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PubMed2004

The role of repeat uterine evacuation in the management of persistent gestational trophoblastic disease.

OBJECTIVE: To evaluate the role of second (and third) uterine evacuation in the management of persistent gestational trophoblastic disease (GTD). METHODS: This was an observational study of all cases registered over a 10-year period at the Trophoblastic Disease Centre at Weston Park Hospital, Sheffield. Five hundred and forty-four of 4050 women registered during 1991-2000 underwent a second uterine evacuation following a presumptive diagnosis of persistent GTD. The reason for evacuation, hCG level prior to the procedure, histological appearances of evacuated products and the clinical outcome (in terms of the need for chemotherapy) were determined. RESULTS: After a second uterine evacuation 368 patients (68%) completed the follow-up programme without further evidence of persistent disease or need for chemotherapy. If the diagnosis of persistent GTD was confirmed solely on the basis of elevated hCG levels then 171 of 282 (60%) patients did not require chemotherapy. Chemotherapy was more likely where there was histological evidence of persistent trophoblastic disease and where the urinary hCG was >1500 IU/L at the time of the repeat evacuation. Twenty-eight of 60 patients (46%) undergoing a third evacuation required chemotherapy. CONCLUSION: Second uterine evacuation can be a useful therapeutic option for patients with presumed persistent trophoblastic disease not mandating immediate chemotherapy, particularly where the hCG level is <1500 IU/L. Patients with documented persistent trophoblastic disease on histological examination of the second evacuation sample are more likely to require chemotherapy. Third evacuation is not now recommended.

Adolescent↗
PubMed1998

Effects of propanolol in patients entered in the Beta-Blocker Heart Attack Trial with their first myocardial infarction and persistent electrocardiographic ST-segment depression.

OBJECTIVE/BACKGROUND: It has been shown that patients with an acute myocardial infarction and persistent electrocardiographic ST-segment depression are at high risk for subsequent cardiac events. The purpose of this retrospective analysis was to examine the long-term effects of propranolol therapy in patients with their first acute myocardial infarction and persistent electrocardiographic ST-segment depression. METHODS: The outcomes of 2877 patients enrolled in the Beta-Blocker Heart Attack Trial (BHAT) with their first myocardial infarction (75% of patients in BHAT) were reviewed. Patients were divided into three groups on the basis of presence or absence of > or =1 mm ST-segment depression in two contiguous leads of the 12-lead electrocardiogram obtained soon after admission or at the time of randomization, which occurred 10.1+/-3.5 days after the index myocardial infarction. Group 1 included 774 patients (392 randomly assigned to placebo and 382 to propranolol) with no ST-segment depression; group 2 included 1447 patients (713 placebo, 734 propranolol) with ST-segment depression at admission or at the time of randomization (labeled as transient); and group 3 included 656 patients (339 placebo and 317 propranolol) who had electrocardiographic ST-segment depression from the time of admission to the time of randomization (labeled as persistent). RESULTS: In group 3, patients with persistent electrocardiographic ST depression, the mortality rate in patients randomly assigned to placebo was 13.6% compared with 7.6% in patients with propranolol (p = 0.012; log rank test). Sudden death in the placebo arm was 9.7% compared with 4.7% in the propranolol group (p = 0.012, log rank test). The results of the Cox regression analysis, adjusting for all baseline variables with p values <0.25, showed the relative risk of overall mortality rate and the relative risk of sudden death were 2.13 ( 1.22, 3.70) and 2.56 (1.27, 5.26), respectively, for the placebo group compared with the propranolol group. Patients with persistent ST-segment depression had the greatest benefit from propranolol (47.2 fewer events [deaths/reinfarctions] per 1000 person-years compared with 78 and 2.1 fewer events in patients with transient and no ST-segment depression, respectively). CONCLUSIONS: It appears that the greatest benefit for beta-blocker therapy in patients after myocardial infarction is observed in patients with persistent ST-segment depression who are at greatest risk for death and reinfarction. Definitive conclusions regarding therapy with beta-adrenergic blocking agents in patients with persistent ST-segment depression cannot be made because our analysis, given its retrospective nature, is only hypothesis generating.

Adrenergic beta-Antagonists↗
PubMed2000

Prognostic significance of persistent right ventricular dysfunction as assessed by radionuclide angiocardiography in patients with inferior wall acute myocardial infarction.

