Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

20 Armoured Infantry Brigade downgrade study: epidemiology of principal conditions and plugging leaks in the rehabilitation pipeline

Introduction

In April 2017, 22% of Army Full-time Trade Trained Strength was downgraded, reducing fully deployable strength to 60 546, against a target of 82 000. In June 2017, Commander 20 Armoured Infantry Brigade (20 AI Bde) initiated a study to look at the principal conditions causing medical downgrading, as a stepping stone to finding ways of reducing injury, enhancing rehabilitation and improving deployability.

Method

The Defence Medical Information Capability Programme medical records for every downgraded soldier in 20 AI Bde and supporting units were scrutinised to identify their Medical Deployment Standard and the primary condition causing downgrading.

Results

A total of 842 downgraded soldiers were identified from a held strength of 3827 personnel. Sixty-five per cent of these downgrades were due to musculoskeletal injury (MSKI). Of this 65%, the majority were due to knee (31%), spine (28%) and foot/ankle (23%). Of the remaining 35%, the majority were due to noise-induced hearing loss (NIHL) (22%), adjustment disorders (19%) and non-freezing cold injury (NFCI) (13%).

Several factors that slowed an individual’s recovery pathway were identified. They mainly relate to soldiers being lost to follow-up through lack of active case management.

Conclusions

MSKI is responsible for most downgraded personnel at Brigade level. The distribution of principal conditions is similar to previous studies looking at recruits and individual units.

The creation of a rehabilitation troop, delivering active case management, can reduce the number of soldiers leaking out of the rehabilitation pipeline.

Updated Diploma in Immediate Medical Care: applicability to military and civilian clinicians

The Diploma in Immediate Medical Care (DipIMC) is the entry-level interprofessional civilian qualification for prehospital emergency care (PHEC) in the UK. It is designed to test the knowledge, skills and behaviours of PHEC practitioners. Military personnel are eligible to enter, dependent on the level of PHEC experience they have. The DipIMC examination has changed in recent years; this paper aims to update aspiring candidates on the application process, recommended preparation and skill-set required to pass.

Thrombocytosis as a Marker for Postoperative Complications in Colorectal Surgery

BACKGROUND

Blood platelet measurement is a widely available and inexpensive test that is performed routinely. Platelets are thought to act by inducing inflammation and play a role in clotting and antimicrobial defence. A postoperative rise in the platelet count (thrombocytosis) is often dismissed as an incidental finding, but there is growing evidence to suggest that it may act as an indicator to underlying pathology. It correlates with significant pyogenic infections as well as multiple malignancies. In addition to this, recent research indicates that thrombocytosis may be a useful prognostic indicator for postoperative outcomes in patients with malignancies. In patients undergoing surgery for gastric cancer, a combination of platelet count and neutrophil-to-lymphocyte (NLR) ratio collected preoperatively was shown to correlate with postoperative survival.

OBJECTIVE

To evaluate whether there is a positive correlation between pre- and postoperative thrombocytosis and the risk of complications following colorectal surgery.

METHODS

This was a retrospective observational study based in Morriston Hospital, Swansea. Patients undergoing elective colorectal surgery for an 18-month period between 2014 and 2016 were included. Data on patient demographics, pre- and postoperative platelet count, the first date at which the highest platelet count was recorded, length of stay, type of operation, and postoperative complications using the Clavien-Dindo classification was obtained from the theatre booking software (TOMS) and Welsh Clinical Portal. Pearson's chi-square test was used for the analysis of the categorical variables.

RESULTS

Of the 201 patients studied, 75 (37%) had postoperative thrombocytosis (platelets ≥ 500 × 109/L, range 501-1136), 120 (59%) had postoperative normocytosis (platelets < 500 × 109/L, range 107-499), and 6 (2.9%) patients were excluded due to insufficient data. Peak platelet level was seen at a median of 8 days postoperatively but ranged from days 1 to 49. In patients with thrombocytosis, the mean time to peak platelet count was 9.5 days and ranged 1 to 49 days. 101/195 (52%) patients had a Clavien-Dindo III/V postoperative complication: 63% patients with postoperative normocytosis and 24% with postoperative thrombocytosis. In the thrombocytosis group, 16/75 (21%) were found to have postoperative pelvic collections compared to 1/120 (0.8%) of the normocytic patients. The total percentage of medical complications (44% versus 20%, p = 0.006) and surgical complications (64% versus 15.8%, p = 0.0001) was higher in the thrombocytosis group compared to the normocytosis group.

