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IMPORTANCE: Hypertension poses a substantial public health challenge. Despite clinical practice guidelines for hypertension management, clinician adherence to these guidelines remains suboptimal. OBJECTIVE: To develop a taxonomy of suboptimal adherence scenarios for severe hypertension and identify barriers to guideline adherence. DESIGN, SETTING, and PARTICIPANTS: This qualitative content analysis using electronic health records (EHRs) of Yale New Haven Health System included participants who had at least 2 consecutive visits with markedly elevated blood pressure (BP; defined as at least 2 consecutive readings of systolic BP ≥160 mm Hg and diastolic BP ≥100 mm Hg) between January 1, 2013, and December 31, 2021, and no prescription for antihypertensive medication within a 90 days of the second BP measurement. Data analysis was conducted from January to December 2023. MAIN OUTCOMES AND MEASURES: The primary outcome was scenarios and influencing factors contributing to clinician nonadherence to the guidelines for hypertension management. A thematic analysis of EHR data was conducted to generate a pragmatic taxonomy of scenarios of suboptimal clinician guideline adherence in the management of severe hypertension. RESULTS: Of the 20â¯654 patients who met criteria, 200 were randomly selected and thematic saturation was reached after analyzing 100 patients (mean [SD] age at index visit, 66.5 [12.8] years; 50 female [50%]; 8 Black [8%]; 5 Hispanic or Latino [5%]; 85 White [85%]). Three content domains emerged: (1) clinician-related scenarios (defined as noninitiation or nonintensification of treatment due to issues relating to clinician intention, capability, or scope), which included 2 subcategories (did not address and diffusion of responsibility); (2) patient-related scenarios (defined as noninitiation or nonintensification of treatment due to patient behavioral considerations), which included 2 subcategories (patient nonadherence and patient preference); and (3) clinical complexity-related scenarios (defined as noninitiation or nonintensification of treatment due to clinical situational complexities), which included 3 subcategories (diagnostic uncertainty, maintenance of current intervention, and competing medical priorities). CONCLUSIONS AND RELEVANCE: In this qualitative study of EHR data, a taxonomy of suboptimal adherence scenarios for severe hypertension was developed and barriers to guideline adherence were identified. This pragmatic taxonomy lays the foundation for developing targeted interventions to improve clinician adherence to guidelines and patient outcomes.
Subject(s)
Guideline Adherence , Hypertension , Qualitative Research , Humans , Hypertension/drug therapy , Female , Guideline Adherence/statistics & numerical data , Male , Middle Aged , Aged , Electronic Health Records/statistics & numerical data , Antihypertensive Agents/therapeutic use , Practice Guidelines as Topic , AdultABSTRACT
IMPORTANCE: Hypertension poses a significant public health challenge. Despite clinical practice guidelines for hypertension management, clinician adherence to these guidelines remains suboptimal. OBJECTIVE: This study aims to develop a taxonomy of suboptimal adherence scenarios for severe hypertension and identify barriers to guideline adherence. DESIGN: We conducted a qualitative content analysis using electronic health records (EHRs) of Yale New Haven Health System who had at least two consecutive visits between January 1, 2013, and October 31, 2018. SETTING: This was a thematic analysis of EHR data to generate a real-world taxonomy of scenarios of suboptimal clinician guideline adherence in the management of severe hypertension. PARTICIPANTS: We identified patients with markedly elevated blood pressure ([BP]; defined as at least 2 consecutive readings of BP ≥160/100 mmHg) and no prescription for antihypertensive medication within a 90-day of the 2nd BP elevation (n=4,828). We randomly selected 100 records from the group of all eligible patients for qualitative analysis. MAIN OUTCOMES AND MEASURES: The scenarios and influencing factors contributing to clinician non-adherence to the guidelines for hypertension management. RESULTS: Thematic saturation was reached after analyzing 100 patient records. Three content domains emerged: clinician-related scenarios (neglect and diffusion of responsibility), patient-related scenarios (patient non-adherence and patient preference), and clinical complexity-related scenarios (diagnostic uncertainty, maintenance of current intervention and competing medical priorities). Through a metareview of literature, we identified several plausible influencing factors, including a lack of protocols and processes that clearly define the roles within the institution to implement guidelines, infrastructure limitations, and clinicians' lack of autonomy and authority, excessive workload, time constraints, clinician belief that intervention was not part of their role, or perception that guidelines restrict clinical judgment. CONCLUSIONS AND RELEVANCE: This study illuminates reasons for suboptimal adherence to guidelines for managing markedly elevated BP. The taxonomy of suboptimal adherence scenarios, derived from real-world EHR data, is pragmatic and provides a basis for developing targeted interventions to improve clinician guideline adherence and patient outcomes.