We evaluated cardiac hemodynamics and long-term prognosis in patients with right ventricular (RV) acute myocardial infarction (AMI) using Fourier phase and amplitude analysis of radionuclide angiocardiographic scanning. In 143 patients with RV AMI, delayed phase and low amplitude in radionuclide RV images persisted in 54 patients (persistent RV dysfunction group) 3 months after AMI, but disappeared in the remaining 89 patients (improved RV function group). No significant differences were present in RV dimensions, left ventricular (LV) wall motion, LV ejection fraction, or RV ejection fraction between these groups during the acute phase. At 3 months, RV dimension and LV and RV wall motion indexes were significantly higher (p = 0.0292, p = 0.0124, p<0.0001, respectively), and LV and RV ejection fractions were lower (p = 0. 0174 and p = 0.0008, respectively) in the persistent RV dysfunction group. Percutaneous transluminal coronary angioplasty in the acute phase was performed in a smaller group of patients (15% vs. 34%, p = 0.0223), and the degree of residual stenosis in the proximal right coronary artery was significantly greater in the persistent RV dysfunction group than in the improved RV function group (82+/-22% vs. 53+/-30%, p<0.0001). The 8-year survival rate was significantly lower in the persistent RV dysfunction group (p<0.0001). Persistent abnormality of phase and amplitude in radionuclide RV images was a significant independent predictor of long-term survival (odds ratio 10.42; 95% confidence interval 3.65 to 29.71; p<0.0001). Radionuclide angiocardiographic Fourier phase and amplitude scanning can detect persistent RV dysfunction in patients with RV AMI and can predict patient outcome.

Aged↗
PubMed2001

Persistent vertical binocular diplopia after cataract surgery.

PURPOSE: To report the incidence of, and factors associated with, persistent vertical diplopia after cataract surgery. DESIGN: Consecutive interventional case series. METHODS: Retrospectively, all adult patients examined during a five year, five month period because of new onset persistent (>3 months) vertical binocular diplopia after cataract surgery were analyzed. All patients had their cataract surgery at the same outpatient ophthalmic surgery center, and were referred to the author, enabling calculation of incidence. Trends in anesthesia type and strabismus complications therefrom were also assessed. Comparison was made between ophthalmologist-administered retrobulbar anesthesia versus anesthesia staff-administered retrobulbar anesthesia. Incidence during a period in which hyaluronidase was not incorporated in the retrobulbar anesthetic was calculated. RESULTS: Persistent vertical diplopia occurred after cataract surgery in 32 (0.18%) of 17,531 eyes that had cataract surgery. No patient whose cataract surgery was conducted with topical anesthesia (3817 eyes) had persistent vertical diplopia, whereas 32 (0.23%) of the 13714 eyes whose cataract surgery was done after retrobulbar anesthesia were affected. No cases of persistent postoperative diplopia were found among 7410 cataract surgery eyes after retrobulbar injection given by one cataract surgeon. There was a threefold greater number of left eyes involved than right eyes (P <.005). No significant (P >.20) increase in cases of persistent vertical diplopia was noted during a period of hyaluronidase shortage. CONCLUSIONS: In this study, persistent binocular vertical diplopia after cataract surgery occurred in 0.23% of cases in which retrobulbar anesthesia was performed. No cases were found after topical anesthesia. Occurrence may be technique-related.

Aged↗
PubMed2002

MRI brain scan analyses and neuropsychological profiles of nine patients with persisting unilateral neglect.

Systematic individual neuroanatomical (MRI) and neuropsychological investigations were conducted for nine patients with unilateral neglect persisting at least 3 months after a cerebral vascular accident. The pattern of referrals, together with subsequent investigation, demonstrates that persisting neglect is rare in both right- and left-hemispheric lesioned patients. But while persisting neglect following a left-hemispheric lesion is even rarer than following a right-hemispheric lesion, it does occur. The neuroanatomical results indicate that persisting neglect may be associated with a different pattern of damage from acute neglect. In the nine patients investigated, persisting neglect reflected extensive lesions that involved three or more cortical lobes or subcortical regions. The results support previous findings that parietal lesions are common but not essential for persisting neglect. In the seven of nine neglect patients with parietal lesions, the rostral inferior parietal lobe and the parietal-frontal junction were involved. Of note was the finding that the brain regions most commonly implicated were the basal ganglia and the superior dorsolateral prefrontal cortex (including the frontal eye field). All of the patients with persisting neglect had a range of neuropsychological deficits, including extinction, personal neglect, and anosognosia for one or more aspects of their neglect. Although it was not possible to demonstrate a double dissociation with this pattern of results, the findings indicate that extinction and anosognosia are dissociable into function-specific forms. Most of the neglect patients also had sustained attention deficits, visual memory problems, and visuospatial constructional difficulties.