CONCLUSION

In this retrospective study, thrombocytosis was shown to have a positive correlation with postoperative medical and surgical complications. An elevated platelet count in the postoperative period should alert the clinician to a developing complication. We recommend that further studies with a larger sample size would test the specific associations with individual complications.

The prevalence and potential determinants of dysmenorrhoea and other pelvic pain in women: a prospective study

OBJECTIVE

To estimate the prevalence of pelvic pain and model associations with potential demographic, obstetric, gynaecological and psychosocial determinants.

DESIGN, SETTING AND SAMPLE

A cohort study of women born between 1972 and 1973 in Dunedin, New Zealand, most recently assessed when aged 38 years (95% of survivors retained); 429 women were eligible for analysis.

METHODS

Women self-completed reproductive health questionnaires at ages 21, 26, 32 and 38 years, with questions on dysmenorrhoea at ages 13 and 15, and on all pelvic pain at age 38. Prevalence and 95% confidence intervals (CI) were calculated and Poisson regression used to model associations.

MAIN OUTCOME MEASURES

The prevalence of pain and adjusted relative risks (ARR) for potential explanatory factors.

RESULTS

Over half (54.5%, 95% CI 49.7-59.3%) of women experienced pelvic pain in the past 12 months at age 38. Dysmenorrhoea was reported by 46.2% (41.3-51.3%), dyspareunia by 11.6% (8.7-15.2%) and other pelvic pain (OPP) by 17.3% (13.8-21.2%). After adjusting for multiple factors, pregnancy (ARR 0.60, 95% CI 0.32-1.13) and childbirth (ARR 0.52, 95% CI 0.25-1.09) were borderline protective for dyspareunia and OPP, respectively. However, childbirth was not associated with dysmenorrhoea (ARR 0.97, 95% CI 0.74-1.28). Dysmenorrhoea and dyspareunia were strongly associated, and both were associated with endometriosis.

CONCLUSIONS

Our data confirm that female pelvic pain is common, and suggest common gynaecological and obstetric causal pathways, but there was no strong evidence supporting a benefit of childbirth for dysmenorrhoea. Further research on obstetric events and pelvic pain is needed, with both being common experiences.

TWEETABLE ABSTRACT

Pelvic pain was common at age 38, especially dysmenorrhoea (46.2%), and no improvement was detected following childbirth.

Distraction during Deployment: Marital Relationship Associations with Spillover for Deployed Army Soldiers

Military spouses often have concerns regarding the impact of their communication on soldiers during deployment. However, literature is mixed regarding how communication between soldiers and spouses may impact soldiers' self-reported work functioning during deployment, suggesting the need to evaluate moderating factors. In the current study, three relationship factors (marital satisfaction, conflictual communication, and proportion of conversation focused on problems) were tested as moderators of communication frequency and negative marriage-to-work spillover for soldiers. Whereas the three relationship factors were independently related to negative spillover, none significantly moderated the relationship between communication frequency and spillover. The overall pattern of results suggests that (a) lower marital satisfaction, a focus on problems during communication, and conflictual communication are each strongly linked to spillover for deployed soldiers, and (b) military couples may be self-restricting deployment communication frequency when experiencing less marital satisfaction and higher rates of negative communication. Implications for communication during deployment are discussed.

A Coordinated Effort to Manage Soybean Rust in North America: A Success Story in Soybean Disease Monitoring

Existing crop monitoring programs determine the incidence and distribution of plant diseases and pathogens and assess the damage caused within a crop production region. These programs have traditionally used observed or predicted disease and pathogen data and environmental information to prescribe management practices that minimize crop loss. Monitoring programs are especially important for crops with broad geographic distribution or for diseases that can cause rapid and great economic losses. Successful monitoring programs have been developed for several plant diseases, including downy mildew of cucurbits, Fusarium head blight of wheat, potato late blight, and rusts of cereal crops. A recent example of a successful disease-monitoring program for an economically important crop is the soybean rust (SBR) monitoring effort within North America. SBR, caused by the fungus Phakopsora pachyrhizi, was first identified in the continental United States in November 2004. SBR causes moderate to severe yield losses globally. The fungus produces foliar lesions on soybean (Glycine max) and other legume hosts. P. pachyrhizi diverts nutrients from the host to its own growth and reproduction. The lesions also reduce photosynthetic area. Uredinia rupture the host epidermis and diminish stomatal regulation of transpiration to cause tissue desiccation and premature defoliation. Severe soybean yield losses can occur if plants defoliate during the mid-reproductive growth stages. The rapid response to the threat of SBR in North America resulted in an unprecedented amount of information dissemination and the development of a real-time, publicly available monitoring and prediction system known as the Soybean Rust-Pest Information Platform for Extension and Education (SBR-PIPE). The objectives of this article are (i) to highlight the successful response effort to SBR in North America, and (ii) to introduce researchers to the quantity and type of data generated by SBR-PIPE. Data from this system may now be used to answer questions about the biology, ecology, and epidemiology of an important pathogen and disease of soybean.

