Creatine Phosphokinase Measurements Research Articles

Evaluation Of The Effectiveness of Dantrolene Sodium against Digoxin-Induced Cardiotoxicity In Adult Rats.

Digoxin poisoning commonly occurs in people treated with digoxin. It has been suggested that treatment with dantrolene may be a suitable strategy for digoxin-induced cardiotoxicity. The aim of this study was to evaluate the protective effect of dantrolene on digoxin-induced cardiotoxicity in male rats. This study was approved by the ethics committee of Birjand University of Medical Sciences (Ethical number: IR.BUMS.REC.1400.067). Forty-two Wistar rats weighing between 300- 350 gr were randomly allocated to 7 groups (n=6) as follows:Normal Saline (NS) group, Normal Saline + Ethanol (NS + ETOH) group), Normal Saline + dantrolene 10 mg/kg (NS + Dan 10) group, Digoxin (Dig) group), Digoxin + dantrolene 5 mg/kg (Dig + Dan 5) group),Digoxin + dantrolene 10 mg/kg (Dig + Dan 10) group), Digoxin + dantrolene 20 mg/kg (Dig + Dan 20) group), Dig was injected intravenously at 12 mL / h (0.25 mg / mL). Dan (5, 10 and 20 mg/kg) was injected intravenously at 5-8 min/mL. After 1 hour, blood samples were obtained from the animals&#38;#039; cavernous sinus and each animal&#38;#039;s heartremoved. The blood sample was rapidly centrifuged at 2,500 rpm for 10 minutes and the serum was separated for measurement of creatine phosphokinase (CPK), potassium (K), sodium (Na), calcium (Ca), and magnesium (Mg). The samples were stored at -20 oC. The heart samples were fixed in formalin 10% for histopathological evaluation. K levels slightly increased in the dig group versus the NS group. A significant increase in the K levels was observed in the Dig + Dan 20 group versus the NS group (p &#60; 0.001). dig slightly decreased Ca levels in the treated group versus the NS group. The levels of Ca significantly increased in the Dig + Dan 10 group versus the Dig group (p < 0.05). Histological examination of the heart tissue in the dig group showed cardiomyocyte degeneration, increased edematous intramuscular space associated with hemorrhage, and congestion. Focal inflammatory cell accumulation in the heart tissue was also seen. Cardiomyocytes were clear and arranged in good order in the Dig + Dan 10 group. dantrolene (10 mg/kg) was cardioprotective in a model of digoxin-induced cardiotoxicity, secondary to cardiac remodeling and hyperkalemia. However, further research is necessary to determine dantrolene&#38;#039;s cardioprotective and cardiotoxic doses in animal models.

Haff Disease in Salvador, Brazil, 2016-2021: Attack rate and detection of toxin in fish samples collected during outbreaks and disease surveillance

From late 2016 to early 2021, cases of Haff disease, a rare cause of rhabdomyolysis, possibly due to poisoning by palytoxin-like compounds in seafood, were detected in Salvador, Brazil. Surveillance was established to detect additional cases aiming at describing the clinical characteristics of the cases, identifying associated factors, estimating disease attack rate, and investigating the presence of biotoxins and trace metals in selected fish specimens obtained from cases. Between December/2016-January/2021, surveillance investigated Haff disease suspected cases, and obtained clinical and fish samples to test. Of 65 cases investigated during the 2016-2017 outbreak, 43 (66%) had high creatine phosphokinase (CPK) levels. Among those with laboratory-confirmed rhabdomyolysis, 38 (88%) were hospitalized, 11 (26%) required intensive care, and three (7%) dialysis. Ingestion of marine fish 24h before disease onset was reported by 74% of the cases with elevated CPK and by 41% of those without CPK measurement (P=0·02). Attack rate for individuals who ate fish related to the outbreak was 55%. Following this outbreak, surveillance identified 12 suspected cases between 2017-2019, and a second outbreak in 2020-2021, with 16 laboratory-confirmed rhabdomyolysis patients (five required intensive care; one died). No traces of ciguatoxins and metals were detected in fish specimens obtained in 2016, found to be Seriola rivoliana. Some fish samples from 2020 were screened for palytoxin (PlTX)-like compounds and contained detectable levels of molecule fragments characteristics of isobaric PlTX, ovatoxin-a (OVTX-a), OVTX-b and OVTX-d. These findings support the hypothesis that compounds related to PlTX accumulated in marine fish may be the toxic agent causing the disease. Haff disease is a life-threatening condition, requiring clinical suspicion for patients with sudden-onset myalgia following fish ingestion. Suspected cases should be reported to health authorities for investigation.