Adolescent↗
PubMed2000

Rate of persistent perforation after elective tympanostomy tube removal in pediatric patients.

This study was performed to determine the rate of persistent perforations according to age, tube type and duration of intubation in children who underwent elective tympanostomy tube removal. Our retrospective analysis of hospital and clinic charts included all patients who underwent elective tube removal from July 1995 to December 1997 at our institution. Information from the chart review included patient age at time of tube removal, type of tube removed, duration of intubation, presence of granulation tissue/polyps, and concomitant paper patch placement. The outcome of each surgical removal was determined by examining follow-up clinic charts. A patient was deemed to have a persistent perforation if the eardrum had not adequately healed within 3 months after surgery. Data on 201 patients were gathered. These patients had 273 tube removals. Eleven percent of ears (29/273) had persistent perforations. According to tube type, no perforations (0/48) occurred with Collar Bobbin tubes, 6% (3/50) with Tytan tubes, 7% (3/44) with Duravent tubes, and 22% (16/74) with Paparella II tubes. Three percent (3/101) of tubes in place for <3 years and 15% (26/172) of tubes in place for >3 years showed persistent perforations after removal. Ears with granulation polyps had a 9% (18/203) rate of perforations, whereas those without granulation polyps had a 16% (11/70) rate of perforations. Forty percent (4/10) of ears were treated with paper patches at the time of tube removal showed persistent perforations. Our data indicate that the rate of persistent perforation (11%) after elective tympanostomy tube removal is high. The factors associated with higher rates of persistent perforation (P<0.05) include duration of intubation >3 years prior to removal and the use of long-term Paparella II tubes.

Child↗
PubMed1998

Persistent infection with an influenza C virus variant is dominantly established in the presence of the parental wild-type virus.

Two influenza C viruses were used for double-infection experiments to investigate the dominance of their phenotypes. The wild-type virus (C/AA-wt) had been characterized by its short-lived productive cycle, whereas a distinct variant derived from it (C/AA-pi) was demonstrated to persist in long-term passages of infected MDCK cultures. Here we show that the persistent virus C/AA-pi is capable of replicating in the presence of abundant amounts of wild-type virus: the persistent virus could be diluted to 10(-9) within wild-type inoculum, still developing a stable form of persistence. This behaviour was reflected by permanent virus release and by continuous enzymatic activity of the viral HEF glycoprotein in infected cells. All long-term cultures tested remained positive for viral NS protein and vRNA. On the vRNA level, it was shown that viral segments originated from the persistent-type genome, while wild-type vRNAs were not maintained after double-infection. Thus, the genotype of the persistent variant was dominantly selected in serial passages. These results indicate a specific intracellular advantage of persistent influenza C virus over the parental wild-type.

Animals↗
PubMed1999

A persistent variant of influenza C virus fails to interact with actin filaments during viral assembly.

C/AA-pi virus, a variant of influenza C/Ann Arbor/1/50 virus, establishes persistent infections in MDCK cells, characterized by low levels of progeny production. During viral assembly, nucleoprotein (NP) was found homogeneously distributed over cytoplasmic and nuclear compartments and matrix (M) protein was likewise localized in a barely structured fashion. In contrast, infections with nonpersistent influenza A, B and C viruses produced cytoplasmic granular structures, which typically consisted of colocalized NP and M proteins. Studies on the in vitro interaction between NP and M proteins revealed identical binding capacities comparing influenza C wild-type virus with the persistent variant. Cytochalasin D treatment of infected cells demonstrated that NP protein of the wild-type virus, but not of the persistent variant, was distinctly associated with cellular actin filaments. Moreover, the assembly characteristics of wild-type virus were modulated in the presence of recombinant persistent-type NP protein towards a behaviour similar to persistent infection. Cell type specificity was particularly illustrated in C/AA-pi virus-infected Vero cells, which did not support viral persistence, but produced granular wild-type-like complexes. Thus, interaction between NP, M and actin proteins (i) is a basic part of the viral assembly process, (ii) is dominantly modulated by NP protein and (iii) is specifically altered in the case of persistent infection.

