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Johnson MA, Jenkins JM, Bye C. A study of the pharmacokinetic interaction between lamivudine and alpha interferon. Eur J Clin Pharmacol 2000; 56:289-92. [PMID: 10954341 DOI: 10.1007/s002280000148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE This study was designed to investigate any possible pharmacokinetic interaction between lamivudine and alpha interferon as potential candidates for combination therapy for the treatment of hepatitis B virus (HBV). METHODS Nineteen healthy male, Caucasian volunteers, aged 20-41 years and weighing 60.5-83.5 kg completed this open, non-randomised study. They each received a single, abdominal, deep s.c. injection of 10 mIU alpha interferon on day 1, followed by a wash-out period of at least 1 week. Subjects then began a 7-day course of lamivudine (100 mg) followed by a further 10-mIU alpha-interferon injection directly after oral lamivudine dosing. Blood and urine samples were taken pre- and post-dose for alpha-interferon and/or lamivudine assay. RESULTS Lamivudine was safe and well tolerated in all subjects. No adverse events were reported in subjects on lamivudine, whereas 106 adverse events considered attributable to alpha interferon were recorded. Statistical analysis of pharmacokinetic parameters indicated no significant effect of lamivudine on alpha-interferon pharmacokinetics. There was a small statistically significant reduction (approximately 10%) in the area under the lamivudine concentration time curve on co-administration with alpha interferon and a concomitant increase in clearance, which is not considered clinically relevant. CONCLUSIONS Alpha interferon and lamivudine can be co-administered with no requirement for dose modification, as there was no clinically significant difference in the pharmacokinetics of either drug.
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Mathur RS, Akande AV, Keay SD, Hunt LP, Jenkins JM. Distinction between early and late ovarian hyperstimulation syndrome. Fertil Steril 2000; 73:901-7. [PMID: 10785214 DOI: 10.1016/s0015-0282(00)00492-1] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To compare patient and cycle characteristics among three study groups: early ovarian hyperstimulation syndrome (OHSS), late OHSS, and non-OHSS. DESIGN Prospective observational study. SETTING University assisted conception service. PATIENT(S) Women undergoing in vitro fertilization, intracytoplasmic sperm injection or gamete intrafallopian transfer treatment at Bristol University In Vitro Fertilization Service between January 1, 1995, and December 31, 1998. INTERVENTION None. MAIN OUTCOME MEASURE(S) Patient age, prevalence of polycystic ovaries, gonadotropin requirement, peak serum estradiol (E(2)) concentration, number of oocytes retrieved, clinical pregnancy rate, number of gestation sacs, and severity of OHSS. RESULT(S) Women with early OHSS had significantly higher serum E(2) levels and lower gonadotropin requirements than did the other groups. Cycles with either early or late OHSS had significantly more oocytes collected than those without OHSS. Serum E(2) and oocyte numbers did not accurately predict the risk of developing late OHSS. Clinical pregnancies occurred in all cycles with late OHSS, and multiple pregnancies were significantly more frequent in the late OHSS group than in the other groups. Late OHSS was more likely than early OHSS to be severe. CONCLUSION(S) Early OHSS relates to "excessive" preovulatory response to stimulation, whereas late OHSS depends on the occurrence of pregnancy, is likelier to be severe, and is only poorly related to preovulatory events.
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Abstract
In this study, the relationship between short-term emotion expressions and dimensional ratings of internalizing and externalizing symptomatology was examined. Short-term emotions, defined as facial or vocal displays of emotion generally lasting less than 10 seconds and elicited by a specific and proximal event, were observed during recess in 71 children from diverse socioeconomic backgrounds, who were between 4 and 8 years old. Internalizing and externalizing symptomatology was assessed through parent and teacher questionnaire. Sociometric ratings were obtained from peers on children's anger and aggression. It was hypothesized following Tomkins (1979) and others that one affect becomes predominant in the emotional experience of the individual. Different operationalizations of this concept were examined. Using regression analyses, externalizing symptomatology was found to be predicted by higher levels of anger, lower levels of happiness, and lower levels of sadness. Internalizing symptomatology was found to be predicted by higher levels of sadness and lower levels of anger. It was concluded on the basis of these data that the relationship between short-term emotion and internalizing and externalizing psychopathology is best understood as the balance between different short-term emotions. Results are discussed in the context of theories of emotion and their functions.
