Real time quantitative PCR

We have developed a novel "real time" quantitative PCR method. The method measures PCR product accumulation through a dual-labeled fluorogenic probe (i.e., TaqMan Probe). This method provides very accurate and reproducible quantitation of gene copies. Unlike other quantitative PCR methods, real-time PCR does not require post-PCR sample handling, preventing potential PCR product carry-over contamination and resulting in much faster and higher throughput assays. The real-time PCR method has a very large dynamic range of starting target molecule determination (at least five orders of magnitude). Real-time quantitative PCR is extremely accurate and less labor-intensive than current quantitative PCR methods.

Post-acute COVID-19 syndrome

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen responsible for the coronavirus disease 2019 (COVID-19) pandemic, which has resulted in global healthcare crises and strained health resources. As the population of patients recovering from COVID-19 grows, it is paramount to establish an understanding of the healthcare issues surrounding them. COVID-19 is now recognized as a multi-organ disease with a broad spectrum of manifestations. Similarly to post-acute viral syndromes described in survivors of other virulent coronavirus epidemics, there are increasing reports of persistent and prolonged effects after acute COVID-19. Patient advocacy groups, many members of which identify themselves as long haulers, have helped contribute to the recognition of post-acute COVID-19, a syndrome characterized by persistent symptoms and/or delayed or long-term complications beyond 4 weeks from the onset of symptoms. Here, we provide a comprehensive review of the current literature on post-acute COVID-19, its pathophysiology and its organ-specific sequelae. Finally, we discuss relevant considerations for the multidisciplinary care of COVID-19 survivors and propose a framework for the identification of those at high risk for post-acute COVID-19 and their coordinated management through dedicated COVID-19 clinics.

Identification and characterization of the familial adenomatous polyposis coli gene

DNA from 61 unrelated patients with adenomatous polyposis coli (APC) was examined for mutations in three genes (DP1, SRP19, and DP2.5) located within a 100 kb region deleted in two of the patients. The intron-exon boundary sequences were defined for each of these genes, and single-strand conformation polymorphism analysis of exons from DP2.5 identified four mutations specific to APC patients. Each of two aberrant alleles contained a base substitution changing an amino acid to a stop codon in the predicted peptide; the other mutations were small deletions leading to frameshifts. Analysis of DNA from parents of one of these patients showed that his 2 bp deletion is a new mutation; furthermore, the mutation was transmitted to two of his children. These data have established that DP2.5 is the APC gene.

Blastocyst score affects implantation and pregnancy outcome: towards a single blastocyst transfer

OBJECTIVE

To determine the relationship between blastocyst score and pregnancy outcome.

DESIGN

Retrospective review of blastocyst transfer in an IVF clinic.

SETTING

Private assisted reproductive technology unit.

PATIENT(S)

107 patients undergoing blastocyst culture and transfer of two embryos.

INTERVENTION(S)

Culture of all pronucleate embryos in sequential media to the blastocyst stage (day 5), followed by transfer of two blastocysts.

MAIN OUTCOME MEASURE(S)

Implantation rates, pregnancy rates, and twinning were analyzed.

RESULT(S)

When a patient received two top-scoring blastocysts (64% of patients), implantation and pregnancy rates were 70% and 87%, respectively. The twinning rate in this group was 61%. When only one top-quality blastocyst was available for transfer (21% of patients), the implantation and pregnancy rates were 50% and 70%. The twinning rate for this group was 50%. In contrast, when only low-scoring blastocysts were available for transfer (15% of patients), implantation and pregnancy rates were 28% and 44%, and the twinning rate was 29%. No monozygotic twins were observed in this group of patients.

CONCLUSION(S)

The ability to transfer one high-scoring blastocyst should lead to pregnancy rates greater than 60%, without the complication of twins.

Annual deaths attributable to obesity in the United States

CONTEXT

Obesity is a major health problem in the United States, but the number of obesity-attributable deaths has not been rigorously estimated.

OBJECTIVE

To estimate the number of deaths, annually, attributable to obesity among US adults.

DESIGN

Data from 5 prospective cohort studies (the Alameda Community Health Study, the Framingham Heart Study, the Tecumseh Community Health Study, the American Cancer Society Cancer Prevention Study I, and the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study) and 1 published study (the Nurses' Health Study) in conjunction with 1991 national statistics on body mass index distributions, population size, and overall deaths.