Extension plant pathology: strengthening resources to continue serving the public interest

Extension plant pathologists deliver science-based information that protects the economic value of agricultural and horticultural crops in the United States by educating growers and the general public about plant diseases. Extension plant pathologists diagnose plant diseases and disorders, provide advice, and conduct applied research on local and regional plant disease problems. During the last century, extension plant pathology programs have adjusted to demographic shifts in the U.S. population and to changes in program funding. Extension programs are now more collaborative and more specialized in response to a highly educated clientele. Changes in federal and state budgets and policies have also reduced funding and shifted the source of funding of extension plant pathologists from formula funds towards specialized competitive grants. These competitive grants often favor national over local and regional plant disease issues and typically require a long lead time to secure funding. These changes coupled with a reduction in personnel pose a threat to extension plant pathology programs. Increasing demand for high-quality, unbiased information and the continued reduction in local, state, and federal funds is unsustainable and, if not abated, will lead to a delay in response to emerging diseases, reduce crop yields, increase economic losses, and place U.S. agriculture at a global competitive disadvantage. In this letter, we outline four recommendations to strengthen the role and resources of extension plant pathologists as they guide our nation's food, feed, fuel, fiber, and ornamental producers into an era of increasing technological complexity and global competitiveness.

Efficacy and Stability of Integrating Fungicide and Cultivar Resistance to Manage Fusarium Head Blight and Deoxynivalenol in Wheat

Integration of host resistance and prothioconazole + tebuconazole fungicide application at anthesis to manage Fusarium head blight (FHB) and deoxynivalenol (DON) in wheat was evaluated using data from over 40 trials in 12 U.S. states. Means of FHB index (index) and DON from up to six resistance class-fungicide management combinations per trial (susceptible treated [S_TR] and untreated [S_UT]; moderately susceptible treated [MS_TR] and untreated [MS_UT]; moderately resistant treated [MR_TR] and untreated [MR_UT]) were used in multivariate meta-analyses, and mean log response ratios across trials were estimated and transformed to estimate mean percent control ( ) due to the management combinations relative to S_UT. All combinations led to a significant reduction in index and DON (P < 0.001). MR_TR was the most effective combination, with a of 76% for index and 71% for DON, followed by MS_TR (71 and 58%, respectively), MR_UT (54 and 51%, respectively), S_TR (53 and 39%, respectively), and MS_UT (43 and 30%, respectively). Calculations based on the principle of treatment independence showed that the combination of fungicide application and resistance was additive in terms of percent control for index and DON. Management combinations were ranked based on percent control relative to S_UT within each trial, and nonparametric analyses were performed to determine management combination stability across environments (trials) using the Kendall coefficient of concordance (W). There was a significant concordance of management combinations for both index and DON (P < 0.001), indicating a nonrandom ranking across environments and relatively low variability in the within-environment ranking of management combinations. MR_TR had the highest mean rank (best control relative to S_UT) and was one of the most stable management combinations across environments, with low rank stability variance (0.99 for index and 0.67 for DON). MS_UT had the lowest mean rank (poorest control) but was also one of the most stable management combinations. Based on Piepho's nonparametric rank-based variance homogeneity U test, there was an interaction of management combination and environment for index (P = 0.011) but not for DON (P = 0.147), indicating that the rank ordering for index depended somewhat on environment. In conclusion, although the magnitude of percent control will likely vary among environments, integrating a single tebuconazole + prothioconazole application at anthesis with cultivar resistance will be a more effective and stable management practice for both index and DON than either approach used alone.

High prevalence of diabetes and pre-diabetes in adults with Williams syndrome

A standard oral glucose tolerance test (OGTT) was administered to 28 adults with Williams syndrome (WS). Three quarters of the WS subjects showed abnormal glucose curves, meeting diagnostic criteria for either diabetes or the pre-diabetic state of impaired glucose tolerance. Fasting mean glucose and median insulin levels did not differ significantly in the total WS cohort versus age-gender-BMI matched controls, though the glucose area under the curve was greater in the WS subjects. HbA1c levels were not as reliable as the OGTT in diagnosing the presence of diabetes. Given the high prevalence of impaired glucose regulation, adults with WS should be screened for diabetes, and when present should be treated in accordance with standard medical practice. Hemizygosity for a gene mapping to the Williams syndrome chromosome region (WSCR) is likely the major factor responsible for the high frequency of diabetes in WS. Syntaxin-1A is a prime candidate gene based on its location in the WSCR, its role in insulin release, and the presence of abnormal glucose metabolism in mouse models with aberrantly expressed Stx-1a.

