mechanism of injury (fall or road traffic accident), the presence or absence of skull fractures and limb fractures and the pre-operative CT scan appearances did not influence outcome. This study confirms the high probability of poor outcome following surgical evacuation of traumatic intracranial haematomas for elderly head-injured patients with pupillary dilatation or extensor motor responses. Craniotomy under these circumstances is not justified.

Separation of beta-cells from dispersed porcine pancreas by selective lectin binding

Variation in cell-surface sugar residues which exist between different pancreatic cells has been exploited in an attempt to isolate beta-cells from dispersed porcine pancreas utilizing selective lectin binding. The binding characteristics of a range of lectins were compared to determine their ability to differentiate between endocrine and non-endocrine cells in the porcine pancreas. Histological analysis showed that peroxidase labelled Arachis hypogaea bound selectively to islet cells in Carnoy-fixed sections of pancreas. In five experiments, porcine pancreas was dispersed into single cells by collagenase digestion, incubated with fluorescein isothiocyanate-labelled Arachis hypogaea and analysed using a Fluorescence Activated Cell Sorter. Fluorescein isothiocyanate-labelled Arachis hypogaea bound to a population of cells comprising 6% +/- 4.2% (mean +/- s.d.) of the total. Cells from representative samples were sorted into populations, based on fluorescence. Immunohistochemical analysis of the fluorescent populations showed that 93% +/- 2% of these cells contained insulin: none of the cells stained positive for glucagon or somatostatin. These preliminary studies show that it is possible to separate porcine beta-cells from a dispersed cell preparation using a fluorescent labelled lectin.

Reduced tumour growth of the human colonic cancer cell lines COLO-320 and HT-29 in vivo by dietary n-3 lipids

Seventy-five nude mice received subcutaneous inoculation with 1 X 10(7) cells of the human colonic cancer cell lines COLO-320 or HT-29. Tumour growth was assessed over 4 weeks in animals given one of three iso-caloric diets; standard diet, high saturated fat (20% coconut) diet and high n-3 fat (20% Maxepa fish oil) diet. The n-3 diet produced significant tumour growth reduction compared to the other diets for COLO-320 at 3 to 4 weeks (P less than 0.05 at least) and similarly for HT-29 at 4 weeks (P less than 0.05). Significant incorporation of n-3 fatty acids occurred in red cell membranes, adipose tissue and both neutral lipid and phospholipid fractions of tumour lipids in animals fed Maxepa (P less than 0.01 at least). This was accompanied by reduction of linoleic acid and arachidonic acid in these tissues (P less than 0.01 at least) but was most marked in the metabolically labile phospholipid fraction. There was high mitotic activity in the tumours from all the groups but there was no difference according to diet.

Patterns of psychiatric morbidity in a genito-urinary clinic. A validation of the Hospital Anxiety Depression scale (HAD)

The prevalence of psychiatric disorder (by DSM-III criteria) in a population attending a genito-urinary clinic was found to be 31%. The performance of the Hospital Anxiety Depression (HAD) scale as a screening questionnaire for psychiatric disorder was assessed. Case definition by a score of 8 or more on either of the anxiety or depressive subscales produced optimal results, giving sensitivities of 82% and 70%, and specificities of 94% and 68%, for depressive and anxiety disorders respectively.

Arthroscopic subacromial decompression: results according to the degree of rotator cuff tear

We evaluated the results of arthroscopic subacromial decompression according to the degree of rotator cuff tear in 71 patients, available for follow-up for at least 1 year (average 19 months). Of the patients with stage II disease, 82% were satisfied regardless of whether they had no rotator cuff tear (nine of 11) or had a partial tear (28 of 34) of the rotator cuff. Of patients with stage III disease (complete rotator cuff tear), 88% (23 of 26) were satisfied. An acceptable objective UCLA shoulder rating greater than or equal to 28 points was seen in 82% (nine of 11) of the patients without a rotator cuff tear, 76% (26 of 34) with a partial tear, and 77% (20 of 26) with a complete tear. All four of the patients with complete tears less than 1 cm obtained excellent results. Three of the six failures were in patients with complete tears who had a narrowed acromial-humeral distance of less than 7 mm. The average UCLA pain score showed significant improvement from 2.8 (constant pain) to 8.6 (occasional pain) at 1-2 years postoperatively. The function, strength, and active forward flexion scores also increased at 1-2 years from their preoperative values. The overall patient satisfaction rate of 85% and the objective success rate of 77% are within the range of that seen with open rotator cuff repair.

[Determination of the novocaine salt of benzylpenicillin]

A simple procedure for acidometric titration of procaine benzylpenicillin after its chloroform extraction from alkaline solutions is described. Sodium benzylpenicillin does not prevent the titration.