SUBJECTS

Adults, 18 years or older in 1991, classified by body mass index (kg/m2) as overweight (25-30), obese (30-35), and severely obese (>35).

MAIN OUTCOME MEASURE

Relative hazard ratio (HR) of death for obese or overweight persons.

RESULTS

The estimated number of annual deaths attributable to obesity varied with the cohort used to calculate the HRs, but findings were consistent overall. More than 80% of the estimated obesity-attributable deaths occurred among individuals with a body mass index of more than 30 kg/m2. When HRs were estimated for all eligible subjects from all 6 studies, the mean estimate of deaths attributable to obesity in the United States was 280184 (range, 236111-341153). Hazard ratios also were calculated from data for nonsmokers or never-smokers only. When these HRs were applied to the entire population (assuming the HR applied to all individuals), the mean estimate for obesity-attributable death was 324 940 (range, 262541-383410).

CONCLUSIONS

The estimated number of annual deaths attributable to obesity among US adults is approximately 280000 based on HRs from all subjects and 325000 based on HRs from only nonsmokers and never-smokers.

The effect of age on the association between body-mass index and mortality

BACKGROUND

The effect of age on optimal body weight is controversial, and few studies have had adequate numbers of subjects to analyze mortality as a function of body-mass index across age groups.

METHODS

We studied mortality over 12 years among white men and women who participated in the American Cancer Society's Cancer Prevention Study I (from 1960 through 1972). The 62,116 men and 262,019 women included in this analysis had never smoked cigarettes, had no history of heart disease, stroke, or cancer (other than skin cancer) at base line in 1959-1960, and had no history of recent unintentional weight loss. The date and cause of death for subjects who died were determined from death certificates. The associations between body-mass index (defined as the weight in kilograms divided by the square of the height in meters) and mortality were examined for six age groups in analyses in which we adjusted for age, educational level, physical activity, and alcohol consumption.

RESULTS

Greater body-mass index was associated with higher mortality from all causes and from cardiovascular disease in men and women up to 75 years of age. However, the relative risk associated with greater body-mass index declined with age. For example, for mortality from cardiovascular disease, the relative risk associated with an increment of 1 in the body-mass index was 1.10 (95 percent confidence interval, 1.04 to 1.16) for 30-to-44-year-old men and 1.03 (95 percent confidence interval, 1.02 to 1.05) for 65-to-74-year-old men. For women, the corresponding relative risk estimates were 1.08 (95 percent confidence interval, 1.05 to 1.11) and 1.02 (95 percent confidence interval, 1.02 to 1.03).

CONCLUSIONS

Excess body weight increases the risk of death from any cause and from cardiovascular disease in adults between 30 and 74 years of age. The relative risk associated with greater body weight is higher among younger subjects.

The neurofibromatosis type 1 gene encodes a protein related to GAP

cDNA walking and sequencing have extended the open reading frame for the neurofibromatosis type 1 gene (NF1). The new sequence now predicts 2485 amino acids of the NF1 peptide. A 360 residue region of the new peptide shows significant similarity to the known catalytic domains of both human and bovine GAP (GTPase activating protein). A much broader region, centered around this same 360 amino acid sequence, is strikingly similar to the yeast IRA1 product, which has a similar amino acid sequence and functional homology to mammalian GAP. This evidence suggests that NF1 encodes a cytoplasmic GAP-like protein that may be involved in the control of cell growth by interacting with proteins such as the RAS gene product. Mapping of the cDNA clones has confirmed that NF1 spans a t(1;17) translocation mutation and that three active genes lie within an intron of NF1, but in opposite orientation.

