The compounding effects of income loss and change in living arrangement on emerging adult women's mental health during COVID's onset

Research suggests that young adult women were among those more susceptible to mental health declines in the initial months of COVID-19. Unfortunately, longitudinal data examining mental health before and after the pandemic's onset are extremely limited. In a sample of 240 women ages 18-29 who were surveyed online first in November-December 2019 and then again between May and July 2020, this study aimed to examine how major life changes associated with the pandemic (i.e. loss of income, loss of employment, change in relationship status, and change in living arrangement) impacted mental health (i.e. depression, anxiety, stress). Multivariate regression analyses were conducted on three models predicting stress, anxiety, and depression from the four life changes, controlling for the effects of mental health before the COVID-19 pandemic. Results showed that a change in living arrangement was uniformly associated with increased mental health problems among women who also experienced a decrease in income. Likewise, loss of income was uniformly related to increased mental health problems among women who also experienced a change in living arrangement. In contrast, job loss was associated with a decrease in stress, and changes in relationship status were not associated with mental health outcomes. These findings highlight the potential for COVID-19 to produce co-occurring and synergistic stressors. Meanwhile, the impact of job loss on mental health may have been attenuated by enhanced unemployment benefits. Mental health interventions that aim to support young women as the pandemic abates should be tailored to address the impact of multiple psychosocial stressors.

Measurement of Ghrelin as a Marker of Appetite Dysregulation in Cats with and without Chronic Kidney Disease

Appetite abnormalities and weight loss are important comorbidities in the treatment of chronic kidney disease (CKD) in cats. Ghrelin, a key hormone involved in the regulation of appetite and metabolism, is a potential marker of appetite dysregulation in cats with CKD. The aim of this study was to compare the plasma concentrations of acylated, desacyl, and total ghrelin in normal cats and cats with CKD. Storage methodology was investigated prior to evaluating ghrelin concentrations in normal and CKD cats to facilitate clinical sample collection. Twelve normal cats and twelve cats with CKD were enrolled. Plasma acylated and total ghrelin concentrations were measured using radioimmunoassay. Desacyl ghrelin was calculated (total ghrelin minus acylated ghrelin). Cats with CKD had significantly increased total ghrelin and calculated desacyl ghrelin concentrations in comparison to normal cats (p < 0.0001 and p = 0.0001). There was no significant difference in active ghrelin concentrations between groups. Both total ghrelin and calculated desacyl ghrelin were significantly correlated with serum creatinine concentrations (p < 0.0001, r = 0.70 and p < 0.0001, r = 0.73). Elevated plasma desacyl ghrelin concentrations in cats with CKD provides evidence for dysregulation of appetite in feline CKD.

Synbiotic-IgY Therapy Modulates the Mucosal Microbiome and Inflammatory Indices in Dogs with Chronic Inflammatory Enteropathy: A Randomized, Double-Blind, Placebo-Controlled Study

Chronic inflammatory enteropathy (CE) is a common cause of persistent gastrointestinal signs and intestinal inflammation in dogs. Since evidence links dysbiosis to mucosal inflammation, probiotics, prebiotics, or their combination (synbiotics) may reduce intestinal inflammation and ameliorate dysbiosis in affected dogs. This study's aim was to investigate the effects of the synbiotic-IgY supplement on clinical signs, inflammatory indices, and mucosal microbiota in dogs with CE. Dogs with CE were enrolled in a randomized prospective trial. Twenty-four client-owned dogs were fed a hydrolyzed diet and administered supplement or placebo (diet) for 6 weeks. Dogs were evaluated at diagnosis and 2- and 6-week post-treatment. Outcome measures included clinical activity, endoscopic and histologic scores, inflammatory markers (fecal calprotectin, C-reactive protein), and composition of the mucosal microbiota via FISH. Eleven supplement- and nine placebo-treated dogs completed the trial. After 6 weeks of therapy, clinical activity and endoscopic scores decreased in both groups. Compared to placebo-treated dogs, dogs administered supplement showed decreased calprotectin at 2-week post-treatment, decreased CRP at 2- and 6-week post-treatment increased mucosal Clostridia and Bacteroides and decreased Enterobacteriaceae in colonic biopsies at trial completion. Results suggest a beneficial effect of diet and supplements on host responses and mucosal microbiota in dogs with CE.