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Smith MP, Mathur RS, Keay SD, Hall L, Hull MG, Jenkins JM. Periovulatory human oocytes, cumulus cells, and ovarian leukocytes express type 1 but not type 2 11beta-hydroxysteroid dehydrogenase RNA. Fertil Steril 2000; 73:825-30. [PMID: 10731548 DOI: 10.1016/s0015-0282(99)00607-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To further elucidate cortisol metabolism in the follicular microenvironment at the time of oocyte retrieval, the presence of 11beta-hydroxysteroid dehydrogenase (HSD) messenger (m)RNA transcripts in oocytes; cumulus cells; granulosa cells; and CD45(+), CD15(+) leukocytes was assessed semiquantitatively. DESIGN Controlled study using semiquantitative assessment of 11beta-HSD mRNA. SETTING University IVF center. PATIENT(S) Twenty-six patients undergoing controlled ovarian hyperstimulation for assisted conception. INTERVENTION(S) Metaphase II oocytes; cumulus cells; granulosa cells, and CD45(+), CD15(+) leukocytes from individual follicular fluid aspirates. MAIN OUTCOME MEASURES Semiquantitative analysis of PCR products after total RNA extraction and complementary DNA synthesis. RESULT(S) Periovulatory human oocytes; cumulus cells; CD45(+), CD15(+) leukocytes; and granulosa cells consistently express type 1 but not type 2 11beta-HSD mRNA. Expression of mRNA is greatest in cumulus cells. Type 1 11beta-HSD mRNA expression varies considerably in all cell types and among individual follicles and patients. CONCLUSION(S) These studies of mRNA expression suggest that the enzymes present both in and around the periovulatory oocyte will favor a high-cortisol environment.
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Cullinane DC, Jenkins JM, Reddy S, VanNatta T, Eddy VA, Bass JG, Chen A, Schwartz M, Lavin P, Morris JA. Anterior ischemic optic neuropathy: a complication after systemic inflammatory response syndrome. THE JOURNAL OF TRAUMA 2000; 48:381-6; discussion 386-7. [PMID: 10744273 DOI: 10.1097/00005373-200003000-00003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Patients are surviving previously fatal injuries. Unique morbidities are occurring in these survivors. Anterior ischemic optic neuropathy represents a previously unrecognized cause of blindness in the trauma victim. We hypothesize that this phenomenon is caused by unique characteristics of optic edema/ pressure or decreased blood flow associated with massive resuscitation. METHODS Between November of 1991 and August of 1998, there were 18,199 admissions to our trauma center. Of this group, 350 patients required massive volume resuscitation (>20 liters infused over first 24 hours). Patients having closed head injuries, facial fractures or direct orbital trauma were excluded from study. The following variables were studied: demographics, injury severity (Injury Severity Score, highest lactate, worst base deficit, and lowest pH) crystalloid and transfusion requirements, ventilator requirements (PEEP) RESULTS: Of the 350 patients with massive resuscitation, 9 patients were diagnosed with anterior ischemic optic neuropathy (2.6%). Of these, seven patients required celiotomy (78%). Six of the seven celiotomy patients had damage control celiotomies and abdominal compartment syndrome (86%). One patient had a repair of a subclavian artery; one had a complex acetabular repair. Blindness was unilateral in five patients and bilateral in four. All nine patients had evidence of global hypoperfusion, systemic inflammatory response, massive resuscitation, and high ventilatory support; one patient required cardiopulmonary resuscitation. CONCLUSION Prone positioning is known to be associated with an increased intraocular pressure. We postulate that the combination of massive resuscitation and prone positioning will increase the incidence of anterior ischemic optic neuropathy. As such, we recommend that prone positioning for adult respiratory distress syndrome be reserved for only those patients at risk of death.
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Jenkins JM, Buccioni JM. Children's understanding of martial conflict and the marital relationship. J Child Psychol Psychiatry 2000; 41:161-8. [PMID: 10750542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Children's understanding of marital conflict and the marital relationship was investigated in 60 children of 5, 7, and 9 years old. Age differences were hypothesized in four areas of children's understanding of marital conflict and the marital relationship, based on the development between 5 and 9 years of age of children's abilities to (a) analyse complex sequences of behavior in terms of the mental states of protagonists and (b) integrate multiple social roles. The four areas investigated were: conceptions of marital conflict, conflict resolution, family triangulation, and integration of the spousal and parental roles. Children were read stories involving family interactions. Open-ended questions were asked about their understanding of these interactions and a coding scheme was devised that reflected theoretical concepts. Nine-year-olds differed from 5-year-olds on all aspects of their understanding of marital conflict and the marital relationship, and 7-year-olds showed levels of understanding between 5- and 9-year-olds. Younger children were less likely than older children to explain marital conflict in terms of the divergent goals of each parent, to understand conflict resolution as dependent on one person changing their beliefs or goals, to understand that parents were simultaneously spouses and parents and to understand the nature of triangulation. Marital conflict is interpreted very differently by children of different ages.