Deletions and a translocation interrupt a cloned gene at the neurofibromatosis type 1 locus

Three new neurofibromatosis type 1 (NF1) mutations have been detected and characterized. Pulsed-field gel and Southern blot analyses reveal the mutations to be deletions of 190, 40, and 11 kb of DNA. The 11 kb deletion does not contain any of the previously characterized genes that lie between two NF1 translocation breakpoints, but it does include a portion of a rodent/human conserved DNA sequence previously shown to span one of the translocation breakpoints. By screening cDNA libraries with the conserved sequence, we identified a number of cDNA clones from the translocation breakpoint region (TBR), one of which hybridizes to an approximately 11 kb mRNA. The TBR gene crosses at least one of the chromosome 17 translocation breakpoints found in NF1 patients. Furthermore, the newly characterized NF1 deletions remove internal exons of the TBR gene. Although these mutations might act by compromising regulatory elements affecting some other gene, these findings strongly suggest that the TBR gene is the NF1 gene.

A major segment of the neurofibromatosis type 1 gene: cDNA sequence, genomic structure, and point mutations

Overlapping cDNA clones from the translocation breakpoint region (TBR) gene, recently discovered at the neurofibromatosis type 1 locus and found to be interrupted by deletions and a t(17;22) translocation, have been sequenced. A 4 kb sequence of the transcript of the TBR gene has been compared with sequences of genomic DNA, identifying a number of small exons. Identification of splice junctions and a large open reading frame indicates that the gene is oriented with its 5' end toward the centromere, in opposition to the three known active genes in the region. PCR amplification of a subset of the exons, followed by electrophoresis of denatured product on native gels, identified six variant conformers specific to NF1 patients, indicating base pair changes in the gene. Sequencing revealed that one mutant allele contains a T----C transition changing a leucine to a proline; another NF1 allele harbors a C----T transition changing an arginine to a stop codon. These results establish the TBR gene as the NF1 gene and provide a description of a major segment of the gene.

Mutation incidence and coincidence in non small-cell lung cancer: meta-analyses by ethnicity and histology (mutMap)

BACKGROUND

Meta-analyses were conducted to characterize patterns of mutation incidence in non small-cell lung cancer (NSCLC).

DESIGN

Nine genes with the most complete published mutation coincidence data were evaluated. One meta-analysis generated a 'mutMap' to visually represent mutation coincidence by ethnicity (Western/Asian) and histology (adenocarcinoma [ADC] or squamous cell carcinoma). Another meta-analysis evaluated incidence of individual mutations. Extended analyses explored incidence of EGFR and KRAS mutations by ethnicity, histology, and smoking status.

RESULTS

Genes evaluated were TP53, EGFR, KRAS, LKB1, EML4-ALK, PTEN, BRAF, PIK3CA, and ErbB2. The mutMap highlighted mutation coincidences occurring in ≥5% of patients, including TP53 with KRAS or EGFR mutations in patients with ADC, and TP53 with LKB1 mutation in Western patients. TP53 was the most frequently mutated gene overall. Frequencies of TP53, EGFR, KRAS, LKB1, PTEN, and BRAF mutations were influenced by histology and/or ethnicity. Although EGFR mutations were most frequent in patients with ADC and never/light smokers from Asia, and KRAS mutations were most frequent in patients with ADC and ever/heavy smokers from Western countries, both were detected outside these subgroups.

CONCLUSIONS

Potential molecular pathology segments of NSCLC were identified. Further studies of mutations in NSCLC are warranted to facilitate more specific diagnoses and guide treatment.

Identification of deletion mutations and three new genes at the familial polyposis locus

Small (100-260 kb), nested deletions were characterized in DNA from two unrelated patients with familial adenomatous polyposis coli (APC). Three candidate genes located within the deleted region were ascertained and a previous candidate gene, MCC, was shown to be located outside the deleted region. One of the new genes contained sequence identical to SRP19, the gene coding for the 19 kd component of the ribosomal signal recognition particle. The second, provisionally designated DP1 (deleted in polyposis 1), was found to be transcribed in the same orientation as MCC. Two other cDNAs, DP2 and DP3, were found to overlap, forming a single gene, DP2.5, that is transcribed in the same orientation as SRP19.