2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats

The guidelines discuss the components of a systematic approach to nutritional management of dogs and cats. A nutritional assessment, including a body condition score and muscle condition score, is a screening evaluation that should ideally be performed at every examination. Individualized nutritional recommendations, based on the nutritional assessment, should be designed to achieve and maintain an appropriate body weight and meet nutritional requirements. Communicating nutritional recommendations to clients is a challenging aspect of nutritional management because pet owners may interpret the practice team's guidance as advocacy for a particular pet food brand or a judgment of the client's ability to properly care for the pet or of the owner's own nutritional status. The guidelines discuss approaches for effective, nonjudgmental communication of dietary recommendations to clients and strategies to increase acceptance of and adherence to veterinary nutrition recommendations. Other pet nutrition topics of current interest include recommendations for particular pet life stages, breeds, and disease conditions; risk factors for nutritional deficiencies and obesity; and considerations for home-prepared diets.

Demographics, natural history and treatment outcomes of non-molar gestational choriocarcinoma: a UK population study

OBJECTIVE

To investigate the demographics, natural history and treatment outcomes of non-molar gestational choriocarcinoma.

DESIGN

A retrospective national population-based study.

SETTING

UK 1995-2015.

POPULATION

A total of 234 women with a diagnosis of gestational choriocarcinoma, in the absence of a prior molar pregnancy, managed at the UKs two gestational trophoblast centres in London and Sheffield.

METHODS

Retrospective review of the patient's demographic and clinical data. Comparison with contemporary UK birth and pregnancy statistics.

MAIN OUTCOMES

Incidence statistics for non-molar choriocarcinoma across the maternal age groups. Cure rates for patients by FIGO prognostic score group.

RESULTS

Over the 21-year study period, there were 234 cases of non-molar gestational choriocarcinoma, giving an incidence of 1:66 775 relative to live births and 1:84 226 to viable pregnancies. For women aged under 20, the incidence relative to viable pregnancies was 1:223 494, for ages 30-34, 1:80 227, and for ages 40-45, 1:41 718. Treatment outcomes indicated an overall 94.4% cure rate. Divided by FIGO prognostic groups, the cure rates were low-risk group 100%, high-risk group 96% and ultra-high-risk group 80.5%.

CONCLUSIONS

Non-molar gestational choriocarcinoma is a very rare diagnosis with little prior detailed information on the demographics and natural history. The data in this study give age-related incidence data based on a large national population study. The results also demonstrated the widely varying natural history of this rare malignancy and the marked correlation of disease incidence with rising maternal age.

TWEETABLE ABSTRACT

National gestational choriocarcinoma database indicates a close association between increasing maternal age and incidence.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Parasitemia due to Sarcocystis neurona-like infection in a clinically ill domestic cat

An 8-year-old, 6-kg, male neutered Domestic Shorthair cat was presented to The Ohio State University Veterinary Medical Center (OSU-VMC) for difficulty breathing. Physical examination and thoracic radiographs indicated pneumonia, a soft-tissue mass in the left caudal lung lobe, and diffuse pleural effusion. The effusion was classified as modified transudate. Rare extracellular elongated (~5-7 μm × 1-2 μm) zoites with a central round to oval-shaped purple to deep purple vesicular nucleus with coarsely stippled chromatin and light blue cytoplasm were seen on a peripheral blood smear. Serum IgG and IgM were positive for Sarcocystis sp. antibodies and negative for Toxoplasma gondii antibodies, suggesting that the infection was acute rather than a recrudescence of prior infection. This organism was most consistent with either Sarcocystis neurona or Sarcocystis dasypi based on DNA sequence analysis of PCR products using COC ssRNA, ITS-1, snSAG2, and JNB25/JD396 primer sets. This is the first report to visualize by light microscopy circulating Sarcocystis sp. merozoites in the peripheral blood of a domestic cat. Therefore, Sarcocystis should be considered as a differential diagnosis in cats with suspected systemic protozoal infection.