First Report of Ascochyta Blight of Field Pea Caused by Ascochyta pisi in South Dakota

Tan lesions approximately 1.7 × 0.8 cm with distinct dark brown margins and small pycnidia were observed on leaves of field peas (Pisum sativum L. 'Agassiz') growing in Campbell County, South Dakota (45°45.62'N, 100°9.13'W) in July 2008. Small pieces of symptomatic leaves were surface sterilized (10% NaOCl for 1 min, 70% EtOH for 1 min, and sterile distilled H₂O for 2 min) and placed on potato dextrose agar (PDA) for 7 days under fluorescent lights with a 12-h photoperiod to induce sporulation. A pure culture was established by streaking a conidial suspension on PDA and isolating a single germinated spore 3 days later. The culture was grown on clarified V8 media for 10 days. Conidia were 10 to 16 × 3 to 4.5 μm and uniseptate with a slightly constricted septum, similar to those of Ascochyta pisi Lib. The exuding spore mass from pycnidia growing on the medium was carrot red. No chlamydospores or pseudothecia were observed (1,2). To confirm the identity of A. pisi, DNA was extracted from the lyophilized mycelium of the 10-day-old culture with the DNeasy Plant Mini Kit (Qiagen, Valencia, CA). Internal transcribed spacer (ITS) regions I and II were amplified with PCR primers ITS 5 and ITS 4 (3). PCR amplicons were cleaned and directly sequenced in both directions using the primers. A BLASTN search against the NCBI nonredundant nucleotide database was performed using the consensus sequence generated by alignment of the forward and reverse sequences for this region. The consensus sequence (GenBank Accession No. GU722316) most closely matched A. pisi var. pisi strain (GenBank Accession No. EU167557). These observations confirm the identity of the fungus as A. pisi. A suspension of 1 × 10⁶ conidia/ml of the isolate was spray inoculated to runoff on 10 replicate plants of 2-week-old, susceptible green field pea 'Sterling'. Plants were incubated in a dew chamber for 48 h at 18°C and moved to the greenhouse bench where they were maintained at 20 to 25°C with a 12-h photoperiod for 1 week. Tan lesions with dark margins appeared 7 days after inoculation and disease was assessed after 10 days (4). No symptoms were observed on water-treated control plants. A. pisi was reisolated from lesions and confirmed by DNA sequencing of the ITS region, fulfilling Koch's postulates. Currently, states bordering South Dakota (North Dakota and Montana) lead the United States in field pea production. Although acreage is limited in South Dakota, the identification of A. pisi in this region is serious. The disease is yield limiting and foliar fungicides are used for disease management (1). To our knowledge, this is the first report of Ascochyta blight on P. sativum caused by A. pisi occurring in South Dakota and the MonDak production region (the Dakotas and Montana). References: (1) T. W. Bretag et al. Aust. J. Agric. Res. 57:88, 2006. (2) A. S. Lawyer. Page 11 in: The Compendium of Pea Diseases. D. J. Hagedorn, ed. The American Phytopathological Society, St Paul, MN, 1984. (3) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990. (4) J. M. Wroth. Can. J. Bot. 76:1955, 1998.

A Distributed Lag Analysis of the Relationship Between Gibberella zeae Inoculum Density on Wheat Spikes and Weather Variables