Absence of significant clinical benefit for a systematic routine creatine phosphokinase measurement in asymptomatic patients treated with anti-programmed death protein (ligand) 1 immune checkpoint inhibitor to screen cardiac or neuromuscular immune-related toxicities

AimDespite unprecedented results of anti-programmed death protein (ligand) 1 (PD-(L)1) immune checkpoint inhibitor in the oncology's armamentarium, immune-related adverse events (irAEs) represent a therapeutic hurdle. Currently, there is no consensual recommendation on a routinely monitored biomarker to early detect irAE. Biological markers such as serum creatine phosphokinase (CPK) are commonly used to measure muscular tissue injury. The potential of routine serum CPK monitoring to predict cardiac or neuromuscular irAE in patients treated with immunotherapy remains unknown. MethodsIn this retrospective study between January 2016 and December 2018 at Gustave Roussy Cancer Campus, 1151 cancer patients treated with anti-PD–(L)1 immunotherapy were systematically monitored with serum CPK measurements before each immunotherapy cycle. We considered significant CPK increases according to Common Terminology Criteria for Adverse Events v5.0 (CTCAEV5) of grade ≥2 severity. Comparisons were performed in patients with immune-related CPK (ir-CPK) elevations symptomatic versus asymptomatic. ResultsOverall, 53 of 1151 (4.6%) patients showed a CPK increase. Elevations of CPK were deemed to be immunotherapy-related in 31 of 1151 (2.7%) patients. Among them, 12 of 31 (38.7%) patients experienced symptomatic cardiac or neuromuscular irAE, whereas the other 19 of 31 (61.3%) patients remained asymptomatic. In patients with symptomatic irAE, the mean ir-CPK level was higher compared with asymptomatic patients (1271 versus 771 UI/L, P value = 0.02). In the asymptomatic group, all patients experienced a spontaneous resolution of the ir-CPK increase, and none required medical intervention. ConclusionMost patients with immune-related CPK increase remained asymptomatic. The CPK serum increase did not alter the clinical management of asymptomatic patients. The results of this study did not support a significant clinical interest for a systematic routine CPK monitoring in patients amenable to anti-PD-(L)1 immunotherapy.

Creatine phosphokinase, a new marker in diagnosis of tubal ectopic pregnancy; A Systematic Review.

Creatine phosphokinase (CPK) is an intracellular enzyme found in higher levels in the brain, myocardium, soft muscle and skeletal muscle, as well as the fallopian tube. This review was conducted to evaluate the role of serum CPK in early diagnosis of tubal ectopic pregnancy (EP). We performed an electronic literature search in Web of Science, Scopus, Embase and Medline databases and manual search in Google scholar and evaluated papers from the beginning of 1990 to September 2018. The inclusion criteria consisted of cohort, case-control and diagnostic value studies in English or Persian. Two independent researchers used the inclusion and exclusion criteria. In cases where there was doubt about the eligibility of studies, this problem was resolved by consulting a third researcher. After a thorough search, finally, we found 27 papers. However, four of these articles did not have the inclusion criteria and we excluded them from the study. As a result, 24 studies were evaluated. Most studies have approved the use of CPK measurements in EP diagnosis. The main variable measured in most studies was the mean total CPK level. However, there is limited knowledge about the efficacy of measuring CPK levels in EP diagnosis; this review of studies shows positive results regarding use of CPK in EP diagnosis. The results highlighted the potential benefits of CPK as a marker for early diagnosis of EP.