A prospective randomized trial of blastocyst culture and transfer in in-vitro fertilization

The effectiveness of blastocyst culture and transfer in human in-vitro fertilization (IVF) was evaluated in a prospective randomized trial in patients having a moderate to good response to gonadotrophin stimulation. Embryos were transferred either on day 3 after culture to around the 8-cell stage in Ham's F-10 medium supplemented with fetal cord serum, or on day 5 after culture to the blastocyst stage in the sequential serum-free media G 1.2 and G 2.2. The pregnancy rates after transfer on day 3 or day 5 were equivalent, 66 and 71% respectively; however, significantly more embryos were transferred on day 3 (3.7) than on day 5 (2.2). The number of blastocysts transferred did not affect the implantation rate, and pregnancy rates when either two or three blastocysts were transferred were 68 and 87% respectively. The implantation rate of the blastocysts (50.5% fetal heart beat) was significantly higher compared to the cleavage stage embryos transferred on day 3 (30.1%). The percentage of blastocyst development was not affected by the number of 2-pronuclear embryos, or by maternal age. Irrespective of the number of blastocysts formed, pregnancy rates were similar. Furthermore, the pregnancy rate following blastocyst transfer in patients with 10 or more follicles at the time of human chorionic gonadotrophin administration was not affected by patient age. More than 60% of patients having blastocyst culture and transfer had supernumerary embryos for cryopreservation. The establishment of a pregnancy following thaw and transfer confirmed the viability of cryopreserved blastocysts cultured in the absence of serum or co-culture. The ability to transfer just two blastocysts while maintaining high pregnancy rates will therefore help to eliminate high order multiple gestations and improve the overall efficiency of human IVF.

The definition of weight maintenance

There is currently no consensus on the definition of weight maintenance in adults. Issues to consider in setting a standard definition include expert opinion, precedents set in previous studies, public health and clinical applications, comparability across body sizes, measurement error, normal weight fluctuations and biologic relevance. To be useful, this definition should indicate an amount of change less than is clinically relevant, but more than expected from measurement error or fluctuations in fluid balance under normal conditions. It is an advantage for the definition to be graded by body size and to be easily understood by the public as well as scientists. Taking all these factors into consideration, the authors recommend that long-term weight maintenance in adults be defined as a weight change of <3% of body weight.

Siah-1 mediates a novel beta-catenin degradation pathway linking p53 to the adenomatous polyposis coli protein

The adenomatous polyposis coli (APC) tumor-suppressor protein, together with Axin and GSK3beta, forms a Wnt-regulated signaling complex that mediates phosphorylation-dependent degradation of beta-catenin by the proteasome. Siah-1, the human homolog of Drosophila seven in absentia, is a p53-inducible mediator of cell cycle arrest, tumor suppression, and apoptosis. We have now found that Siah-1 interacts with the carboxyl terminus of APC and promotes degradation of beta-catenin in mammalian cells. The ability of Siah-1 to downregulate beta-catenin signaling was also demonstrated by hypodorsalization of Xenopus embryos. Unexpectedly, degradation of beta-catenin by Siah-1 was independent of GSK3beta-mediated phosphorylation and did not require the F box protein beta-TrCP. These results indicate that APC and Siah-1 mediate a novel beta-catenin degradation pathway linking p53 activation to cell cycle control.

Practice Parameter: Treatment of Parkinson disease with motor fluctuations and dyskinesia (an evidence-based review): [RETIRED]

Objective: To make evidence-based treatment recommendations for the medical and surgical treatment of patients with Parkinson disease (PD) with levodopa-induced motor fluctuations and dyskinesia. To that end, five questions were addressed. 1. Which medications reduce off time? 2. What is the relative efficacy of medications in reducing off time? 3. Which medications reduce dyskinesia? 4. Does deep brain stimulation (DBS) of the subthalamic nucleus (STN), globus pallidus interna (GPi), or ventral intermediate (VIM) nucleus of the thalamus reduce off time, dyskinesia, and antiparkinsonian medication usage and improve motor function? 5. Which factors predict improvement after DBS?

Methods: A 10-member committee including movement disorder specialists and general neurologists evaluated the available evidence based on a structured literature review including MEDLINE, EMBASE, and Ovid databases from 1965 through June 2004.