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We report a rare case with gabapentin overdose that caused severe rhabdomyolysis and acute tubular necrosis which required renal replacement therapy. A better awareness of its adverse effect and a close follow-up of laboratory tests are recommended. Prescribers should also be aware of high-risk population and monitor for signs of abuse.
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BACKGROUND: Telbivudine can cause severe side effects, including myositis, neuritis, rhabdomyolysis, and lactic acidosis. However, reported cases of telbivudine leading to multiple organ failure are rare. Here, we report a case of telbivudine-induced severe polymyositis, lactic acidosis, and multiple organ failure. CASE PRESENTATION: A 30-year-old Chinese man with hepatitis B virus infection received antiviral treatment with 600 mg of telbivudine daily for more than 11 months. He developed progressive weakness and myalgia, and subsequently experienced palpitations, chest tightness, lethargy, hypotension, and hypoxemia. Blood tests showed markedly elevated levels of alanine aminotransferase (955 U/L), aspartate aminotransferase (1375 U/L), blood urea nitrogen (14.9 mmol/L), creatine kinase (peak at 8050 U/L), and blood lactate (>20.0 mmol/L). His symptoms improved after continuous renal replacement therapy and short-term methylprednisolone treatment. Hyperbaric oxygen therapy, physical therapy, and rehabilitation for more than 2 months led to recovery of muscle strength to the normal range. CONCLUSIONS: We conclude that continuous renal replacement and steroid therapies play key roles in stabilizing telbivudine-induced severe rhabdomyolysis, lactic acidosis, and multiple organ failure. Hyperbaric oxygen, physical therapy, and rehabilitation may aid in functional recovery after the acute phase of lactic acidosis and organ failure.
Subject(s)
Acidosis, Lactic/chemically induced , Antiviral Agents/adverse effects , Hepatitis B, Chronic/drug therapy , Multiple Organ Failure/chemically induced , Renal Replacement Therapy , Rhabdomyolysis/chemically induced , Thymidine/analogs & derivatives , Acidosis, Lactic/therapy , Adult , Antiviral Agents/administration & dosage , Asian People , Humans , Male , Multiple Organ Failure/therapy , Physical Therapy Modalities , Rhabdomyolysis/therapy , Telbivudine , Thymidine/administration & dosage , Thymidine/adverse effects , Treatment OutcomeABSTRACT
BACKGROUND: Although multiple approaches have been used to create biological pacemakers in animal models, induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) have not been investigated for this purpose. We now report pacemaker function of iPSC-CMs in a canine model. METHODS AND RESULTS: Embryoid bodies were derived from human keratinocytes, their action potential characteristics determined, and their gene expression profiles and markers of differentiation identified. Atrioventricular blocked dogs were immunosuppressed, instrumented with VVI pacemakers, and injected subepicardially into the anterobasal left ventricle with 40 to 75 rhythmically contracting embryoid bodies (totaling 1.3-2×106 cells). ECG and 24-hour Holter monitoring were performed biweekly. After 4 to 13 weeks, epinephrine (1 µg kg-1 min-1) was infused, and the heart removed for histological or electrophysiological study. iPSC-CMs largely lost the markers of pluripotency, became positive for cardiac-specific markers. and manifested If-dependent automaticity. Epicardial pacing of the injection site identified matching beats arising from that site by week 1 after implantation. By week 4, 20% of beats were electronically paced, 60% to 80% of beats were matching, and mean and maximal biological pacemaker rates were 45 and 75 beats per minute. Maximum night and day rates of matching beats were 53±6.9 and 69±10.4 beats per minute, respectively, at 4 weeks. Epinephrine increased rate of matching beats from 35±4.3 to 65±4.0 beats per minute. Incubation of embryoid bodies with the vital dye, Dil, revealed the persistence of injected cells at the site of administration. CONCLUSIONS: iPSC-CMs can integrate into host myocardium and create a biological pacemaker. Although this is a promising development, rate and rhythm of the iPSC-CMs pacemakers remain to be optimized.