Safety and feasibility of a neuromuscular electrical stimulation chronaxie-based protocol in critical ill patients: A prospective observational study

PurposeThe aim of this study was to evaluate the safety and feasibility of a neuromuscular electrical stimulation (NMES) protocol based on neuromuscular excitability and applied in numerous muscle groups of critical ill patients. Materials and methodsWe performed a prospective observational study using an NMES applied daily and bilaterally into 5 muscle groups in lower limbs for 3 consecutive days. The characteristics of NMES were 90 contractions per muscle, pulse width equal to chronaxie, and a pulse frequency of 100 Hz. We assessed safety with central venous oxygen saturation, serum lactate, and creatine phosphokinase measurements. To evaluate feasibility, we recorded the time spent for the entire NMES protocol and the number of NMES sessions completed. ResultsEleven male patients finished the study. There were no significant changes observed in creatine phosphokinase from baseline up to 96 hours: 470(±270) IU/L and 455(±240) IU/L (P>.99). Central venous oxygen saturation and serum lactate had the same pattern with no significant variations (P=.23 and P=.8, respectively). The time spent during the whole procedure and the number of complete NMES sessions performed were 107±24 minutes and 84 sessions (85%), respectively. ConclusionsWe demonstrated that NMES chronaxie-based protocol is safe and feasible.

Adverse Drug Reactions, Medication Adherence and Physicians’ Prescribing Behavior: Which Relationship? a Database Analysis on Statin use

Pharmacological treatment plays an essential role in controlling chronic conditions such as hypercholesterolemia; however, patients' adherence to long-term therapies for chronic diseases is crucial to achieve optimal health outcomes (1). Further than medication adherence, pharmacological care is affected by the prescribing inappropriateness and adverse drug reactions (ADRs) (2). ADRs can lead to a perceived lack of therapy effectiveness and subsequent suboptimal adherence. Conversely, poor adherence to chronic disease medications may potentially lead to adverse drug events (ADEs), suggesting a bidirectional causal link between non-adherence to prescribed drug therapy and ADEs/ADRs occurrence (6). In the last decade, the use of statins showed a positive trend in Italy, consistently with the recent revisions of the statin reimbursement criteria (NOTA 13) by the Italian Medicines Agency (Agenzia Italiana del Farmaco) (3). Nevertheless, recent real practice analyses documented suboptimal rates of adherence to statin therapy in different Italian outpatient settings (4;5), resulting in poor low-density lipoprotein cholesterol (LDL-C) control, increased risk for cardiovascular events and increasing healthcare costs. For this reason, we explored the association between serum level of the enzyme creatine phosphokinase (CPK), the number of its measurements and adherence to statin therapy in a large Italian cohort of dyslipidemic patients, with the ultimate aim to evaluate the impact of statin-induced, muscle-related ADRs on patients' therapy adherence, and how this relationship may compromise the efficacy of physicians' prescribing choices and health outcomes in clinical practice. A retrospective cohort study was performed using data from databases of 4 Local Health Units (LHUs) located in Emilia-Romagna, Toscana and Umbria regions, with an overall population of about 1.1 millions of inhabitants. All subjects aged ≥ 18 years with a first prescription for statins in the period between January 1, 2007 and June 30, 2008 were included. All statin prescriptions over a 12 months follow-up period were analyzed to assess treatment adherence. Baseline and follow-up LDLC levels were considered. All CPK measurements in the follow-up period were analyzed. A total of 71855 patients (51% men, average age 68.6 ± 10.6 years) were included. Among them, 31544 (43.9%) were monitored for LDL-C at least one time during the follow-up period: only 37.4% of these patients achieved LDL-C target. 23.6% of patients underwent at least one serum CPK measurement: out of range values were identified in 37.8% of them. However, they were not switched to other statin drug and/or dosage. Depending on the increase of CPK measurements, patients with steadily normal values of CPK showed a better medication-taking behavior compared to patients whose CPK values were out of normal range. Furthermore, a greater percentage of switching to other statin drug and/or dosage was observed in patients with out of range CPK levels compared to those with normal serum CPK levels. Our findings indicate that physiological serum CPK levels were associated with greater adherence to statin therapy, supporting a causal link between non-adherence behavior and muscle-related ADRs occurrence. Since statin benefits are associated with their chronic use, physicians should be aware about the relevance of monitoring their patients for this harmful link to prevent unsuitable therapeutic decisions, further decreasing adherence, and achieve long-term health outcomes.