ABSTRACT In an effort to characterize the association between weather variables and inoculum of Gibberella zeae in wheat canopies, spikes were sampled and assayed for pathogen propagules from plots established in Indiana, North Dakota, Ohio, Pennsylvania, South Dakota, and Manitoba between 1999 and 2005. Inoculum abundance was quantified as the daily number of colony forming units per spike (CFU/spike). A total of 49 individual weather variables for 24-h periods were generated from measurements of ambient weather data. Polynomial distributed lag regression analysis, followed by linear mixed model analysis, was used to (i) identify weather variables significantly related to log-transformed CFU/spike (the response variable; Y), (ii) determine the time window (i.e., lag length) over which each weather variable affected Y, (iii) determine the form of the relationship between each weather variable and Y (defined in terms of the polynomial degree for the relationship between the parameter weights for the weather variables and the time lag involved), and (iv) account for location-specific effects and random effects of years within locations on the response variable. Both location and year within location affected the magnitude of Y, but there was no consistent trend in Y over time. Y on each day was significantly and simultaneously related to weather variables on the day of sampling and on the 8 days prior to sampling (giving a 9-day time window). The structural relationship corresponded to polynomial degrees of 0, 1, or 2, generally showing a smooth change in the parameter weights and time lag. Moisture- (e.g., relative humidity-) related variables had the strongest relationship with Y, but air temperature- and rainfall-related variables also significantly affected Y. The overall marginal effect of each weather variable on Y was positive. Thus, local weather conditions can be utilized to improve estimates of spore density on wheat spikes around the time of flowering.

Forward genetic screen of mouse reveals dominant missense mutation in the P/Q-type voltage-dependent calcium channel, CACNA1A

Dominant mutations of the P/Q-type Ca(2+) channel (CACNA1A) underlie several human neurological disorders, including episodic ataxia type 2, familial hemiplegic migraine 1 (FHM1) and spinocerebellar ataxia 6, but have not been found previously in the mouse. Here we report the first dominant ataxic mouse model of Cacna1a mutation. This Wobbly mutant allele of Cacna1a was identified in an ethylnitrosourea (ENU) mutagenesis dominant behavioral screen. Heterozygotes exhibit ataxia from 3 weeks of age and have a normal life span. Homozygotes have a righting reflex defect from postnatal day 8 and later develop severe ataxia and die prematurely. Both heterozygotes and homozygotes exhibit cerebellar atrophy with focal reduction of the molecular layer. No obvious loss of Purkinje cells or decrease in size of the granule cell layer was observed. Real-time polymerase chain reaction revealed altered expression levels of Cacna1g, Calb2 and Th in Wobbly cerebella, but Cacna1a messenger RNA and protein levels were unchanged. Positional cloning revealed that Wobbly mice have a missense mutation leading to an arginine to leucine (R1255L) substitution, resulting in neutralization of a positively charged amino acid in repeat III of voltage sensor segment S4. The dominance of the Wobbly mutation more closely resembles patterns of CACNA1A mutation in humans than previously described mouse recessive mutants (tottering, leaner, rolling Nagoya and rocker). Positive-charge neutralization in S4 has also been shown to underlie several cases of human dominant FHM1 with ataxia. The Wobbly mutant thus highlights the importance of the voltage sensor and provides a starting point to unravel the neuropathological mechanisms of this disease.

A 1.5 million-base pair inversion polymorphism in families with Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is most often caused by hemizygous deletion of a 1.5-Mb interval encompassing at least 17 genes at 7q11.23 (refs. 1,2). As with many other haploinsufficiency diseases, the mechanism underlying the WBS deletion is thought to be unequal meiotic recombination, probably mediated by the highly homologous DNA that flanks the commonly deleted region. Here, we report the use of interphase fluorescence in situ hybridization (FISH) and pulsed-field gel electrophoresis (PFGE) to identify a genomic polymorphism in families with WBS, consisting of an inversion of the WBS region. We have observed that the inversion is hemizygous in 3 of 11 (27%) atypical affected individuals who show a subset of the WBS phenotypic spectrum but do not carry the typical WBS microdeletion. Two of these individuals also have a parent who carries the inversion. In addition, in 4 of 12 (33%) families with a proband carrying the WBS deletion, we observed the inversion exclusively in the parent transmitting the disease-related chromosome. These results suggest the presence of a newly identified genomic variant within the population that may be associated with the disease. It may result in predisposition to primarily WBS-causing microdeletions, but may also cause translocations and inversions.

A phase I trial of amsalog (CI-921) administered by intravenous infusion using a 5-day schedule

PURPOSE

Amsalog, a derivative of 9-aminoacridine, is an inhibitor of topoisomerase II. Early studies of intravenous amsalog administered either once weekly, or daily for 3 days repeated every 3 weeks, showed that myelosuppression is the dose-limiting toxicity (DLT). Phase II studies showed only limited activity in breast, head and neck, and non-small-cell lung cancer. The activity of other topoisomerase inhibitors is schedule-dependent. We therefore performed a phase I study to evaluate the use of amsalog on a more prolonged schedule.

METHODS

A group of 19 patients with refractory malignancies were treated in six cohorts using 2-h infusions of amsalog daily for 5 days, repeated every 3 weeks.