Subject(s)
Atrioventricular Block/surgery , Biological Clocks , Cell Differentiation , Heart Rate , Induced Pluripotent Stem Cells/transplantation , Myocytes, Cardiac/transplantation , Stem Cell Transplantation , Action Potentials , Animals , Atrioventricular Block/metabolism , Atrioventricular Block/physiopathology , Cardiac Pacing, Artificial , Cell Line , Disease Models, Animal , Dogs , Electrocardiography , Electrophysiologic Techniques, Cardiac , Gene Expression Profiling/methods , Humans , Induced Pluripotent Stem Cells/metabolism , Kruppel-Like Factor 4 , Kruppel-Like Transcription Factors/genetics , Kruppel-Like Transcription Factors/metabolism , Myocytes, Cardiac/metabolism , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , Oligonucleotide Array Sequence Analysis , Phenotype , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Recovery of Function , SOXB1 Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , Time Factors , Transcriptome , TransfectionABSTRACT
Present: Due to an error made by the authors while submitting a revision, Dr. Tuan Zea Tan was omitted from the list of authors.Corrected: Correct author list can be found below. Authors sincerely apologize for this oversight. Ila Datar1, Xiaoliang Qiu1, Hong Zhi Ma1, Miranda Yeung1, Shweta Aras1, Ivana de la Serna1, Fahd Al-Mulla2, Tuan Zea Tan3, Jean Paul Thiery3, Robert Trumbly1, Xuan Fan4, Hongjuan Cui4 and Kam C. Yeung1 1 Department of Biochemistry and Cancer Biology, University of Toledo, College of Medicine, Health Science Campus, Toledo, OH, USA 2 Kuwait University, Faculty of Medicine. P.O. Box 24923, Safat, Kuwait 3 Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 4 State Key Laboratory Of Silkworm Genome Biology, Chongqing, China Original article: Oncotarget. 2015; 6(36): 39050-61. doi: 10.18632/oncotarget.5176.
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BACKGROUND: Drugs are screened for delayed rectifier potassium current (IKr) blockade to predict long QT syndrome prolongation and arrhythmogenesis. However, single-cell studies have shown that chronic (hours) exposure to some IKr blockers (eg, dofetilide) prolongs repolarization additionally by increasing late sodium current (INa-L) via inhibition of phosphoinositide 3-kinase. We hypothesized that chronic dofetilide administration to intact dogs prolongs repolarization by blocking IKr and increasing INa-L. METHODS AND RESULTS: We continuously infused dofetilide (6-9 µg/kg bolus+6-9 µg/kg per hour IV infusion) into anesthetized dogs for 7 hours, maintaining plasma levels within the therapeutic range. In separate experiments, myocardial biopsies were taken before and during 6-hour intravenous dofetide infusion, and the level of phospho-Akt was determined. Acute and chronic dofetilide effects on action potential duration (APD) were studied in canine left ventricular subendocardial slabs using microelectrode techniques. Dofetilide monotonically increased QTc and APD throughout 6.5-hour exposure. Dofetilide infusion during ≥210 minutes inhibited Akt phosphorylation. INa-L block with lidocaine shortened QTc and APD more at 6.5 hours than at 50 minutes (QTc) or 30 minutes (APD) dofetilide administration. In comparison, moxifloxacin, an IKr blocker with no effects on phosphoinositide 3-kinase and INa-L prolonged APD acutely but no additional prolongation occurred on chronic superfusion. Lidocaine shortened APD equally during acute and chronic moxifloxacin superfusion. CONCLUSIONS: Increased INa-L contributes to chronic dofetilide effects in vivo. These data emphasize the need to include time and INa-L in evaluating the phosphoinositide 3-kinase inhibition-derived proarrhythmic potential of drugs and provide a mechanism for benefit from lidocaine administration in clinical acquired long QT syndrome.