Improving the quality of vascular surgical discharge planning in a hub centre

Introduction Discharge planning improves patient outcomes, reduces hospital stay and readmission rates, and should involve a multidisciplinary team (MDT) approach. The efficacy of MDT meetings in discharge planning was examined, as well as reasons for delayed discharge among vascular surgical inpatients. Methods Dedicated weekly MDT meetings were held on the vascular ward in Royal Derby Hospital for three months. Each patient was presented to the discharge planning meeting and an expected date of discharge was decided prospectively. Patients who were discharged after this date were considered 'delayed' and reasons for delay were explored at the next meeting. Results Overall, 193 patients were included in the study. Of these, 42 patients (22%) had a delayed discharge while 29 (15%) had an early discharge. The main reasons for delay were awaiting beds (30%), social (14%) and medical (45%). In 64%, the cause for delay was avoidable. Two-thirds (67%) of all delays were >24 hours. This totalled 115 bed days, of which 67 could have been avoided. However, 32 bed days were saved by early discharge. This equates to a net loss of 35 bed days, at a net cost of £2,936 per month or £35,235 per year. The MDT meetings also improved the quality of discharge planning; the variability between expected and actual discharge dates decreased after the first month. Conclusions Discharge planning meetings help prepare for patient discharge and are most effective with multidisciplinary input. The majority of delayed discharges from hospital are preventable. The main causes are awaiting transfers, social services input and medical reasons (eg falls). There is an obvious financial incentive to improve discharge planning. The efficiency of the MDT at discharge planning improves with time and this should therefore be continued for best results.

A team approach: implementing a model of care for preventing osteoporosis related fractures

The implementation of a multidisciplinary team-based model of care has led to significant increases in identification of patients with osteoporosis who are at risk of refracture, together with improved treatment uptake and ongoing management.

INTRODUCTION

Osteoporosis-related fractures and consequent hospital admissions are largely preventable; however, little attention has been paid to how to achieve this, in particular, through improved models of care. Presentation to emergency departments (ED) with minimal trauma fracture (MTF) provides opportunity for patients at risk to be identified, referred and managed through a systematic process ensuring prompt intervention and continuing follow-up. This study is aimed to design and implement a care model for people over 50 years of age, presenting to ED with an MTF.

METHOD

Established a multidisciplinary fracture prevention team to identify and capture at-risk patients for referral and management. Clinical data revealed the extent of lost opportunities. An electronic flagging system and data acquisition tool were developed and piloted. Established a referral pathway to detect, manage and follow-up patients, coordinated by a fracture prevention nurse.

RESULTS

Increased awareness of osteoporosis as a cause of MTF, better identification of at-risk patients across departments and services and development of a flagging and referral protocol has resulted in 100% capture of at-risk patients presented to ED. As a result there has been a significant increase in patients attending the fracture prevention clinic (FPC) (p < 0.001) from 11% in 2007 to 29% in 2008 and a significantly reduced time between fracture and when patients are seen in the FPC (p < 0.001).

CONCLUSION

A multipronged systematic team approach to identifying and capturing patients with a high risk of refracture and a dedicated nurse coordinator role has created efficiencies in the detection and management of osteoporosis.

Loss of NPC1 function in a patient with a co-inherited novel insulin receptor mutation does not grossly modify the severity of the associated insulin resistance

In Npc1 null mice, a model for Niemann Pick Disease Type C1, it has been reported that hepatocyte insulin receptor function is significantly impaired, consistent with growing evidence that membrane fluidity and microdomain structure have an important role in insulin signal transduction. However, whether insulin receptor function is also compromised in human Niemann Pick disease Type C1 is unclear. We now report a girl who developed progressive dementia, ataxia and opthalmoplegia from 9 years old, followed by severe acanthosis nigricans, hirsutism and acne at 11 years old. She was diagnosed with Niemann Pick Disease type C1 (OMIM#257220) based on positive filipin staining and reduced cholesterol-esterifying activity in dermal fibroblasts, and homozygosity for the p.Ile1061Thr NPC1 mutation. Further analysis revealed her also to be heterozygous for a novel trinucleotide deletion (c.3659 + 1_3659 + 3delGTG) at the end of exon 20 of INSR, encoding the insulin receptor, leading to deletion of Trp1193 in the intracellular tyrosine kinase domain. INSR mRNA and protein levels were normal in dermal fibroblasts, consistent with a primary signal transduction defect in the mutant receptor. Although the proband was significantly more insulin resistant than her father, who carried the INSR mutation but was only heterozygous for the NPC1 variant, their respective degrees of IR were very similar to those previously reported in a father-daughter pair with the closely related p.Trp1193Leu INSR mutation. This suggests that loss of NPC1 function, with attendant changes in membrane cholesterol composition, does not significantly modify the IR phenotype, even in the context of severely impaired INSR function.