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Liversedge NH, Turner A, Horner PJ, Keay SD, Jenkins JM, Hull MG. The influence of bacterial vaginosis on in-vitro fertilization and embryo implantation during assisted reproduction treatment. Hum Reprod 1999; 14:2411-5. [PMID: 10469722 DOI: 10.1093/humrep/14.9.2411] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
There is growing evidence that the pathogenic effects of bacterial vaginosis may not be confined to the lower genital tract. Possible associations with infertility and effects on fertilization and implantation were studied in patients undergoing in-vitro fertilization (IVF) treatment. High vaginal swabs taken at the time of oocyte collection were assessed by Gram staining. The prevalence of bacterial vaginosis and of intermediate and normal flora in 301 patients was 25.6, 14.0 and 60.4% respectively. Bacterial vaginosis was more prevalent in patients with tubal (31.5%, n = 149) compared with non-tubal (19.7%, n = 152) infertility (odds ratio (OR) 1.87, CI 1.11-3.18, P = 0.02). Bacterial vaginosis did not have an adverse effect on fertilization rate. Further, no significant difference in implantation rates was seen when comparing bacterial vaginosis (15. 8%, OR 1.03, CI 0.66-1.61) and intermediate flora (13.1%, OR 0.82, CI 0.45-1.52) with normal flora (15.5%). Though confidence intervals around the observations were relatively wide, the findings suggest that routine screening for bacterial vaginosis in the hope of improving the success of IVF treatment is not justified. The prevention of complications in pregnancy associated with bacterial vaginosis might be a more relevant indication for screening at the time of IVF treatment, in particular patients with tubal disease, if treatment were shown to be effective for that particular purpose. However, antibiotic treatment before IVF has been shown to be positively disadvantageous for IVF by encouraging other organisms.
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Astington JW, Jenkins JM. A longitudinal study of the relation between language and theory-of-mind development. Dev Psychol 1999; 35:1311-20. [PMID: 10493656 DOI: 10.1037/0012-1649.35.5.1311] [Citation(s) in RCA: 492] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fifty-nine 3-year-olds were tested 3 times over a period of 7 months in order to assess the contribution of theory of mind to language development and of language to theory-of-mind development (including the independent contributions of syntax and semantics). Language competence was assessed with a standardized measure of reception and production of syntax and semantics (the Test of Early Language Development). Theory of mind was assessed with false-belief tasks and appearance-reality tasks. Earlier language abilities predicted later theory-of-mind test performance (controlling for earlier theory of mind), but earlier theory of mind did not predict later language test performance (controlling for earlier language). These findings are consistent with the argument that language is fundamental to theory-of-mind development.
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Mathur RS, Jenkins JM. Severe OHSS: patients should be allowed to weigh the morbidity of OHSS against the benefits of parenthood. Hum Reprod 1999; 14:2183-5. [PMID: 10469677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
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Abstract
BACKGROUND In 1993 more than 1 million Swiss residents traveled to a tropical or subtropical country. Although most pretravel advice is given by general practitioners, a number of travelers also seek advice from pharmacists. Little is known about the quantity and quality of travel advice given or the sources of information used by this group. METHODS One-hundred and twenty randomly selected pharmacists from three Swiss cantons were first interviewed in a cross-sectional study on the telephone. All study participants subsequently received a pretested questionnaire, in which most of the questions asked on the phone were repeated, with additional questions regarding the sources of information used for travel advice and the cooperation of general practitioners. Included in both parts of the study were two scenarios of fictive travelers seeking health advice for destinations frequently visited by Swiss tourists (Thailand and Kenya). RESULTS Of 136 pharmacists approached, all who said they sometimes gave travel advice, agreed to participate (88%). Fifty-six percent of them give travel advice regularly (mean 2-3 times per month). General knowledge on the main health hazards was good, but for treatment of travelers' diarrhea, only 59% spontaneously mentioned the need for increased fluid intake, whereas 100 % recommended antidiarrheal drugs. Protection from the sun was mentioned only by 10 % of the respondents, and only 8 % said that the traveler should seek advice from a medical doctor. Over 95% could name the three most important measures against mosquito bites, although up to 20% still recommend Vitamin B1 as well. On the telephone, only 19% (for Thailand) and 31% (for Kenya) gave accurate advice on malaria protection, and 13% (for Thailand) and 3% (for Kenya) could make correct recommendations about vaccination. However, more than 50% said that in practice they would consult documentation before giving any advice, with the Bulletin of the Federal Office of Health (BFOH) being the most commonly used source of information. In the questionnaire interview, where documentation was used, the accuracy of advice increased, especially for malaria protection (74% correct for Thailand and 93% for Kenya). CONCLUSIONS The overall knowledge of Swiss pharmacists on travel medicine issues is satisfactory. Specific questions need further attention, such as treatment of travelers' diarrhea, sun protection and advice on malaria prophylaxis and vaccinations. For the latter two, clients should also consult a medical doctor. Collaboration between doctors and pharmacists, and the consistency of the advice given, are important in improving compliance. Reliable information sources are available in pharmacies and are used.