Subject(s)
Electrophysiological Phenomena/drug effects , Heart Ventricles/metabolism , Long QT Syndrome/drug therapy , Phenethylamines/administration & dosage , Sodium/metabolism , Sulfonamides/administration & dosage , Animals , Disease Models, Animal , Dogs , Dose-Response Relationship, Drug , Heart Ventricles/drug effects , Infusions, Intravenous , Long QT Syndrome/metabolism , Long QT Syndrome/physiopathology , Male , Patch-Clamp Techniques , Phenethylamines/pharmacokinetics , Potassium Channel Blockers/administration & dosage , Potassium Channel Blockers/pharmacokinetics , Sulfonamides/pharmacokineticsABSTRACT
OBJECTIVES: Genetic testing, a gold standard for long QT syndrome (LQTS) diagnosis, is time-consuming and costly when all the 15 candidate genes are screened. Since genotype-specific ECG patterns are present in most LQT1-3 mutation carriers, we tested the utility of ECG-guided genotyping in a large cohort of Chinese LQTS patients. METHODS AND RESULTS: We enrolled 230 patients (26 ± 17 years, 66% female) with a clinical diagnosis of LQTS. Genotypes were predicted as LQT1-3 based on the presence of ECG patterns typical for each genotype in 200 patients (85 LQT1, 110 LQT2 and 5 LQT3). Family-based genotype prediction was also conducted if gene-specific ECG patterns were found in other affected family members. Mutational screening identified 104 mutations (44% novel), i.e. 46 KCNQ1, 54 KCNH2 and 4 SCN5A mutations. The overall predictive accuracy of ECG-guided genotyping was 79% (157/200) and 79% (67/85), 78% (86/110) and 80% (4/5) for LQT1, LQT2 and LQT3, respectively. The predictive accuracy was 98% (42/43) when family-based ECG assessment was performed. CONCLUSIONS: From this large-scale genotyping study, we found that LQT2 is the most common genotype among the Chinese. Family-based ECG-guided genotyping is highly accurate. ECG-guided genotyping is time- and cost-effective. We therefore recommend it as an optimal approach for the genetic diagnosis of LQTS.
Subject(s)
Genotype , KCNQ1 Potassium Channel/genetics , Long QT Syndrome/genetics , Adolescent , Adult , Asian People/genetics , China , Cohort Studies , Electrocardiography , Female , Gene Frequency , Genetic Testing/methods , Humans , Long QT Syndrome/diagnosis , Male , Middle Aged , Mutation , Phenotype , Polymerase Chain Reaction , Registries , Young AdultABSTRACT
Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of- function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment.
Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Chemokine CCL5/biosynthesis , Macrophages/pathology , Phosphatidylethanolamine Binding Protein/metabolism , Animals , Breast Neoplasms/blood supply , Breast Neoplasms/genetics , Cell Line, Tumor , Chemokine CCL5/genetics , Chemokine CCL5/metabolism , Female , Heterografts , Humans , Mice , Mice, Inbred BALB C , Neoplasm Invasiveness , Neoplasm Metastasis , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Phosphatidylethanolamine Binding Protein/genetics , Tumor MicroenvironmentABSTRACT
Raf Kinase Inhibitory Protein or RKIP was initially identified as a Raf-1 binding protein using the yeast 2-hybrid screen. RKIP inhibits the activation phosphorylation of MEK by Raf-1 by competitively inhibiting the binding of MEK to Raf-1 and thus exerting an inhibitory effect on the Raf-MEK-Erk pathway. RKIP has been identified as a metastasis suppressor gene. Expression of RKIP is low in cancer metastases. Although primary tumor growth remains unaffected, re- expression of RKIP inhibits cancer metastasis. Mechanistically, RKIP constrains metastasis by inhibiting angiogenesis, local invasion, intravasation, and colonization. The molecular mechanism of how RKIP inhibits these individual steps remains undefined. In our present study, using an unbiased PCR based screening and by analyzing DNA microarray expression datasets we observe that the expression of multiple metalloproteases (MMPs) including MMP1, MMP3, MMP10 and MMP13 are negatively correlated with RKIP expression in breast cancer cell lines and clinical samples. Since expression of MMPs by cancer cells is important for cancer metastasis, we hypothesize that RKIP may mediate suppression of breast cancer metastasis by inhibiting multiple MMPs. We show that the expression signature of RKIP and MMPs is better at predicting high metastatic risk than the individual gene. Using a combination of loss- and gain-of-function approaches, we find that MMP13 is the cause of RKIP-mediated inhibition of local cancer invasion. Interestingly expression of MMP13 alone is not sufficient to reverse the inhibition of breast cancer cell metastasis to the lung due to the expression of RKIP. We find that RKIP negatively regulates MMP13 through the Erk2 signaling pathway and the repression of MMP13 by RKIP is transcription factor AP-1 independent. Together, our findings indicate that RKIP inhibits cancer cell invasion, in part, via MMP13 inhibition. These data also implicate RKIP in the regulation of MMP transcription, suggesting a potential mechanism by which RKIP inhibits tumor progression and metastasis.
Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Matrix Metalloproteinase 13/genetics , Phosphatidylethanolamine Binding Protein/metabolism , Transcriptional Activation , Animals , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Transformation, Neoplastic , Disease-Free Survival , Gene Expression Regulation, Neoplastic , Humans , Mice , Mitogen-Activated Protein Kinase 1/metabolism , Neoplasm Invasiveness , Neoplasm Metastasis , Signal TransductionABSTRACT
Reproduction requires adequate energy stores for parents and offspring to survive. Kiss1 neurons, which are essential for fertility, have the potential to serve as the central sensors of metabolic factors that signal to the reproductive axis the presence of stored calories. Paradoxically, obesity is often accompanied by infertility. Despite excess circulating levels of insulin and leptin, obese individuals exhibit resistance to both metabolic factors in many neuron types. Thus, resistance to insulin or leptin in Kiss1 neurons could lead to infertility. Single deletion of the receptors for either insulin or the adipokine leptin from Kiss1 neurons does not impair adult reproductive dysfunction. However, insulin and leptin signaling pathways may interact in such a way as to obscure their individual functions. We hypothesized that in the presence of genetic or obesity-induced concurrent insulin and leptin resistance, Kiss1 neurons would be unable to maintain reproductive function. We therefore induced a chronic hyperinsulinemic and hyperleptinemic state in mice lacking insulin receptors in Kiss1 neurons through high fat feeding and examined the impact on fertility. In an additional, genetic model, we ablated both leptin and insulin signaling in Kiss1 neurons (IR/LepRKiss mice). Counter to our hypothesis, we found that the addition of leptin insensitivity did not alter the reproductive phenotype of IRKiss mice. We also found that weight gain, body composition, glucose and insulin tolerance were normal in mice of both genders. Nonetheless, leptin and insulin receptor deletion altered pubertal timing as well as LH and FSH levels in mid-puberty in a reciprocal manner. Our results confirm that Kiss1 neurons do not directly mediate the critical role that insulin and leptin play in reproduction. However, during puberty kisspeptin neurons may experience a critical window of susceptibility to the influence of metabolic factors that can modify the onset of fertility.
Subject(s)
Insulin/metabolism , Kisspeptins/metabolism , Leptin/metabolism , Neurons/metabolism , Puberty/metabolism , Signal Transduction , Animals , Female , Fertility , Kisspeptins/genetics , Male , Mice , Receptor, Insulin/genetics , Receptor, Insulin/metabolism , Receptors, Leptin/genetics , Receptors, Leptin/metabolism , Sexual MaturationABSTRACT
OBJECTIVE: The purpose of this study was to screen genetic variations in plakophilin-2 (PKP2) gene in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) and investigate the differences in clinical features between mutation and no-mutation groups. METHODS: Thirty unrelated Chinese patients clinically diagnosed with ARVC/D and 50 healthy controls were included. Genomic DNA was isolated from peripheral blood samples. PCR and direct sequencing were used to detect variations in PKP2 gene. RESULTS: Eight PKP2 mutant variants were identified in 10 ARVC/D patients (8 men, 2 women). Among the eight mutation, three (c.2194C>T, c. 1170+ 1G>A and c. 810_813delGGTC) were novel mutation. Clinical features of the PKP2 mutation group were similar to those of the non-mutation group. CONCLUSIONS: The rate of PKP2 mutation is 33.3% (10/30) in ARVC/D patients. The penetrance of PKP2 mutation for ARVC/D tends to be higher in man patients. No significant differences could be detected in phenotype characteristics between patients with and without PKP2 mutation.