Actins↗
PubMed2000

The three-year persistence of depressive symptoms in men and women.

Little is known about sex differences in the course of depression. The results of the few surveys of the general population are inconsistent. Furthermore, the generalizability of most of these findings is limited. First, only a handful of studies of the general population use a prospective design to estimate the persistence of depression in women and men. Second, in some studies only particular subgroups of the general population are sampled, and finally, depression persistence is often measured using unconventional short time-intervals. Using data from five waves of the Flemish subsample of the Panel Study of Belgian Households (PSBH)--a probability sample of 1168 (52.5%) women and 1055 (47.5%) men--we tried to go beyond these shortcomings. Depression persistence is estimated using a self-report inventory on four occasions separated by intervals of one year (1993, 1994, 1995, 1996). Results show a significant influence of sex, other sociodemographic characteristics, and depression severity at baseline on three-year depression persistence. Women experience more chronicity, a difference that can be partially ascribed to sex differences in employment status, education and marital status. Persistence in linked to marital status in women. In men persistence is associated with level of education and with employment status. Depression severity at baseline, however, largely explains the influence of these social conditions on depression persistence.

Adolescent↗
PubMed2000

Evaluation of the persistent efficacy of doramectin and ivermectin injectable against Ostertagia ostertagi and Cooperia oncophora in cattle.

The persistent efficacy of doramectin and ivermectin injectable against moderate and high infection levels of Ostertagia ostertagi and Cooperia oncophora were evaluated in cattle. Calves were allocated to six groups of six animals. On Day 0 animals of Groups I1/I2 and D1/D2 were treated with 0.2mg/kg ivermectin and doramectin injectable, respectively. Animals of the C1, I1 and D1 groups received a daily (moderate) infection of 1000 L3 of O. ostertagi and 1000 L3 of C. oncophora, and animals of the C2, I2 and D2 groups received a daily (high) infection of 10,000 L3 of each species. The animals were infected for 21 days with both species, the infections with C. oncophora and O. ostertagi started from Days 8 and 15 post treatment, respectively. Animals were necropsied on Day 40. The calculation of the persistent activity of ivermectin and doramectin was based on the efficacy against the different developmental and adult stages of both parasites. The present study confirmed that infection levels may influence the duration of persistent efficacy of an anthelmintic. Doramectin had at the moderate infection level a persistent efficacy of at least 35 days against O. ostertagi and at least 28 days against C. oncophora; at the high infection dose persistent efficacy was somewhat shorter i.e. up to 33 days and approximately 28 days, respectively. The duration of persistent efficacy of ivermectin against O. ostertagi at the moderate infection level was between 14 and 25 days, at the high dose level up to 25 days. Persistent efficacy of ivermectin against C. oncophora could, at both infection doses, not be measured, with the present experimental design.

Animals↗
PubMed1998

Developmental patterns of heart rate and variability in infants with persistent apnea of infancy.

During periods of regular breathing, heart rate is slower and more variable in healthy (no history of respiratory distress syndrome) prematurely born infants with persistent apnea, relative to full-term control infants of comparable post-conceptional ages. We tested the hypothesis that the cardiovascular differences may be linked to the persistent apnea, rather than premature birth, by assessing heart rate and variability in full-term infants with persistent apnea. Thus, resting heart rate and variability were compared in full-term infants with apnea of infancy, prematurely born infants with persistent apnea, and full-term control infants. Full-term infants with persisting apnea showed slower heart rates than control infants, beginning at 4 months after birth, and enhanced heart rate variability beginning at 6 months. Healthy prematurely born infants with persistent apnea showed cardiovascular alterations similar to those of full-term infants with apnea; these alterations differed from those observed in very premature infants with histories of respiratory distress. The postnatal development of cardiovascular aberrations in infants with persistent apnea suggests that mechanisms accompanying apneic events may contribute to long-term alterations in autonomic control.