RESULTS

Myelosuppression was seen as DLT at 200 mg/m2 per day. Other toxicities included nausea and vomiting, fatigue, and, when administered via a peripheral venous line, severe phlebitis necessitating administration via an indwelling central venous catheter for doses greater than 100 mg/m2. Pharmacokinetic studies showed a linear relationship between Cmax and AUC, and dose. The terminal half-life was 2 h, consistent with previous studies.

CONCLUSION

We conclude that amsalog can be safely given on a 5-day schedule every 3 weeks at doses up to 200 mg/m2. The dose recommended for further studies is 180 mg/m2 per day for 5 days repeated every 3 weeks. However, in view of the phlebitis, which necessitated the use of central venous catheters for administration, other routes of administration, for example oral formulations, should be explored.

Elastin: mutational spectrum in supravalvular aortic stenosis

Supravalvular aortic stenosis (SVAS) is a congenital narrowing of the ascending aorta which can occur sporadically, as an autosomal dominant condition, or as one component of Williams syndrome. SVAS is caused by translocations, gross deletions and point mutations that disrupt the elastin gene (ELN) on 7q11.23. Functional hemizygosity for elastin is known to be the cause of SVAS in patients with gross chromosomal abnormalities involving ELN. However, the pathogenic mechanisms of point mutations are less clear. One hundred patients with diagnosed SVAS and normal karyotypes were screened for mutations in the elastin gene to further elucidate the molecular pathology of the disorder. Mutations associated with the vascular disease were detected in 35 patients, and included nonsense, frameshift, translation initiation and splice site mutations. The four missense mutations identified are the first of this type to be associated with SVAS. Here we describe the spectrum of mutations occurring in familial and sporadic SVAS and attempt to define the mutational mechanisms involved in SVAS. SVAS shows variable penetrance within families but the progressive nature of the disorder in some cases, makes identification of the molecular lesions important for future preventative treatments.

Purified hematopoietic stem cells can differentiate into hepatocytes in vivo

The characterization of hepatic progenitor cells is of great scientific and clinical interest. Here we report that intravenous injection of adult bone marrow cells in the FAH(-/-) mouse, an animal model of tyrosinemia type I, rescued the mouse and restored the biochemical function of its liver. Moreover, within bone marrow, only rigorously purified hematopoietic stem cells gave rise to donor-derived hematopoietic and hepatic regeneration. This result seems to contradict the conventional assumptions of the germ layer origins of tissues such as the liver, and raises the question of whether the cells of the hematopoietic stem cell phenotype are pluripotent hematopoietic cells that retain the ability to transdifferentiate, or whether they are more primitive multipotent cells.

Detection of an atypical 7q11.23 deletion in Williams syndrome patients which does not include the STX1A and FZD3 genes

We present two patients with the full Williams syndrome (WS) phenotype carrying a smaller deletion than typically observed. The deleted region spans from the elastin gene to marker D7S1870. This observation narrows the minimal region of deletion in WS and suggests that the syntaxin 1A and frizzled genes are not responsible for the major features of this developmental disorder and provides important insight into understanding the genotype-phenotype correlation in WS.

Identification of a putative transcription factor gene (WBSCR11) that is commonly deleted in Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a complex developmental disorder involving the hemizygous deletion of genes on chromosome 7q11.23. The cardiovascular aspects of the disorder are known to be caused by haploinsufficiency for ELN, but the genes contributing to the other features of WBS are still undetermined. Fifteen genes have been shown to reside within the WBS deletion, and here we report the identification and cloning of an additional gene that is commonly deleted. WBSCR11, which was identified through genomic DNA sequence analysis and cDNA library screening, was positioned toward the telomeric end of the WBS deletion. The gene is expressed in all adult tissues analyzed, including many regions of the brain. The predicted protein displays homology to another gene from the WBS deletion, GTF2I, which is known to be a transcription factor. We postulate that WBSCR11 is also a transcription factor and may contribute to the spectrum of developmental symptoms found in WBS.

Quantitation of the proliferative potential of highly enriched human primitive hematopoietic progenitor cells using a stroma-free limiting dilution assay with automated scoring

BACKGROUND

Increasing use of phenotypically-enriched stem cell populations for clinical hematopoietic transplants has led to an urgent demand for a reliable, rapid and simple functional assay which would provide an estimation of the reconstituting potential of cells prior to transplantation.