Subject(s)
Arrhythmogenic Right Ventricular Dysplasia/genetics , Asian People/genetics , Plakophilins/genetics , Arrhythmogenic Right Ventricular Dysplasia/diagnosis , Female , Genetic Predisposition to Disease/genetics , Humans , Male , Mutation , PhenotypeABSTRACT
Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of reproductive age women. The syndrome is caused by a combination of environmental influences and genetic predisposition. Despite extensive efforts, the heritable factors contributing to PCOS development are not fully understood. The objective of this study was to test the hypothesis that genetic background contributes to the development of a PCOS-like reproductive and metabolic phenotype in mice exposed to excess DHEA during the pubertal transition. We tested whether the PCOS phenotype would be more pronounced on the diabetes-prone C57BL/6 background than the previously used strain, BALB/cByJ. In addition, we examined strain-dependent upregulation of the expression of ovarian and extra-ovarian candidate genes implicated in human PCOS, genes containing known strain variants, and genes involved with steroidogenesis or insulin sensitivity. These studies show that there are significant strain-related differences in metabolic response to excess androgen exposure during puberty. Additionally, our results suggest the C57BL/6J strain provides a more robust and uniform experimental platform for PCOS research than the BALB/cByJ strain.
Subject(s)
Androgens/metabolism , Animals , Blotting, Western , Estrous Cycle/physiology , Female , Humans , Insulin Resistance/physiology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Ovary/metabolism , Polycystic Ovary Syndrome/metabolismABSTRACT
Pubertal onset only occurs in a favorable, anabolic hormonal environment. The neuropeptide kisspeptin, encoded by the Kiss1 gene, modifies GnRH neuronal activity to initiate puberty and maintain fertility, but the factors that regulate Kiss1 neurons and permit pubertal maturation remain to be clarified. The anabolic factor insulin may signal nutritional status to these neurons. To determine whether insulin sensing plays an important role in Kiss1 neuron function, we generated mice lacking insulin receptors in Kiss1 neurons (IR(ΔKiss) mice). IR(ΔKiss) females showed a delay in vaginal opening and in first estrus, whereas IR(ΔKiss) males also exhibited late sexual maturation. Correspondingly, LH levels in IR(ΔKiss) mice were reduced in early puberty in both sexes. Adult reproductive capacity, body weight, fat composition, food intake, and glucose regulation were comparable between the 2 groups. These data suggest that impaired insulin sensing by Kiss1 neurons delays the initiation of puberty but does not affect adult fertility. These studies provide insight into the mechanisms regulating pubertal timing in anabolic states.
Subject(s)
Fertility/physiology , Kisspeptins/physiology , Puberty, Delayed/physiopathology , Receptor, Insulin/physiology , Animals , Estradiol/analogs & derivatives , Estradiol/pharmacology , Feedback, Physiological , Female , Fertility/genetics , Gonadotropin-Releasing Hormone/physiology , Insulin/physiology , Kisspeptins/deficiency , Kisspeptins/genetics , Luteinizing Hormone/physiology , Male , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Neurons/physiology , Puberty, Delayed/genetics , Receptor, Insulin/deficiency , Receptor, Insulin/genetics , Sexual Maturation/genetics , Sexual Maturation/physiologyABSTRACT
We report a case of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) which illustrates the natural progression of disease in the absence of availability of an implanted cardiac defibrillator (ICD). Electrocardiograms and cardiac imaging show the progress of ARVC and these clinical milestones of disease are presented herein.