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Thompson JA, Jenkins JM. Ventriculoatrial conduction metrics for classification of ventricular tachycardia with 1:1 retrograde conduction in dual-chamber sensing implantable cardioverter defibrillators. J Electrocardiol 1999; 31 Suppl:152-6. [PMID: 9988021 DOI: 10.1016/s0022-0736(98)90309-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The introduction of dual-chamber sensing in implantable cardioverter defibrillators (ICDs) has greatly reduced the incidence of false detection due to supraventricular tachycardias. The remaining arrhythmias which serve to confound classification are supraventricular tachycardias (SVTs) with 1:1 anterograde conduction and ventricular tachycardias (VT) with 1:1 retrograde conduction. An algorithm has been designed and tested (28 patients) which employs ventriculoatrial (VA) conduction measurements to separate 1:1 VTs from 1:1 SVTs. A study was conducted to assess realistic VA interval boundaries for classification of arrhythmias with 1:1 retrograde atrial conduction. Intracardiac atrial and ventricular recordings of 7 passages of VT with retrograde conduction, 12 passages of atrioventricular nodal reentrant tachycardia (AVNRT), 3 passages of atrial tachycardia (AT), 8 passages of sinus tachycardia (ST), and 2 passages of orthodromic reentrant tachycardia (ORT) were analyzed. Automated real-time atrial and ventricular waveform recognition was performed on each passage and VA intervals were measured. Separation of VT with retrograde conduction from other 1:1 supraventricular tachycardias was effected by imposing discrete VA interval boundaries. VA boundaries of 80 ms to 234 ms classified 1:1 VT with 100% sensitivity (SENS) and 80% specificity (SPEC). In addition, the lower boundary completely classified AVNRT with 100% SENS and 100% SPEC, and all passages of ST were contained above the upper boundary. These findings could be of importance in algorithms for next-generation implantable cardioverter defibrillators which include two-chamber (atrial and ventricular) sensing and two-chamber interval measurements.
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Keay SD, Barlow R, Eley A, Masson GM, Anthony FW, Jenkins JM. The relation between immunoglobulin G antibodies to Chlamydia trachomatis and poor ovarian response to gonadotropin stimulation before in vitro fertilization. Fertil Steril 1998; 70:214-8. [PMID: 9696209 DOI: 10.1016/s0015-0282(98)00145-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To determine whether a relation exists between previous exposure to Chlamydia trachomatis and impaired ovarian response to gonadotropin stimulation. DESIGN Controlled clinical study. SETTING Two university IVF centers. PATIENT(S) Two hundred forty-two patients receiving IVF treatment and 81 control patients. Ninety-four patients with a poor response to IVF, defined by cycle cancellation in response to a daily stimulation dose of 300 IU of FSH, and 148 patients with a good response were matched for age. Twenty-eight pregnant controls and 53 controls of proven fertility also were included. INTERVENTION(S) Serum samples were obtained from patients and controls. Serum levels of immunoglobulin (Ig) G antibodies to C. trachomatis were determined by ELISA. MAIN OUTCOME MEASURE(S) The prevalence of serum IgG antibodies to C. trachomatis in critically defined poor responders was compared with that of age-matched good responders. RESULT(S) A significantly higher proportion of poor responders had serum IgG antibodies to C. trachomatis compared with good responders (44.7% and 30.4%, respectively). Patients undergoing IVF had a significantly higher prevalence of IgG antibodies to C. trachomatis (36%) than did either pregnant or nonpregnant controls (12%). CONCLUSION(S) A significantly higher prevalence of serum IgG antibodies to C. trachomatis was observed in critically defined poor responders, suggesting a possible detrimental effect of C. trachomatis on subsequent ovarian function.