Aging↗
PubMed2003

Frequency of luteinizing hormone pulses in cattle influences duration of persistence of dominant ovarian follicles, follicular fluid concentrations of steroids, and activity of insulin-like growth factor binding proteins.

The objectives of the present study were to determine how varying frequency of LH pulses as controlled by varying treatments with progesterone (P4) in cattle would affect: (1) concentration of steroid hormones and activity of insulin-like growth factor binding proteins (IGFBPs) in the ovarian follicular fluid and blood plasma, and (2) duration of persistence of largest ovarian follicles. There were four treatment groups (n=7 per group) and a control group (n=5) of mature, non-lactating beef cows. Treatments were: (1) two progesterone releasing intravaginal devices (PRIDs) for 16 days (2PRID); (2) a half PRID for 16 days (0.5PRID); (3) two PRIDs for 8 days, then a half PRID for 8 days (2-0.5PRID); or (4) a half PRID for 8 days, then two PRIDs for 8 days (0.5-2PRID). Treatment was initiated on the fifth day of the estrous cycle, which was designated as Day 0, and continued for 16 days. All P4-treated females were administered prostaglandin F2alpha on Day 0 and 1 to regress their corpora lutea. Frequency of LH pulses was greater during treatment with the smaller dose of P4 compared with treatment with the larger dose of P4 and the control group. Ovarian follicles were classified into five categories based on ultrasonographic observations: growing (G); atretic (A); growing dominant (GD); growing persistent (GP); or atretic persistent (AP). At ovariectomy on Day 16, the largest and second largest follicles collected were re-classified into five categories based on follicular concentration of steroids. Classification of the largest follicle collected on Day 16 was influenced by treatment (P<0.005), with the 2PRID group having A follicles, the 2-0.5PRID group GP follicles, the 0.5-2PRID group AP follicles, and the 0.5PRID group GD and GP follicles. Concentrations of 17beta-estradiol (E2) were greatest in GD and GP follicles (P<0.05). There was less (P<0.05) activity of IGFBP-2 in GD follicles and less (P<0.05) activity of IGFBP-3 in GD and GP follicles than other follicles. Activity of IGFBP-4 and -5 was greater (P<0.05) in A and AP follicles than G, GD, and GP follicles. Maintenance of a frequent release of LH pulses over a 16-day period did not result in maintenance of persistent follicles throughout this period indicating that duration of dominance of these follicles is finite even when there is frequent release of LH pulses. Follicular atresia is associated with greater activity of IGFBP-2, -4, -5, and greater concentrations of P4 in follicles, whereas growing dominant and persistent follicles contained greater concentrations of E2, androstenedione (A4), and less IGFBP-2 activity than follicles of other classes. Follicle classifications based on ultrasonography or follicular concentration of steroids did differ (P<0.05) for the largest follicles from the 2PRID group. Two follicles in this group appeared as GD follicles by ultrasonography, but these were atretic based on follicular steroid contents. Objective 1 of the present study yielded the conclusion that concentrations of steroid hormones in follicular fluid and blood plasma could be predictably controlled by regulating the frequency of LH pulses with varying doses of P4. Objective 2 yielded the conclusion that maintain frequent release of LH pulses over a 16-day period could not maintain persistent follicles throughout this period, indicating that duration of dominance of these follicles is finite even when there is frequent release of LH pulses. Follicular atresia in the present study was associated with increased follicular fluid activity of IGFBP-2, -4, -5, and P4, whereas growing dominant and persistent follicles contained greater concentrations of E2, A4, and less IGFBP-2 activity than follicles of other classes.

Administration, Intravaginal↗
PubMed2001

Alterations in potassium channel gene expression in atria of patients with persistent and paroxysmal atrial fibrillation: differential regulation of protein and mRNA levels for K+ channels.