A 7 year prospective comparative study of three topical beta blockers in the management of primary open angle glaucoma

AIM

To determine the long term efficacy of monotherapy with topically applied beta blocking agents and to determine whether selective beta blockers were able to preserve the visual field more effectively than non-selective agents.

METHOD

A prospective randomised, open, comparative study of three topically applied beta blockers-timolol, betaxolol, and carteolol-was carried out on 153 patients (280 eyes) with newly diagnosed open angle glaucoma. Those patients who were not withdrawn were followed by the same observers for a minimum of 2 years and a maximum of 7 years, with clinical observations, Goldmann tonometry and 24.2 Humphrey visual field analysis.

RESULTS

All three drugs lowered the IOP significantly from untreated levels but betaxolol took up to 12 months in some instances to reach the maximum pressure reduction. After 7 years only 43% of the eyes begun on timolol, 34% of those started on carteolol, and 29% of those on betaxolol were still being treated with these medications alone. Visual fields were analysed throughout the trial by CPSD and MD and at the end by linear regression analysis (PROGRESSOR). The visual fields remained the same without apparent improvement or deterioration throughout the period of follow up. Eight patients (11 eyes) were withdrawn because of continuing field loss in spite of reduction in IOP (six using carteolol and five using betaxolol).

CONCLUSIONS

Analysis shows that less than half the eyes initially treated with topical beta blockers might be expected to still be being treated with their original medication after 5 years. The rest required either additional medication or trabeculectomy. There was no statistically significant improvement or deterioration in the visual fields over a 7 year period. On the evidence of this trial there are no particular advantages in using selective beta blockers.

A unilateral, prolonged, nonconvulsive seizure in a patient treated with bilateral ECT

We report on a case of a 45-year-old man in an episode of major depression with psychotic features treated with bilateral electroconvulsive therapy (ECT). At the eighth treatment, he manifested unilateral, prolonged, nonconvulsive seizure activity on the left side, which lasted 351 seconds longer than seizure activity on the right, and was terminated with intravenous diazepam. This is the first report of a unilateral prolonged seizure. Its occurrence following bilateral ECT was particularly noteworthy. This case also highlights the importance of two-channel EEG recording during ECT. Without two recording channels we doubt that this event would have been detected, perhaps resulting in nonconvulsive status epilepticus.

Adverse reactions to St John's Wort

OBJECTIVE

To report 2 cases of adverse reactions to St John's wort, a popular herbal treatment for depression.

METHOD

We present 2 case histories and review the existing literature regarding St John's wort.

RESULTS

St John's wort may cause serotonin syndrome in sensitive patients. In addition, St John's wort may be associated with hair loss.

CONCLUSIONS

For clinical reasons, it is important to recognize and report adverse reactions to herbal remedies and to document that these treatments have side effects commensurate with their potent action on brain neurochemistry.

Coping and psychosocial adjustment of women with diabetes

PURPOSE

The purpose of this study was to investigate relationships between coping styles and psychosocial adjustment for women with diabetes.

METHODS

The sample consisted of 115 community-residing women with diabetes. Coping was measured by the Revised Jalowiec Coping Scale and psychosocial adjustment by the Psychosocial Adjustment to Illness Scale. Pearson's product moment correlation was used to assess relationships between coping and adjustment.

RESULTS

The most frequently and effectively used coping styles were optimistic, confrontive, self-reliant, and supportant. The psychological, social, and health care domains showed the most problems; the fewest were in the extended family, sexual, and vocational domains. Relationships were found between women's coping styles and psychosocial adjustment, with better adjustment associated with effective use of confrontive, supportant, optimistic, self-reliant, and palliative coping styles.

CONCLUSIONS

Important relationships exist between the ways women cope with diabetes and their level of psychosocial adjustment to the illness. Knowledge of these relationships can help diabetes educators assist clients in making lifestyle changes.