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Cass AS, Grine WB, Jenkins JM, Jordan WR, Mobley TB, Myers DA. The incidence of lower-pole nephrolithiasis--increasing or not? BRITISH JOURNAL OF UROLOGY 1998; 82:12-5. [PMID: 9698656 DOI: 10.1046/j.1464-410x.1998.00684.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine if the incidence of lower-pole nephrolithiasis is increasing. METHODS A previously published meta-analysis of trends in the location of stones in the kidney, using data from 1984 to 1992, determined the percentage of lower pole stones in 26,722 kidney stones treated by extracorporeal shockwave lithotripsy (ESWL). We performed prospective studies on all patients treated by ESWL for a single renal stone (not manipulated from the ureter) in two organizations: at Lithotripters Inc., 47,303 stones were treated with ESWL by 1000 urologists in private practice from 1989 to 1995. At the Midwest Urologic Stone Unit, 9357 stones were treated with ESWL by 200 urologists in private practice from 1987 to 1995. The distribution of stones in both samples was compared with that reported earlier. RESULTS The meta-analysis for stone location trends from the previously published article suggested that the percentage of kidney stones in the lower pole at ESWL increased erratically from 1984 to 1989 but was then stable for 3 years. The Lithotripters Inc. sample showed an essentially constant incidence from 28% in 1990 to 30% in 1995, and the Midwest Urologic Stone Unit sample showed an essentially constant incidence from 35% in 1988 to 36% in 1995. CONCLUSION The incidence of lower pole nephrolithiasis has remained stable from 1990.
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Van Natta TL, Morris JA, Eddy VA, Nunn CR, Rutherford EJ, Neuzil D, Jenkins JM, Bass JG. Elective bedside surgery in critically injured patients is safe and cost-effective. Ann Surg 1998; 227:618-24; discussion 624-6. [PMID: 9605653 PMCID: PMC1191333 DOI: 10.1097/00000658-199805000-00002] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The success of elective minimally invasive surgery suggested that this concept could be adapted to the intensive care unit. We hypothesized that minimally invasive surgery could be done safely and cost-effectively at the bedside in critically injured patients. SUMMARY BACKGROUND DATA This case series, conducted between October 1991 and June 1997 at a Level I trauma center, examined bedside dilatational tracheostomy (BDT), percutaneous endoscopic gastrostomy (PEG), and inferior vena cava (IVC) filter placement. All procedures had been performed in the operating room (OR) before initiation of this study. METHODS All BDTs and PEGs were performed with intravenous general anesthesia (fentanyl, diazepam, and pancuronium) administered by the surgical team. IVC filters were placed using local anesthesia and conscious sedation. BDTs were done using a Ciaglia set, PEGs were done using a 20 Fr Flexiflow Inverta-PEG kit, and IVC filters were placed percutaneously under ultrasound guidance. Cost difference (delta cost) was defined as the difference in hospital cost and physician charges incurred in the OR as compared to the bedside. RESULTS Of 16,417 trauma admissions, 379 patients (2%) underwent 472 minimally invasive procedures (272 BDTs, 129 PEGs, 71 IVC filters). There were four major complications (0.8%). Two patients had loss of airway requiring reintubation. Two patients had an intraperitoneal leak from the gastrostomy requiring operative repair. No patient had a major complication after IVC filter placement. Total delta cost was $611,994. When examined independently, the cost was $324,224 for BDT, $164,088 for PEG, and $123,682 for IVC filter. OR use was reduced by 506 hours. CONCLUSIONS These bedside procedures have minimal complications, eliminate the risk associated with patient transport, reduce cost, improve OR utilization, and should be considered for routine use in the general surgery population.