METHODS

We have developed a 2-week quantitative, stroma-free assay to measure the frequency of primitive progenitors within hematopoietic cell samples. This relatively short-term assay provides frequency information which correlates with that measured by a 5-week stroma-dependent CAFC assay. Cells with the phenotype CD34+Thy-1+ were purified by fluorescence-activated cell sorting from peripheral blood apheresis products of multiple myeloma patients mobilized with cytoxan and GM-CSF. CD34+Thy-1+ cells were plated at limiting dilution into microtiter wells and cultured in an Iscove's based serum-deprived culture medium, supplemented with the cytokines, interleukin (IL)-3, IL-6, G-CSF, Flk2/Flt3 ligand (FL) and Kit ligand (KL). After 2 weeks, cell proliferation in individual wells was quantified by microscopy and bright-field imaging, or by using a fluorescent nucleic acid-binding dye and fluorimetry. Poisson statistics were used to calculate the frequency of wells containing cells with high proliferative potential (wells containing > or = 500 cells).

RESULTS

Progenitor cell frequencies generated using this assay were compared by linear regression analysis to those generated from 32 parallel CAFC and CFU-C assays performed on the same patient samples. Correlations were r = 0.80, r2 = 0.65, and r = 0.76, r2 = 0.58, respectively; these correlations were highly significant (p < 10(-7)).

DISCUSSION

This limiting dilution assay should more directly quantitate the potential of primitive hematopoietic cells than a CFU-C assay. It also has advantages over both the CAFC and the CFU-C assay, in that scoring has been automated, making it simple, rapid, and objective compared with manual cobblestone area or colony counting. The described limiting dilution assay may provide a useful alternative to assays currently used to evaluate the viability and proliferative potential of purified hematopoietic cells intended for transplant.

The BCL7 gene family: deletion of BCL7B in Williams syndrome

The BCL7A gene, which maps to human chromosome 12q24.13, was cloned through its direct involvement with MYC and IGH in a three-way translocation in a Burkitt lymphoma cell line. Here, we describe the identification of two related human genes, BCL7B and BCL7C, which share 90% identity to the amino-terminal 51 amino acids of human BCL7A, as well as 41% identity in the same region to Drosophila melanogaster, Caenorhabditis elegans, and Brugia malayi EST sequences. This degree of relatedness in the amino-terminal domain suggests we have defined a new gene family of unknown function. There was little sequence conservation between the family members outside this conserved domain and no identified protein motifs could be deduced. Human BCL7B and BCL7C mapped to chromosome 7q11.23, and 16p11, respectively. No chromosomal rearrangements affecting BCL7B or BCL7C were detected in lymphoid malignancies. BCL7B did, however, map within the region of 7q11.23 which is commonly deleted in the congenital disorder, Williams syndrome.

PMS2-related genes flank the rearrangement breakpoints associated with Williams syndrome and other diseases on human chromosome 7

The human PMS2 mismatch repair gene and a family of at least 17 other related genes (named human PMSR or PMS2L genes) have been localized to human chromosome 7. Human PMS2 has been mapped previously to 7p22 and shown to be causative in hereditary nonpolyposis colon cancer (HNPCC), but the human PMS2L genes have not been positioned in the context of the physical or genetic map of chromosome 7. In this study we have used various mapping methodologies to determine the precise location of the human PMS2L genes at 7q11.22, 7q11.23, and 7q22. Within 7q11.23, human PMS2L genes were found to be present at at least three sites as part of duplicated genomic segments that flank the most common rearrangement breakpoints in Williams syndrome.

Resources for human genetics on the World Wide Web

A little over a century ago, the HMS Beagle sailed the Pacific Ocean bringing Charles Darwin to the perfect environment in which to piece together his observations forming the theory of evolution. Now, geneticists and laypeople alike surf the equally formidable waters of the internet in search of enlightenment. Here, we attempt to help you navigate towards resources for human genetics by providing maps to three destinations: The Human Genome Project (Box 1), education (Box 2), and human genetic diseases (Box 3). For each, we highlight a few sites that we consider are the most informative and original. A more extensive list containing other useful sites has been compiled and posted on a 'jump site' at: http:/(/)www.cgdn.generes.ca/.