The effect of a high-fat meal on the oral bioavailability of the immunosuppressant sirolimus (rapamycin)

The bioavailability of an oral nonaqueous solution of sirolimus was compared under fasting conditions and after a high-fat meal in a randomized, two-way crossover pharmacokinetic study. Healthy volunteers were administered a 15 mg single dose of sirolimus on two occasions, once while fasting and once after consumption of a high-fat breakfast. Whole blood concentrations of sirolimus were assayed by using a validated method with high-performance liquid chromatography/tandem mass spectrometric detection. Sirolimus was absorbed more slowly when administered after a high-fat meal than when administered after fasting, as shown by statistically significant reductions in peak concentration (Cmax) and the ratio of Cmax to the area under the curve (AUC), and lengthening of the time to peak concentration. The oral availability of sirolimus was increased to a modest extent (35%) and in a uniform manner when administered with a high-fat meal; the geometric mean ratio of the fed/fasting AUC values was 1.35, with a 90% confidence interval of 1.26 to 1.46. Food had no effect on the terminal half-life of sirolimus (mean values of 67 to 68 hours). The 35% increase in AUC obtained after a high-fat meal appears small relative to the intersubject and intrasubject variabilities observed in clinical trials. However, to minimize unnecessary fluctuations in trough whole blood sirolimus concentrations, it is advisable that sirolimus be administered consistently in individual patients, either with or without meals.

Spiritual well-being among older adults

1. Older adults are a highly spiritual and religious group of individuals. 2. Nurses neglect spiritual interventions for older adults because of a fear of imposing their own philosophies, and lack of knowledge about the abstract. 3. Nurses need to be aware of spiritual needs not related to Judeo-Christian concepts. 4. The profound benefits to humankind of religious practice and spiritual well-being among most life forms has been reported.

The relation of ethnic identification with cigarette smoking among US urban African American and Latino youth: a pilot study

Primarily African American and Latino seventh graders (N = 545) attending health and science classes at three urban Southern California junior high schools were administered a 13-item ethnic identification assessment during one class period, to investigate the relationship between ethnic identification and tobacco use. For African Americans, the perception of looking different from other ethnic groups was found to be associated with avoidance of peer tobacco use. Among Latinos, the perception of being liked by other ethnic groups, and enjoying interaction with people outside of their ethnic group, were found to be associated with negating peer influence for tobacco use. Watching television shows with main characters of same ethnic group was associated with being able to make friends without using tobacco, for both ethnic groups. For Latinos, ever trying a cigarette was associated with the perception of being liked by other ethnic groups. These results suggest there may be elements inherent in ethnic identification protective against peer influence for smoking among ethnic minority youth. Also, acculturation of Latinos to the majority population may increase their risk for experimentation with tobacco products.

Pharmacokinetics of the aldose reductase inhibitor tolrestat: studies in healthy young and elderly male and female subjects and in subjects with diabetes

Tolrestat is an aldose reductase inhibitor undergoing clinical trials in diabetic subjects that may reduce the severity of chronic tissue damage associated with hyperglycemia. These studies were conducted to evaluate the pharmacokinetics of tolrestat in healthy young and elderly male and female subjects and in young and elderly subjects with diabetes. The drug was administered in a multiple-dose regimen, and steady-state parameters were obtained. There were no important gender-related differences, but mean values for apparent oral clearance, renal clearance, and corresponding unbound parameters were significantly lower for the elderly healthy subjects than for the young healthy subjects. The drug is highly bound to plasma proteins, and the unbound fraction (0.75%) did not differ among the subjects. The results from young and elderly diabetic subjects suggest that diabetes per se has no influence on tolrestat disposition but that there is an age-related reduction in apparent oral clearance (30 versus 18 ml/hr/kg) and a corresponding increase in the minimum steady-state plasma concentration (1.2 versus 1.9 micrograms/ml). These data indicate a possible need to reduce the dose of tolrestat in elderly subjects, assuming the same concentration-response relationship.