Predictors and outcomes of increases in creatine phosphokinase concentrations or rhabdomyolysis risk during statin treatment

The aim was to evaluate clinical risk factors associated with myotoxicity in statin users. This was a cohort study of patients prescribed a statin in UK primary care practices contributing to the Clinical Practice Research Datalink. Outcomes of interest were creatine phosphokinase (CPK) concentrations and clinical records of rhabdomyolysis. The cohort comprised 641,703 statin users. Simvastatin was most frequently prescribed (66.3%), followed by atorvastatin (24.4%). CPK was measured in 127,209 patients: 81.4% within normal range and 0.7% above <four times the upper limit of normal (ULN). Rhabdomyolysis was recorded in 59 patients. Patients with concomitant prescribing of CYP3A4-interacting drugs had an increased odds ratio (OR) of rhabdomyolysis compared with controls (OR 3.71, 95% CI 1.18, 11.61) and >four times ULN CPK compared with normal CPK (OR 1.28, 95% CI 1.01, 1.60). Rosuvastatin users had higher risk of >four times ULN CPK (OR 1.62, 95% CI 1.22, 2.15) as did patients with larger daily doses of other statin types. A recent clinical record of myalgia was associated with an increased OR of >four times ULN CPK (OR 1.73, 95% CI 1.37, 2.18). In patients who were rechallenged to statins and had repeat CPK measurements after >four times ULN CPK abnormalities, 54.8% of the repeat CPK values were within normal range, 32.1% between one to three times and 13.0% >four times ULN. The frequencies of substantive CPK increases and rhabdomyolysis during statin treatment were low, with highest risks seen in those on large daily doses or interacting drugs and on rosuvastatin. CPK measurements appeared to have been done in a haphazard manner and better guidance is needed.

Predicting the Outcomes of Rhabdomyolysis

Predicting the Outcomes of Rhabdomyolysis

Cardiac complications and immunophenotypic profile of infectious mononucleosis syndrome in children

To investigate cardiac complications in infectious mononucleosis patients and to associate them with biochemical and immunological parameters, as well as with spleen ultrasound findings. Cross-sectional study with follow-up. Tertiary care pediatric unit, in the city of Thessaloniki, Greece. Twenty-five children (15 boys, aged 1-11.6 years) suffering from infectious mononucleosis were studied during the acute phase and after 3-6 months. Cardiac evaluation comprised of electrocardiogram, echocardiogram, and measurement of creatine phosphokinase, creatine phosphokinase cardiac isoenzyme, and troponin levels. Biochemical and immunological tests included serum transaminases, serum amylase, CD3+/CD8+ T-lymphocytes subpopulation and CD4+/CD8+ T-lymphocytes ratio. During acute phase, all children had splenomegaly and normal serum amylase values. 17 patients had elevated serum transaminases. Percentages of CD3+/CD8+ T-lymphocytes subpopulation were elevated and CD4+/CD8+ ratio was decreased in all patients. Echocardiography revealed mild pericardial effusion in 13 patients (10/21 with Epstein-Barr infection, 3/4 with cytomegalovirus infection), but none presented with myocarditis. Four out of these 13 patients also had markedly elevated liver enzymes, 10/13 had significant splenomegaly and 12/13 presented very low CD4+/CD8+ T-lymphocytes ratio. Pericardial effusion demonstrated a statistically significant association solely with very low CD4+/CD8+ T-lymphocytes ratio (<0.5). Repetition of laboratory tests 3-6 months post-discharge detected persistent mild pericardial effusion in five patients, along with decreased CD4+/CD8+ ratio in 1/5. In infectious mononucleosis syndrome, asymptomatic pericardial effusion could be associated with very low CD4+/CD8+ ratio (<0.5). Further studies would extend and confirm such an association.