Results, Conclusions, and Recommendations: 1. Entacapone and rasagiline should be offered to reduce off time (Level A). Pergolide, pramipexole, ropinirole, and tolcapone should be considered to reduce off time (Level B). Apomorphine, cabergoline, and selegiline may be considered to reduce off time (Level C). 2. The available evidence does not establish superiority of one medicine over another in reducing off time (Level B). Sustained release carbidopa/levodopa and bromocriptine may be disregarded to reduce off time (Level C). 3. Amantadine may be considered to reduce dyskinesia (Level C). 4. Deep brain stimulation of the STN may be considered to improve motor function and reduce off time, dyskinesia, and medication usage (Level C). There is insufficient evidence to support or refute the efficacy of DBS of the GPi or VIM nucleus of the thalamus in reducing off time, dyskinesia, or medication usage, or to improve motor function. 5. Preoperative response to levodopa predicts better outcome after DBS of the STN (Level B).

Somatic mutations in the neurofibromatosis 1 gene in human tumors

The neurofibromatosis 1 (NF1) gene product, neurofibromin, contains a GTPase-activating protein (GAP)-related domain, or NF1 GRD, that is able to down-regulate p21ras by stimulating its intrinsic GTPase. Since p21ras.GTP is a major regulator of growth and differentiation, mutant neurofibromins resulting from somatic mutations in the NF1 gene might interfere with ras signaling pathways and contribute to the development of tumors. We describe an amino acid substitution in the NF1 GRD, altering Lys-1423, that has occurred in three tumor types: colon adenocarcinoma, myelodysplastic syndrome, and anaplastic astrocytoma, and in one family with neurofibromatosis 1. The GAP activity of the mutant NF1 GRD is 200- to 400-fold lower than that of wild type, whereas binding affinity is unaffected. Thus, germline mutations in NF1 that cause neurofibromatosis 1 can also occur in somatic cells and contribute to the development of sporadic tumors, including tumors not associated with neurofibromatosis 1.

Presentation and Outcomes of Patients with ESKD and COVID-19

BACKGROUND

The relative immunosuppression and high prevalence of comorbidities in patients with ESKD on dialysis raise concerns that they may have an elevated risk of severe coronavirus disease 2019 (COVID-19), but outcomes for COVID-19 in such patients are unclear.

METHODS

To examine presentation and outcomes of COVID-19 in patients with ESKD on dialysis, we retrospectively collected clinical data on 59 patients on dialysis who were hospitalized with COVID-19. We used Wilcoxon rank sum and Fischer exact tests to compare patients who died versus those still living.

RESULTS

Two of the study's 59 patients were on peritoneal dialysis, and 57 were on hemodialysis. Median age was 63 years, with high prevalence of hypertension (98%) and diabetes (69%). Patients who died were significantly older than those still living (median age, 75 versus 62 years) and had a higher median Charlson comorbidity index (8 versus 7). The most common presenting symptoms were fever (49%) and cough (39%); initial radiographs most commonly showed multifocal or bilateral opacities (59%). By end of follow-up, 18 patients (31%) died a median 6 days after hospitalization, including 75% of patients who required mechanical ventilation. Eleven of those who died had advanced directives against intubation. The remaining 41 patients (69%) were discharged home a median 8 days after admission. The median initial white blood cell count was significantly higher in patients who died compared with those still living (7.5 versus 5.7×103/μl), as was C-reactive protein (163 versus 80 mg/L).

CONCLUSIONS

The association of COVID-19 with high mortality in patients with ESKD on dialysis reinforces the need to take appropriate infection control measures to prevent COVID-19 spread in this vulnerable population.

Accuracy of current, 4-year, and 28-year self-reported body weight in an elderly population

Participants in the 1987-1989 recall of the Charleston Heart Study were asked to report their current weight and to recall their weight in 1984 and 1960. Reported weights were compared with weights measured in the respective time periods. Subjects included male and female blacks and whites between ages 62 and 100 years. Correlations between reported and measured weights over all subjects were 0.979 for current, 0.935 for 4-year, and 0.822 for 28-year recall. Subjects in the lowest body mass index quartile overestimated their weight, while subjects in the highest quartile underestimated their weight. This tendency increased as the elapsed time increased. Deviations between measured and reported weights increased as performance on cognitive tests declined.