Dimerization of the extracellular domain of granuloycte-colony stimulating factor receptor by ligand binding: a monovalent ligand induces 2:2 complexes

Granulocyte-colony stimulating factor (G-CSF) binds to a specific cell surface receptor and induces signals for growth and differentiation in cells of granulocyte hematopoietic lineage. In order to understand how G-CSF binding initiates signals into these cells, we have studied its interactions with the entire extracellular domain of the receptor (sG-CSFR). The sG-CSFR was purified from CHO cell conditioned media with a G-CSF affinity column, resting in a preparation fully competent for ligand binding. However, when sG-CSFR was purified by conventional means, i.e., without affinity chromatography, only about half was competent. Therefore, all studies were carried out using affinity-purified material. The sG-CSFR exhibited a weak self-association into a dimer with a dissociation constant of 200microM in the absence of G-CSF. Addition of G-CSF dimerizes the receptor, with a preferred stoichiometry of 2 G-CSF molecules plus 2 receptors. Unexpectedly, receptor-receptor interactions rather than through two receptors binding to the same G-CSF molecule; i.e., G-CSF is a monovalent ligand. G-CSF binding to the receptor monomer occurs with high affinity. The binding of G-CSF also enhances the receptor-receptor dimerization; when G-CSF is bound to both receptors, dimerization is enhanced 2000-fold, while the interaction of a 1:1 receptor-ligand complex with a second ligand-free receptor is enhanced 80-fold. Thus, the mechanism of receptor dimerization is fundamentally different than that of related cytokine receptors such as growth hormone and erythropoietin receptors. Circular dichroic spectra showed a small but significant conformational change of receptor upon binding G-CSF. This is consistent with the idea that G-CSF binding alters the conformation of the receptor, resulting in an increase in receptor-receptor interactions.

Identification and characterization of a soluble c-kit receptor produced by human hematopoietic cell lines

Stem cell factor (SCF) triggers cell growth by binding to cell surface c-kit receptors. Soluble forms of several cytokine receptors have been described and may play a role in the modulation of cytokine activity in vivo. For these reasons, we investigated whether human hematopoietic cells produce soluble c-kit receptors. The human leukemia cell lines OCIM1 and MO7e display approximately 80,000 and approximately 35,000 high-affinity cell surface c-kit receptors, respectively. Soluble c-kit receptors were detected by enzyme immunoassay in OCIM1 and MO7e culture supernatants. We determined the molecular weight and binding affinity of soluble c-kit receptor produced by OCIM1 cells, soluble c-kit receptor purified from human serum, and recombinant soluble c-kit receptor expressed in CHO cells. The three soluble c-kit receptors each have a molecular weight of 98 kD. Quantitative binding experiments with 125I-SCF indicate that the soluble c-kit receptors obtained from human serum or OCIM1 cells have binding affinities for SCF of approximately 200 to 300 pmol/L, in contrast to the recombinant form, which has a binding affinity of approximately 1.5 nmol/L. All three forms of the soluble c-kit receptor were able to compete with c-kit receptors on OCIM1 cells for 125I-SCF binding. Thus human hematopoietic cells can produce a soluble form of the c-kit receptor that retains high-affinity SCF binding activity. We speculate that the soluble c-kit receptor may bind SCF and function as a receptor antagonist in vivo.

Structural requirements for addition of O-linked carbohydrate to recombinant erythropoietin

To define the structural requirements for addition of O-linked glycosylation in vivo, recombinant erythropoietin (rEPO) variants were constructed. Thirty-three independent Ser or Thr substitutions were constructed and examined to see which were subject to O-linked carbohydrate addition. Variants with Thr mutations at positions 123 and 125, but not elsewhere, contained additional carbohydrate, which suggests that several positions around the existing O-linked glycosylation site (Ser126), but not elsewhere, contain the necessary information for O-linked carbohydrate addition. Two forms of the Thr125 variant were identified. One form was glycosylated only at residue 125, and a second form was glycosylated at both Thr125 and Ser126, the normal O-glycosylation site. We have also found that glycosylation is less efficient when rEPO is improperly folded and that prolines at -1 and +1 relative to the O-glycosylation site enhance glycosylation.

Social isolation does not alter brain regional benzodiazepine binding site numbers, affinity and coupling in the rat

Male Sprague-Dawley rats were differentially housed for 21 days immediately after weaning. Isolated animals showed a selective suppression of exploration of the light side of a two compartment box; spending significantly less time in the light, and making fewer transitions between the light and dark compartments compared to socially reared controls. However, both basal and GABA-stimulated [3H] flunitrazepam binding was unaltered in the frontal cortex, hippocampus, amygdala and cerebellum following social isolation. These results are discussed in relation to other studies on central benzodiazepine receptor changes following a variety of experimental stressors.