OBJECTIVES: Our purpose was to determine whether patients with persistent atrial fibrillation (AF) and patients with paroxysmal AF show alterations in potassium channel expression. BACKGROUND: Persistent AF is associated with a sustained shortening of the atrial action potential duration and atrial refractory period. Underlying molecular changes have not been studied in humans. We investigated whether a changed gene expression of specific potassium channels is associated with these changes in patients with persistent AF and in patients with paroxysmal AF. METHODS: Right atrial appendages were obtained from 8 patients with paroxysmal AF, 10 with persistent AF and 18 matched controls in sinus rhythm. All controls underwent coronary artery bypass surgery, whereas most AF patients underwent Cox's MAZE surgery (atrial arrhythmia surgery to cure AF) (n = 12). All patients had normal left ventricular function. mRNA (ribonucleic acid) levels were measured by semiquantitative polymerase chain reaction and protein content by Western blotting. RESULTS: mRNA levels of transient outward channel (Kv4.3), acetylcholine-dependent potassium channel (Kir3.4) and ATP-dependent potassium channel (Kir6.2) were reduced in patients with persistent AF (-35%, -47% and -36%, respectively, p < 0.05), whereas only Kv4.3 mRNA level was reduced in patients with paroxysmal AF (-29%, p = 0.03). No changes were found for Kv1.5 and HERG mRNA levels in either group. Protein levels of Kv4.3, Kv1.5 and Kir3.1 were reduced both in patients with persistent AF (-39%, -84% and -47%, respectively, p < 0.05) and in those with paroxysmal AF (-57%, -64%, and -40%, respectively, p < 0.05). CONCLUSIONS: Persistent AF is accompanied by reductions in mRNA and protein levels of several potassium channels. In patients with paroxysmal AF these reductions were observed predominantly at the protein level and not at the mRNA level, suggesting a post-transcriptional regulation.

Aged↗
PubMed2003

Episodic and persistent gun-carrying among urban African-American adolescents.

PURPOSE: To examine whether similar risk factors influenced episodic and persistent gun-carrying among urban African-American adolescents. METHODS: The sample consisted of 705 African-American youths (48.9% male; mean age at baseline = 14.56 years) who were interviewed annually throughout high school as part of a larger study on students who leave school before graduation. Episodic gun-carrying was defined as carrying a gun during one or two waves of the study. Persistent gun-carrying involved carrying a gun during three or four waves. Data were analyzed using multinomial logistic regression to test how risk factors assessed at ninth grade influenced the persistence of gun-carrying. RESULTS: Fifteen percent of students reported carrying a gun episodically, and 5% persistently. "Male gender" (OR = 3.61, 95% CI = 2.16-6.04), "adult weapon-carrying" (OR = 1.58, 95% CI = 1.20-2.09), "marijuana use" (OR = 1.03, 95% CI = 1.01-1.06), "selling drugs" (OR = 3.24, 95% CI = 1.52-6.92), and "fighting" (OR = 1.57, 95% CI = 1.14-2.15) distinguished noncarriers from episodic carriers. Frequency of fighting (OR = 1.60, 95% CI = 1.00-2.57) and selling drugs (OR = 3.29, 95% CI = 1.16-9.35) distinguished episodic gun-carriers from persistent gun-carriers. Variables associated with victimization did not uniquely differentiate among the patterns of gun-carrying. These results were similar for males and females. CONCLUSIONS: Similar risk factors characterize episodic and persistent gun-carrying. Specifically, selling drugs and fighting had a strong dose-response relationship with the persistence of gun-carrying. In this population, episodic gun-carrying should be viewed as very risky and not merely as youthful experimentation or a defensive behavior.

Adolescent↗
PubMed2000

The role of fimbriae and flagella in the colonization, invasion and persistence of Escherichia coli O78:K80 in the day-old-chick model.

To understand the role of flagella and fimbriae of Escherichia coli O78:K80 in avian colibacillosis, day-old chicks were dosed orally with defined afimbriate and or aflagellate mutants and colonization, invasion and persistence compared with that of the wild-type. In an invasion model, chicks were dosed with 1 x 10(5) c.f.u. of a single strain and mutants defective for type 1 fimbriae, curli fimbriae or flagella colonized livers by 24 h although the numbers of bacteria present were significantly less than the wild-type. Mutants colonized between 50 and 75% of spleens whereas the wild-type colonized 100% of spleens. Additionally, the numbers of mutant bacteria in colonized spleens were significantly less than the wild-type. Surprisingly, mutants defective for the elaboration of more than one appendage were no more attenuated than single mutants. In a persistence model, chicks were dosed with 1 x 10(2) c.f.u. of a single strain and mutants defective for type 1 or curli or flagella or any combination thereof persisted as assessed by cloacal swabbing for 5 weeks of the experiment less well than the wild-type. In an additional persistence model, chicks were dosed with 5 x 10(2) c.f.u. of each of wild-type and one mutant together. All mutants were significantly less persistent than the wild-type (P < 0.001) and one mutant which lacked type 1, curli and flagella, was eliminated within 2 weeks. Analysis of the trends of elimination indicated that flagella contributed to persistence more than curli, which contributed more than type 1 fimbriae. Here was evidence for a major role in colonization, invasion and persistence played by type 1, curli and flagella.