Biological Perspectives

He's gone country Everybody's gone country Yeah we've gone country The whole world's gone country --Alan Jackson Psychotropic drugs are in. Even psychiatric nurses who once considered psychotropic drugs a necessary evil or a treatment of last resort, now embrace the inevitability of the times--the fusion of public expectations, third-party considerations, and time constraints. As a result, psychotropic medications have become firstline options in treatment. However, several serious and potentially fatal side effects are related to these agents--for example, neuroleptic malignant syndrome, serotonin syndrome, and agranulocytosis. All these adverse responses were discovered the fact: that is, these effects were not anticipated but were described after patients had developed symptoms or had died. With careful assessments demanded by unacceptable levels of morbidity and mortality, both incidence and death rates have dropped significantly in recent years. Rather than risk allowing these catastrophic consequences to drift to the periphery of practice, we attempt in the following pages to bring the discussions up to date. Neuroleptic Malignant Syndrome Neuroleptic malignant syndrome (NMS) is a potentially fatal reaction to dopamine blockade caused by antipsychotic and other medications. The majority of these medications are prescribed in the treatment of schizophrenia and work by antagonizing dopamine D2 receptors (Keltner & McIntyre, 1985). Although uncommon, NMS may be fatal if left untreated. Estimates of the incidence of NMS range from 0.5% to 2.4%, and the mortality rate may be as high as 20% in those who are not treated (Reeves, Mack, & Torres, 2001). Persing (1994) identified four cardinal symptoms of NMS: hyperthermia, muscle rigidity, mental status changes, and autonomic instability. NMS most often occurs with high potency antipsychotics, and was first described during clinical trials with haloperidol in 1960 (Reeves, Torres, Liberto, & Hart, 2002). Although haloperidol has been most often implicated, cases also are reported with atypical antipsychotic and other dopamine receptor-blocking medications (Beauchemin, Millaud, & Nguyen, 2002; Harradine, Williams, & Doherty, 2001; Philibert, Adam, Frank, & Carney-Doebbeling, 2001; Solomons, 2002). Ninety-six percent of NMS cases occur within the first 30 days of treatment (Persing), with a duration of 5 to 10 days after antipsychotic medications are discontinued (Lappa et al., 2002). Dopamine and NMS. Dopamine is a catecholamine. It has as its immediate precursor levodopa and is itself a precursor to norepinephrine. Dopamine is synthesized from the amino acid tyrosine, which crosses the blood brain barrier and is converted to levodopa in dopaminergic and noradrenergic neurons. Dopamine's metabolic pathway, then, may be summarized as: tyrosine [right arrow] levodopa [right arrow] dopamine [right arrow] norepinephrine (Keltner, Hogan, & Guy, 2001). Pathophysiology of NMS. Central nervous system dopamine is localized in four specific pathways. Altered functioning in two of these pathways is thought to induce the positive and negative symptoms of schizophrenia. Treatment strategies aimed at manipulating dopamine affect all four tracts. Chemical manipulation of three of these pathways may contribute to NMS (Table 1). Some of these symptoms of NMS are interrelated. For example, high temperatures may develop and can be exacerbated by massive muscle contraction and hypermetabolism (Lappa et al., 2002). Rigidity also may cause rhabdomyolysis, which can lead to acute renal failure when kidneys are flooded with myoglobin. Severity is assessed by measurement of creatine phosphokinase (CPK). Renal failure is the most common cause of death in NMS (Persing, 1994). Mental status changes can be an early sign of NMS and may progress to coma. Changes in mental status may be characterized by delirium, catatonia, and agitation. …

Elevated serum creatine phosphokinase in choline-deficient humans: mechanistic studies in C2C12 mouse myoblasts