Associations between gender, age and waist circumference

In December 2008, the World Health Organization (WHO) convened a consultation to discuss cut-points for waist circumference (WC). As part of that effort, this paper examines the impact of gender and age on WC. As WC is influenced by body weight, body composition and fat distribution, their associations with gender and age were reviewed. We also noted the relationships with sex hormones, parity and menopause. We then summarized data on gender, age and WC. This presentation is not intended to be comprehensive, but to provide an overview of the available research. There are large differences in body composition in men and women, with women having more body fat. Fat distribution also differs with gender, with men having a relatively more central distribution of fat. These differences begin early in life and become more apparent in puberty due to changes in sex hormone levels. In both, men and women, waist and waist-to-hip ratio increase with age. A large portion of this increase is driven by gains in body weight, but the increases observed are larger than those that would be predicted from increases in the body mass index alone, and increases in WC are seen with aging in the absence of weight gain. The current practice of using seperate waist cut-points by gender is appropriate. Although WC increases with age, so does the risk of many chronic diseases. An evaluation of the need for age-specific waist cut-points in adults would need to consider disease risk.

Noninvasive assessment of human embryo nutrient consumption as a measure of developmental potential

OBJECTIVE

To determine the relationship between blastocyst development and morphology and embryo metabolism.

DESIGN

Noninvasive assessment of carbohydrate uptake and ammonium production by individual embryos.

SETTING

Private assisted reproductive technology unit.

PATIENT(S)

Patients donated, with consent, cryopreserved pronucleate embryos and noncryopreserved blastocysts.

INTERVENTION(S)

Culture of 60 thawed pronucleate embryos in sequential media to the blastocyst stage with concomitant noninvasive analysis of embryo metabolism and analysis of 13 blastocysts from noncryopreserved embryos.

MAIN OUTCOME MEASURE(S)

Pyruvate and glucose consumption as well as blastocyst formation and quality.

RESULT(S)

Pyruvate and glucose uptakes on day 4 were significantly higher by embryos that went on to form blastocysts than by embryos that failed to develop to the blastocyst stage. Glucose uptakes were greatest in those blastocysts of highest grade, whereas pyruvate uptakes were similar irrespective of blastocyst grade, indicating that glucose is the more important nutrient for the human blastocyst. Among blastocysts of the same grade from the same patient, there was considerable spread of glucose consumption, indicating that glucose consumption may be of use in identifying blastocysts for transfer. Ammonium production by individual embryos was also measured, reflecting amino acid transamination and use by the human embryo.

CONCLUSION(S)

The ability to identify in culture the embryo with the highest developmental potential will facilitate the move to single-embryo transfers.

A prospective study of coronary heart disease in relation to fasting insulin, glucose, and diabetes. The Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVE

To determine the association of coronary heart disease (CHD) incidence with diabetes, fasting serum glucose, and insulin in a biracial cohort of middle-aged men and women.

RESEARCH DESIGN AND METHODS

We examined a population-based sample (n = 13,446 free of baseline CHD) from four U.S. communities in 1987-1989. We defined diabetes on the basis of baseline fasting glucose concentration (> or = 7.8 mmol/l), medical history, and current medications. A central laboratory measured fasting insulin with a nonspecific radioimmunoassay. After 4-7 years, 209 men and 96 women developed CHD.

RESULTS

After adjustment for sociodemographic characteristics, smoking status, ethanol intake, sports participation, and hormone replacement therapy, the relative risk of CHD for people with diabetes versus those without diabetes was 3.45 (95% CI 2.16-5.50) among women and 2.52 (1.78-3.56) among men. Relative risks of CHD with diabetes were somewhat lower in blacks than non-blacks, but because diabetes was more than twice as prevalent in blacks, the percentage of CHD cases attributable to diabetes (population attributable risk) was 27% for black women, 15% for non-black women, 8% for black men, and 12% for non-black men. Among people without diabetes, fasting glucose was not independently associated with CHD incidence. Among women without diabetes, there was a positive association between fasting insulin and CHD; multivariable adjusted relative risks of CHD across quintiles of fasting insulin were 1.00, 0.76, 2.08, 2.08 and 2.82 (P for linear trend = 0.02). However, among men without diabetes, fasting insulin and CHD were not associated.

CONCLUSIONS

Diabetes conveys a high risk of CHD in black and non-black middle-aged men and women. Fasting insulin, however, is a CHD risk factor only among women in this cohort.