ABSTRACT
BACKGROUND: Long QT syndrome (LQTS) is characterized by QT prolongation, syncope and sudden death. This study aims to explore the causes, clinical manifestations and therapeutic outcomes of Jervell and Lange-Nielsen syndrome (JLNS), a rare form of LQTS with congenital sensorineural deafness, in Chinese individuals. MATERIALS AND METHODS: Three JLNS kindreds from the Chinese National LQTS Registry were investigated. Mutational screening of KCNQ1 and KCNE1 genes was performed by polymerase chain reaction and direct DNA sequence analysis. LQTS phenotype and therapeutic outcomes were evaluated for all probands and family members. RESULTS: We identified 7 KCNQ1 mutations. c.1032_1117dup (p.Ser373TrpfsX10) and c.1319delT (p.Val440AlafsX26) were novel, causing JLNS in a 16-year-old boy with a QTc (QT interval corrected for heart rate) of 620 ms and recurrent syncope. c.605-2A>G and c.815G>A (p.Gly272Asp) caused JLNS in a 12-year-old girl and her 5-year-old brother, showing QTc of 590 to 600 ms and recurrent syncope. The fourth JLNS case, a 46-year-old man carrying c.1032G>A (p.Ala344Alasp) and c.569G>A (p.Arg190Gln) and with QTc of 460 ms, has been syncope-free since age 30. His 16-year-old daughter carries novel missense mutation c.574C>T (p.Arg192Cys) and c.1032G>A(p.Ala344Alasp) and displayed a severe phenotype of Romano-Ward syndrome (RWS) characterized by a QTc of 530 ms and recurrent syncope with normal hearing. Both the father and daughter also carried c.253G>A (p.Asp85Asn; rs1805128), a rare single nucleotide polymorphism (SNP) on KCNE1. Bizarre T waves were seen in 3/4 JLNS patients. Symptoms were improved and T wave abnormalities became less abnormal after appropriate treatment. CONCLUSION: This study broadens the mutation and phenotype spectrums of JLNS. Compound heterozygous KCNQ1 mutations can result in both JLNS and severe forms of RWS in Chinese individuals.
ABSTRACT
Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited heart muscle disease associated with increased risks of sudden death, particularly in young, otherwise healthy, patients. The pathologic features are progressive myocardial atrophy and fibrofatty replacement. Plakophilin-2 (PKP2) is reported as the most common ARVD/C-causing gene in Western countries. In this study we aimed to determine the prevalence of PKP2 mutations in Chinese patients with ARVD/C and their phenotype characteristics. Genotype and phenotype were investigated in a cohort of 18 unrelated Chinese patients with a clinical diagnosis of ARVD/C. Direct sequencing of PKP2 led to the identification of 5 novel heterozygous mutations (R158K, Q211X, L419S, A793D, and N852fsX930) in 39% of patients (7 of 18) with ARVD/C. Among them, N852fsX930 was found in 3 unrelated young patients who presented with symptomatic ventricular tachyarrhythmia. Nevertheless, no significant difference could be detected between patients with ARVD/C with (n = 7) and without (n = 11) PKP2 mutations with regard to the phenotype characteristics and clinical outcomes. Decreased penetrance was prominent in family members. In conclusion, 5 novel PKP2 mutations were identified in a cohort of symptomatic Chinese patients with ARVD/C. N852fsX930 appeared to be a hot-spot mutation in which patients presented with a severe ARVD/C phenotype, and 2/3 had early onset of arrhythmic events. No significant difference was found in phenotype characteristics between patients with ARVD/C with and without PKP2 mutations. The decreased penetrance indicated that an ARVD/C diagnosis cannot solely rely on genotyping results.
Subject(s)
Arrhythmogenic Right Ventricular Dysplasia/genetics , Cardiomyopathies/genetics , Mutation/genetics , Plakophilins/genetics , Adult , Age of Onset , Arrhythmogenic Right Ventricular Dysplasia/physiopathology , Cardiomyopathies/physiopathology , China , Electrocardiography , Female , Genotype , Heterozygote , Humans , Male , Pedigree , PhenotypeABSTRACT
We describe a 45-year-old Asian man with Brugada-type 2 electrocardiogram and probable nocturnal agonal respiration. After genetic screening, drug challenge test and polysomnography examination, we ruled out Brugada syndrome and identified obstructive sleep apnea-hypopnea syndrome. Therefore, obstructive sleep apnea-hypopnea syndrome should be considered as a rare differential diagnosis for Brugada syndrome.