Choline is a required nutrient, and humans deprived of choline develop liver damage. This study examined the effect of choline deficiency on muscle cells and the release of creatine phosphokinase (CPK) as a sequela of that deficiency. Four men were fed diets containing adequate and deficient amounts of choline, and serum was collected at intervals for measurement of CPK. C2C12 mouse myoblasts were cultured in a defined medium containing 0 or 70 micromol choline/L for up to 96 h, and CPK was measured in the media; choline and metabolites were measured in cells. Apoptosis was assessed by using terminal deoxynucleotidyl transferase-mediated dUTP-biotin end labeling and activated caspase-3 immunohistochemistry. Cell fragility in response to hypo-osmotic stress was also assessed. Three of 4 humans fed a choline-deficient diet had significantly elevated serum CPK activity derived from skeletal muscle (up to 66-fold; P < 0.01) that resolved when choline was restored to their diets. Cells grown in choline-deficient medium for 72 h leaked 3.5-fold more CPK than did cells grown in medium with 70 micromol choline/L (control medium; P < 0.01). Apoptosis was induced in cells grown in choline-deficient medium. Phosphatidylcholine concentrations were diminished in choline-deficient cells (to 43% of concentrations in control cells at 72 h; P < 0.01), as were concentrations of intracellular choline, phosphocholine, and glycerophosphocholine. Cells grown in choline-deficient medium had greater membrane osmotic fragility than did cells grown in control medium. Choline deficiency results in diminished concentrations of membrane phosphatidylcholine in myocytes, which makes them more fragile and results in increased leakage of CPK from cells. Serum CPK may be a useful clinical marker for choline deficiency in humans.

Ação do ácido trissódio-cálcio-dietileno-triaminopentaacético (CaNa3DTPA) nas lesões de isquemia-reperfusão em membro posterior de rato

OBJETIVO: Ação do ácido trissódio-cálcio-dietileno-triaminopentaacético (CaNa3DTPA), quelante de ferro com ação ainda anti-viral, antiinflamatória e imunológica, na atenuação de lesões de reperfusão em músculos esqueléticos de ratos. MÉTODOS: 52 ratos Wistar, pesando 188±22g, foram anestesiados e submetidos a semi-amputação de membro posterior direito (MPD), poupando-se o fêmur, artéria e veia femorais. Foram então randomizados e distribuídos: G1-CTAN - controle anestesia, sem cirurgia e sem isquemia; G2-CTCIR - controle cirurgia, sem isquemia; G3-IRCT e G3-IRDTPA - com isquemia (4 hora) e reperfusão ( 2 horas). O G3-IRCT foi tratado, ao final da isquemia, com cloreto de sódio 0,9% e G3-IRDTPA com (CaNa3DTPA).Parâmetros: Circunferência do pé direito e peso do rato, dosagem sérica de CPK, dosagem de malonaldeído e microscopia óptica de músculos soleus bilateral. RESULTADOS: Aumento da circunferência nos G3-IRCT e G3-IRDTPA (significante no G3-IRCT quando comparado ao G1-CTAN); CPK elevado nos G3-IRCT e G3-IRDTPA comparados aos controles; MDA mais alto no membro contralateral do G3-IRDTPA, comparado ao MPD do G3-IRDTPA e ao G1-CTAN; maior edema intersticial em G3-IRCT, maior infiltrado inflamatório em G3-IRDTPA e recuperação dos níveis de glicogênio semelhantes em G3-IRCT e G3-IRDTPA. CONCLUSÃO: Apesar do menor edema no G3-IRDTPA comparado ao G3-IRCT, o CaNa3DTPA não alterou CPK sérico, MDA muscular e morfologia muscular dos animais.

Efeitos do alfa-tocoferol nas lesões de isquemia-reperfusão induzidas em pata direita de ratos

Recentes estudos demonstraram que os radicais livres de oxigênio parecem desempenhar papel importante nas lesões de isquemia-reperfusão. O alfa-tocoferol(AT) age in vivo como um anti-oxidante. Nosso objetivo foi o de verificar se o AT atenuava as lesões de isquemia-reperfusão em pata direita de ratos. Os animais, randomizados, foram divididos nos seguintes grupos(G): G1-controle sem isquemia; G2 e G3 - quatro horas isquemia e duas reperfusão. Os animais do G2 foram tratados com salina e os do G3 com AT, 50mg/kg. Como parâmetros examinamos as alterações de volume e circunferência do pé direito ao longo do experimento, assim como a captação de 99mTc-pirofosfato e a microscopia eletrônica de transmissão do músculo soleus direito. Os aumentos de volume e circunferência do pé dos animais do G2 foram estatisticamente maiores quando comparados com o G1. As medidas do G3 não diferiram do G1. A captação de 99mTc-pirofosfato foi bem aumentada nos G2 e G3, quando comparados ao G1, porém sem diferenças entre os grupos isquêmicos. As lesões ao MET foram menos intensas em três animais do G3, quando comparados ao G2. Conclusão: O tratamento com AT diminuiu a formação do edema mas só protegeu parcialmente as células musculares contra as lesões de isquemia-reperfusão.