Animals↗
PubMed2002

Self-esteem and persistence in the face of failure.

In 2 studies, the authors examined self-esteem, persistence, and rumination in the face of failure. Study 1 manipulated degree of failure and availability of goal alternatives. When an alternative was available, high self-esteem (HSE) participants persisted more than low self-esteem (LSE) participants after a single failure, but less after repeated failure. When no alternative was available, no self-esteem differences in persistence emerged. LSE participants ruminated more than HSE participants. Study 2 examined persistence and rumination for 10 personal goals across an academic year. HSE participants were better calibrated (higher within-subject correlations between perceived progress and persistence across goals), had higher overall levels of persistence, higher grade point averages, and lower levels of rumination than LSE participants. Although traditional views that emphasize the tenacious persistence of HSE individuals need revision, HSE people appear more effective in self-regulating goal-directed behavior.

Achievement↗
PubMed2002

Long-term persistence with antihypertensive drugs in new patients.

The objective of this study was to investigate stay-on-therapy patterns over 3 years among patients prescribed different classes of antihypertensive drugs for the first time. A retrospective analysis of information recorded in the drugs database of the Local Health Unit of Ravenna (Italy) was carried out on 7312 subjects receiving a first prescription for diuretics, beta-blockers, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors or angiotensin II antagonists between 1 January and 31 December 1997. Patients were followed up for 3 years. All prescriptions of antihypertensive drugs filled during the follow-up periods were considered. The patients continuing or discontinuing the initial treatment, the duration of treatment, and the doses taken were all calculated, as well as main factors influencing the persistence rate. The drugs prescribed were predominantly ACE-inhibitors, followed by calcium channel blockers, diuretics, beta-blockers and angiotensin II antagonists. A total of 57.9% of patients continued their initial treatment during the 3-year follow-up period, 34.5% discontinued the treatment, whilst 7.6% were restarted on a treatment in the third year. Persistence with treatment was influenced by: age of patient (persistence rate increasing proportionately with advancing years), type of drug first prescribed (persistence rate higher with angiotensin II antagonists, progressively lower with ACE-inhibitors, beta-blockers, calcium channel blockers and diuretics), gender of patient (persistence was better in males), age of general practitioner (GP) (the younger the GP, the better the persistence rate) and gender of GP (better stay-on-therapy rate with male GP prescribing). In the case of patients treated continuously, mean daily dose increased progressively over the 3 years. With adequate markers, helpful data can be collected from prescription claims databases for the purpose of monitoring the persistence of patients in continuing their medication, and the quality of antihypertensive treatment in a general practice setting.

Antihypertensive Agents↗
PubMed2002

A population-based European cohort study of persistence in newly diagnosed hypertensive patients.

This study assessed the percentage of patients after 1 year who persisted on initially prescribed antihypertensive therapy. Medical records of 2416 patients with newly diagnosed hypertension who were prescribed initial antihypertensive monotherapy by general practitioners in Germany, France, and the United Kingdom were evaluated. Comparisons were made among the angiotensin II receptor antagonist (AIIRA) irbesartan, all other antihypertensive classes (including AIIRAs other than irbesartan), and the AIIRA losartan. Patients initiated on the AIIRA irbesartan scored highest with a persistence rate of 60.8%, followed by patients who received all other AIIRA agents with a persistence rate of 51.3%. Angiotensin-converting enzyme inhibitors, calcium channel blockers, beta-blockers, and losartan were associated with comparable persistence rates, between 42.0% and 49.7%. Patients who received diuretics scored lowest with a persistence rate of 34.4%. Persistence has emerged as an essential factor for blood pressure control. Prescribing an antihypertensive agent that provides a favourable efficacy and tolerability profile may provide greater persistence with therapy and hence a higher level of blood pressure control.

Adrenergic beta-Antagonists↗