Identification of genes from a 500-kb region at 7q11.23 that is commonly deleted in Williams syndrome patients

Williams syndrome (WS) is a multisystem developmental disorder caused by the deletion of contiguous genes at 7q11.23. Hemizygosity of the elastin (ELN) gene can account for the vascular and connective tissue abnormalities observed in WS patients, but the genes that contribute to features such as infantile hypercalcemia, dysmorphic facies, and mental retardation remain to be identified. In addition, the size of the genomic interval commonly deleted in WS patients has not been established. In this study we report the characterization of a 500-kb region that was determined to be deleted in our collection of WS patients. A detailed physical map consisting of cosmid, P1 artificial chromosomes, and yeast artificial chromosomes was constructed and used for gene isolation experiments. Using the techniques of direct cDNA selection and genomic DNA sequencing, three known genes (ELN, LIMK1, and RFC2), a novel gene (WSCR1) with homology to RNA-binding proteins, a gene with homology to restin, and four other putative transcription units were identified. LIMK1 is a protein kinase with two repeats of the LIM/double zinc finger motif, and it is highly expressed in brain. RFC2 is the 40-kDa ATP-binding subunit of replication factor C, which is known to play a role in the elongation of DNA catalyzed by DNA polymerase delta and epsilon. LIMK1 and WSCR1 may be particularly relevant when explaining cognitive defects observed in WS patients.

Molecular definition of a narrow interval at 7q22.1 associated with myelodysplasia

Chromosome 7 translocations, deletions, or monosomy are associated with myelodysplasia (MDS) and acute myeloid leukemia both in children and adults. These chromosomal anomalies represent one of the most common cytogenetic abnormalities associated with these diseases and usually herald a poor prognosis. In this study two cosmid DNA probes that mapped to 7q22.1 and were known to be separated by approximately 500 kb were identified to flank the proximal inversion breakpoint in a patient carrying a constitutional inversion (7q22.1-34) associated with MDS. A yeast artificial chromosome (YAC) clone that encompassed the two cosmids was identified and shown to span the breakpoint. Fluorescence in situ hybridization was then used to analyze six additional patients with myelodysplasia and chromosomal rearrangements of the 7q22 region (three patients had translocations and three carried deletions). The breakpoint in one of the patients was found to be contained within the same YAC clone that spanned the inversion breakpoint. Moreover, this same interval was determined to be absent in all three patients with chromosomal deletions. These results suggest that this segment of DNA on chromosome 7q22.1 may contain specific gene(s) that have a significant role in myeloid malignancies.

Fine mapping of the human and mouse genes for the type I procollagen COOH-terminal proteinase enhancer protein

The human gene (PCOLCE) for the C-proteinase enhancer, a glycoprotein that enhances the enzymatic activity that cleaves the type I procollagen C-propeptide, was previously mapped to the same cytogenetic region (7q21.3-q22) as COL1A2, the type I collagen pro-alpha 2 chain gene. The apparent proximity of these two genes, whose products interact, might have reflected some mechanism for coregulation of expression. We have employed somatic cell hybrids, cosmid contigs, and interspecific backcross mice to investigate further the apparent proximity of the two genes. Our data show that PCOLCE and COL1A2 are separated by at least 6 Mb on human chromosome 7q and that Pcolce and Col1a2 are located on two separate chromosomes in mouse. These data also indicate that PCOLCE is located within a 10- to 15-cM region of conserved synteny between human chromosome 7 and mouse chromosome 5.

Lack of inhibition by dideoxy-forskolin and verapamil of DIDS-sensitive volume-activated Cl- secretion in human squamous lung carcinoma epithelial cells

The effect of osmotic stress on Cl- permeability in human squamous lung carcinoma epithelial (S1) cells was investigated using a macroscopic 125I efflux assay. Hypotonic challenge of monolayers led to a significant (P < 0.01) dose-related increase in efflux from pre-loaded cells, returning to pre-activation rates within 10 min. A similar magnitude of response could be produced by challenge with an isotonic low chloride-containing solution. Neither 100 mM dideoxy-forskolin nor 100 mM verapamil inhibited the increase in Cl- secretion after hypotonic challenge, whereas 100 mM DIDS inhibited volume-activated Cl- secretion by 55%. Both Northern and Western blot analysis confirmed the absence of MDR1 mRNA and P-glycoprotein in the S1 cells. We conclude that these cells have a volume-regulated Cl- secretory pathway that is independent of the ABC transporter, P-glycoprotein.

Skipping of multiple CFTR exons is not a result of single exon omissions

The omission of complete exons in a proportion of mature transcripts has been shown for a variety of genes. In the case of the cystic fibrosis transmembrane conductance regulator gene, this phenomenon has previously been observed for exons 4, 9 and 12. Here, we describe the detection of a combined skipping of exons 11 and 12 in the absence of detectable transcripts missing only exon 11. This constellation has been found both in peripheral blood cells and in specifically expressing lung tissue, and excludes the possibility that the simultaneous skipping of both exons is merely a stochastic combination of single exon skipping events.