Rhabdomyolysis in Patients with Hypoglycemic Coma. Three Cases Study.

We showed the three cases in rhabdomyolysis according to hypoglycemic coma. The measurements of creatine phosphokinase, creatine phosphokinase isozyme, myoglobin, and cardiac myosin light chain I are useful for diagnosing the rhabdomyolysis in patients with diabetes mellitus.

Sperm creatine kinase activity in normospermic and oligozospermic Hungarian men.

Our purpose was to measure sperm creatine phosphokinase (CK) activity, which reflects cytoplasmic retention in immature spermatozoa, in normospermic and oligozospermic Hungarian men. A study of 109 randomly selected men in a university-based andrology laboratory was done. CK activity differed between normospermic and oligozospermic men (0.21 +/- 0.02 vs. 1.19 +/- 0.15 CK IU/10(8) sperm; n = 56 and n = 53; mean +/- standard error of the mean, respectively). There was an inverse correlation between sperm concentration and CK activity (r = -0.70; n = 109). However, 28% of men in the range with less than 10 million sperm/ml had normal sperm CK activity (below the mean + 2 standard deviations of the group with greater than 30 x 10(6) sperm/ml), whereas 36% of men in the group with 20-30 million sperm/ml and 5% in the group with greater than 30 million sperm/ml had elevated CK activities, indicating that the incidence of mature and immature spermatozoa in specimens is independent from the sperm concentrations. The improved facility of sperm CK activity measurements, compared with sperm concentrations, in the assessment of sperm maturity was confirmed in a Hungarian population. The CK measurements aid the selection of the most efficient treatment for couples with male-factor or unexplained infertility, particularly when considering the options of intrauterine insemination, varicocelectomy followed by a waiting period, or ovulation workup/induction in wives of men who are oligozospermic but may have fertile sperm.

Recurrence pattern of serum creatine phosphokinase levels in repeated acute psychosis

Elevated serum creatine phosphokinase (CPK)MM level is frequently found in acute psychosis. Theories relate this CPKemia to psychomotor agitation and medication. We hypothesized that psychosis-related CPKemia observed in individual patients is relatively consistent. Ninety psychotic patients were studied; 83% were schizophrenics (Brief Psychiatric Rating Scale scores > or = 40) whose serum CPKMM levels were recorded during two or more different acute psychoses. The serum CPKMM levels used were the maximal levels monitored during the beginning of each hospitalization. The last CPK measurement in a circumscribed period was defined as the index serum CPK level (IndCPK). The mean of all other individual maximal CPK measurements during other psychotic episodes was defined as the average CPK (AvgCPK). Multiple linear regression analysis showed a significant correlation of natural logarithm (Ln) of (IndCPK with Ln(AvgCPK), as well as with gender (coefficient = .65 and .63, p < .0001 and p < .01, respectively). There were significantly higher IndCPK levels among male patients than among female patients (p < or = .001). A relatively consistent individual pattern of serum CPKMM levels during repeated acute psychotic episodes was observed. Serum CPKMM levels and gender were found to be good predictors of maximal serum CPKMM levels during every repeated acute psychotic episode. High IndCPK levels are probably risk factors for neuroleptic malignant syndrome.

Effects of Physical Activity on Creatine Phosphokinase and the Isoenzyme Creatine Kinase–MB

Creatine phosphokinase (CPK) and creatine kinaseMB (CK-MB) have been used extensively as diagnostic markers for myocardial infarction and skeletal muscle injury. Many factors affect the variability of serum CPK and serum CK-MB activity, especially physical activity. We discuss the influence of physical activity on muscle and serum CPK and CK-MB. The effect of acute and chronic exercise on CPK and CK-MB activity emphasizes the need to use measurements of serum CPK and CK-MB with caution when evaluating and diagnosing acute myocardial infarctions and skeletal muscle injury.[Schneider CM, Dennehy CA, Rodearmel SJ, Hayward JR: Effects of physical activity on creatine phosphokinase and the isoenzyme creatine kinaseMB. Ann Emerg Med April 1995;25:520-524.]