Verapamil suppresses atherosclerosis in cholesterol-fed rabbits

The effect of verapamil, a drug that reduces the concentration of intracellular calcium, on atherogenesis was evaluated in rabbits fed a cholesterol-rich diet for 10 weeks. Ten rabbits received oral verapamil, 8 mg/kg daily; eight received the same oral dose and 0.5 mg/kg daily subcutaneously; nine received oral lanthanum, 35 mg/kg daily, and nine were controls. Over the 10 week period, all groups had average serum cholesterol levels greater than 1,500 mg/dl (normal = 90 +/- 63 mg/dl). At the end of the experiment, the aortas were removed, opened and stained for lipid with Sudan IV. The extent of atherosclerosis was determined by planimetry. The group receiving oral and parenteral verapamil had significantly less atherosclerosis (25 +/- 26% of total intimal area; mean +/- standard deviation), as compared with the controls (73 +/- 24%). Reduction of atherosclerosis with oral verapamil (51 +/- 22%) and lanthanum (59 +/- 31) was not statistically significant. Indexes of contractility in isolated right ventricular papillary muscles (developed tension at maximal length [Lmax] and maximal velocity of shortening [Vmax]) were reduced in the group treated with oral and parenteral verapamil, but not in the others. It is concluded that verapamil suppresses the development of atherosclerosis in rabbits fed a cholesterol-rich diet.

Outcomes for Patients With COVID-19 and Acute Kidney Injury: A Systematic Review and Meta-Analysis

INTRODUCTION

There are limited data on the association of kidney dysfunction with prognosis in coronavirus disease 2019 (COVID-19), and the extent to which acute kidney injury (AKI) predisposes patients to severe illness and inferior outcomes is unclear. We aim to assess the incidence of AKI among patients with COVID-19 and examine their associations with patient outcomes as reported in the available literature thus far.

METHODS

We systematically searched MEDLINE, EMBASE, SCOPUS, and MedRxiv databases for full-text articles available in English published from December 1, 2019 to May 24, 2020. Clinical information was extracted and examined from 20 cohorts that met inclusion criteria, covering 13,137 mostly hospitalized patients confirmed to have COVID-19. Two authors independently extracted study characteristics, results, outcomes, study-level risk of bias, and strength of evidence across studies. Neither reviewer was blind to journal titles, study authors, or institutions.

RESULTS

Median age was 56 years, with 55% male patients. Approximately 43% of patients had severe COVID-19 infection, and approximately 11% died. Prevalence of AKI was 17%; 77% of patients with AKI experienced severe COVID-19 infection, and 52% died. AKI was associated with increased odds of death among COVID-19 patients (pooled odds ratio, 15.27; 95% CI 4.82-48.36), although there was considerable heterogeneity across studies and among different regions in the world. Approximately 5% of all patients required use of renal replacement therapy (RRT).

CONCLUSIONS

Kidney dysfunction is common among patients with COVID-19, and patients who develop AKI have inferior outcomes. Additional research into management and potential mechanisms of this association is needed.

Genomic organization of the neurofibromatosis 1 gene (NF1)

Neurofibromatosis 1 maps to chromosome band 17q11.2, and the NF1 locus has been partially characterized. Even though the full-length NF1 cDNA has been sequenced, the complete genomic structure of the NF1 gene has not been elucidated. The 5' end of NF1 is embedded in a CpG island containing a NotI restriction site, and the remainder of the gene lies in the adjacent 350-kb NotI fragment. In our efforts to develop a comprehensive screen for NF1 mutations, we have isolated genomic DNA clones that together harbor the entire NF1 cDNA sequence. We have identified all intron-exon boundaries of the coding region and established that it is composed of 59 exons. Furthermore, we have defined the 3'-untranslated region (3'-UTR) of the NF1 gene; it spans approximately 3.5 kb of genomic DNA sequence and is continuous with the stop codon. Oligonucleotide primer pairs synthesized from exon-flanking DNA sequences were used in the polymerase chain reaction with cloned, chromosome 17-specific genomic DNA as template to amplify NF1 exons 1 through 27b and the exon containing the 3'-UTR separately. This information should be useful for implementing a comprehensive NF1 mutation screen using genomic DNA as template.