Deficits in exploratory behaviour in socially isolated rats are not accompanied by changes in cerebral cortical adrenoceptor binding

Social isolation of rats produces marked deficits in exploratory behaviour in a novel environment. To test our hypothesis that adrenoceptors are modified by social isolation we have measured alpha 2- and beta-adrenoceptor binding in the cerebral cortex of rats isolated for 21 days starting immediately after weaning. After this period the animals showed a significant reduction in exploration in the elevated X-maze and increased avoidance of bright light in a two-compartment shuttlebox. There were no changes in adrenoceptor binding at this time, however. The implications of these findings are discussed.

Memory disturbance after stroke: frequency and associated losses

138 patients who survived an acute stroke had their memory assessed at 3 months. As a group these patients had no impairment of digit span when compared with published age-matched normal data. Immediate logical memory (of a story) was poor in 29 per cent, and 14 per cent could not draw a picture immediately after seeing it. Poor memory function was not associated with more severe strokes, but was associated with poor functional ability on everyday tasks. Poor visual recall was associated with lower abilities at ADL, independent of any effect of age. Statistically significant recovery was detected in immediate logical memory and visual recall between 3 and 6 months.

Identification of DNA sequences required for transcription of the human alpha 1-globin gene in a new SV40 host-vector system

We have developed a rapid and simple method for studying the transcription of cloned eucaryotic genes, which involves transfecting SV40-transformed monkey cell lines (COS cells) with derivatives of the plasmid pBR322 that contain the SV40 viral replication origin but lack regions necessary for viral transcription (SV-ORI vectors). Because COS cells produce SV40 T antigen and are permissive for SV40 viral replication, transfected SV-ORI plasmids replicate to a high copy number. SV-ORI plasmids carrying a human alpha-globin gene are also replicated in COS cells. Moreover, the alpha-globin gene is faithfully transcribed to produce high levels of RNA, which is accurately processed to produce authentic alpha-globin mRNA. We have used this transcription system to demonstrate that a sequence located between 55 and 87 base pairs upstream from the mRNA capping site is required for efficient transcription of the alpha-globin gene in COS cells.

Casting light on Darwin's ape at Queen's University

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New library buildings: Bracken Library, Queen's University, Kingston, Ontario, Canada

A brief sketch is given of the past history and present functions of the Bracken Library. Architectural and decorative features of the new library are described.

Cot deaths and water-sodium

Over a thirty-year period in Scunthorpe, during which there were two changes in the sodium content of the water supply, there were significantly more sudden deaths in infancy during the decade when sodium levels were highest. This is compatible with the hypothesis that hypernatraemia is a factor leading to cot death. Changes in the incidence of breastfeeding over the same period may have contributed to, but are unlikely to account for, the result because the pattern was different in a neighbouring district where there was no change in water quality.

Excretion of non-conjugated androstenedione and testosterone in human urine

A method for the measurement of unconjugated testosterone and androstenedione in human urine is described. The method uses chromatographic separation followed by radioimmunoassay and has been examined for reliability. The mean 24-hour excretion of androstenedione by adult male subjects was 2.5 mug and of testosterone was 0.8 mug. For women, the mean excretion was 2.9 mug of androstenedione and 0.25 mug of testosterone. In pregnancy, androstenedione excretion was occasionally elevated above the normal range, but testosterone excretion was quite commonly increased. Some hirsute subjects exhibited an increase in androstenedione excretion, which was decreased by administration of dexamethasone. The results suggest that the amount of unconjugated testosterone in urine is not a direct reflection of the plasma free testosterone, but urinary androstenedione may be a useful reflection of plasma androstenedione levels.

Genetic analysis of heterogeneous DNA circles formed after prophage Mu induction

Induction of a Mu prophage in Escherichia coli Hfr strains lyosgenic for Mu cts62 leads to the generation of F' episomes. Each episome thus formed carries at least one copy of the Mu genome. These results suggest that integration of Mu is mandatory for the formation of the heterogeneous circles during the lytic cycle. The circles may be precursors for phage maturation.