The importance of N-linked glycoproteins and dolichyl phosphate synthesis for fusion of L6 myoblasts.

Myoblasts fuse to form multinucleated myotubes, one of the early steps in the formation of multinucleated muscle fiber. The fusion reaction is accompanied by biochemical differentiation resulting in the expression of a variety of enzyme activities and macromolecules, particularly creatine phosphokinase. The fusing myoblast is thus an excellent system for use in studies on the molecular basis of cellular recognition. This report focuses on the role played by glycoproteins in this process. It was found that alteration of cell-surface glycoproteins, using oligosaccharide-processing inhibitors that interfered with the synthesis of the high-mannose type of N-linked oligosaccharide, resulted in the inhibition of both the fusion reaction and biochemical differentiation as determined by measurement of creatine phosphokinase. Ketoconazole, compactin, and lovastatin, which affect dolichol and cholesterol biosynthesis, were also potent fusion inhibitors. These observations, coupled with earlier studies on the characterization of fusion-defective myoblast cell lines defective in glycoprotein biosynthesis, point to the importance of surface glycoproteins in cellular recognition in L6 myoblasts.

Selective degradation of mRNA: the role of short-lived proteins in differential destabilization of insulin-induced creatine phosphokinase and myosin heavy chain mRNAs during rat skeletal muscle L6 cell differentiation.

This investigation concerns the combined effects of removal and readdition of insulin and inhibition of protein and RNA synthesis on the stability of insulin-induced mRNAs during and after differentiation of rat L6A1 myoblast cells in culture. Addition of insulin accompanying the withdrawal of the mitogenic stimulus of serum to myoblasts caused an 80-fold increase in creatine phosphokinase (CK) activity which was largely accounted for by a similar increase in the amount of CK mRNA. The latter was co-ordinately induced with myosin heavy chain (MHC) mRNA but not malic enzyme (ME) mRNA. Measurements of steady-state levels of mRNA showed that removal of insulin caused CK mRNA, but not MHC mRNA, to be rapidly degraded, the effect being reversed upon readdition of the hormone. Direct measurement of 3H-labeled CK, MHC and beta-actin mRNAs confirmed the selective stabilization and destabilization of CK mRNA by the hormone. Conditions were established for a time-window during which cycloheximide (Cx) produced a virtually total arrest of protein synthesis in myotubes that was reversible upon removal of the inhibitor. Under these conditions, Cx selectively prevented the degradation of CK mRNA in a reversible manner. Actinomycin D (Act D) also arrested the loss of this mRNA. Under the same conditions of mRNA stabilization during de-induction, a superinduction of CK mRNA, but not MHC mRNA, was observed if the two inhibitors were added during induction in the continuous presence of insulin. We conclude that a short-lived protein(s), encoded by a short-lived mRNA(s), selectively regulates the stability of reversibly inducible mRNA.

Strength training for prepubescent males: is it safe?

This study examined the safety of one type of strength training for prepubescent males. Eighteen males (average age, 8.3 +/- 1.2 years) participated in a 45 min/session, three session/week, 14 week supervised strength training program with an attendance rate of 91.5%. Concentric work was done almost exclusively. KinCom analysis showed significant strength gain in this group (P less than 0.05), while an age, sex, and activity matched control group did not gain strength. Safety was evaluated by injury surveillance, blood pressure and heart rate monitoring, scintigraphy, and creatine phosphokinase measurement. Effects on growth and development, flexibility, and motor performance were also investigated, as these are factors with an impact on sports injury occurrence. Results showed that in the short term, supervised concentric strength training results in a low injury rate and does not adversely affect bone, muscle, or epiphyses; nor does it adversely affect growth, development, flexibility, or motor performance. As the safety question is multifaceted, this should not lead to the conclusion that strength training for prepubescents is uniformly safe. Further research is needed.