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Jenkins JM, Pelowitz DG, Jenkins RE. A testing system for implantable cardioverter defibrillators. J Electrocardiol 1998; 30 Suppl:126-9. [PMID: 9535489 DOI: 10.1016/s0022-0736(98)80058-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Implantable cardioverter defibrillator (ICD) testing during the implantation process is important in order to avoid repeated induction of arrhythmias, which extends the implantation procedure and poses a risk to the patient. Hence, an in vitro testing system has been designed to assist optimal device programming and avoid repetitive inductions. The system includes a high-speed computer with A/D and D/A subsystems. Software has been designed to eliminate repeated arrhythmia induction by real-time capture and storage of the electrogram. Subsequently, the electrogram can be replayed into ICD software simulators at a variety of settings to determine candidate programming parameters. To validate the simulation system, signals were fed directly to an ICD via an attenuator. Output event markers were captured simultaneously with the signal into a digital file to assess the device performance. Four ventricular tachycardia (VT), three supraventricular tachycardia, (SVT), three atrial flutter (AFL), three atrial fibrillation (AF), and ten ventricular fibrillation (VF) passages were used to verify the system. Test settings were 110-160 beats/min for detection rate and 5 seconds for shock delay. The simulator and ICD detected the episodes for all passages at the 110 beats/min setting. For the setting of 160 beats/min, two VTs, two SVTs, three AFLs, and nine VFs were detected by the device, but no Afb triggered a shock. The simulator detection criteria were met by two VTs, two SVTs, three AFLs, ten VFs, and one AF. The mean detection time was 6,869-7,330 ms (110-160 beats/min) for the simulator and 7,840-8,170 ms for device. Comparison of results showed general agreement between simulator and device. Results demonstrated that device behavior at a variety of settings can be elucidated by the simulator for selection of optimal performance. The automated system can also function as a test bed for evaluation of new algorithms during device development and design.
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Caswell SA, Jenkins JM, DiCarlo LA. Comprehensive scheme for detection of ventricular fibrillation for implantable cardioverter defibrillators. J Electrocardiol 1998; 30 Suppl:131-6. [PMID: 9535490 DOI: 10.1016/s0022-0736(98)80060-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Implantable cardioverter defibrillators (ICDs) detect and defibrillate ventricular fibrillation (VF) and ventricular tachycardia (VT). Other therapies which use less energy are also available to terminate VT. Previous studies have shown that ICD rate schemes often misdiagnose VT as VF. In this study, an improved VF classification scheme was designed and tested, which employs the classic rate criteria plus paired signal concordance (PSC); PSC uniquely detects VF where VT and VF rates overlap (220-340 ms). Two signals from a bipolar pair (1 cm) recorded in a unipolar sense exhibit similar signal shape for concordant rhythms, such as sinus rhythm and VT, and disconcordance for VF. Once the rate criterion is met, PSC is measured by the peak normalized cross-correlation coefficient calculated over the depolarization. Variability, measured by a modified range, determined the contextual diagnosis over a passage. Sinus rhythm (20), VT (12), VF (22), atrial fibrillation (10), sinus rhythm with ventricular premature depolarizations (7), and polymorphic VT (4) passages were recorded from 38 patients. Rate-PSC was tested with unfiltered, digitized signals (1-500 Hz, 1,000 samples per second) and with filtered, downsampled signals (1-50 Hz, 100 samples per second). Sensitivity values, or percentage of correct VF detection, and specificity values, or detection of all other rhythms, were generated and compared with simulations of three commercial ICDs programmed to similar settings as rate-PSC and to nominal settings. The sensitivity values for rate-PSC with unfiltered and with filtered signals and for ICDs with 220 ms and with nominal settings were 100%, 100%, 48-80%, and 100%, respectively; the corresponding specificity values were 95%, 83%, 93%, and 7-13%, respectively. It was concluded that the rate-PSC scheme was able to reliably separate VF from other rhythms, even rhythms that have a variable morphology or variable rate. With the confidence of accurate VF detection, use of low-energy therapies for non-VF rhythms will increase device longevity and enhance patient comfort.
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Douglas SP, Jenkins JM, Kadler KE. Collagen IX: evidence for a structural association between NC4 domains in cartilage and a novel cleavage site in the alpha 1(IX) chain. Matrix Biol 1998; 16:497-505. [PMID: 9550266 DOI: 10.1016/s0945-053x(98)90020-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Collagen IX, a structural component of the extracellular matrix of connective tissues, is synthesized as long and short forms which contain or lack, respectively, a 27 kDa non-collagenous (NC) 4 domain at the N-terminus of the alpha 1(IX) chain of the molecule. The long form occurs in cartilage and developing cornea, but not in vitreous, suggesting a specialized function for the NC4 domain, perhaps by interacting with other macromolecules. To test this hypothesis, embryonic chick cartilage was treated with DTSSP, dissociated with bacterial collagenase, and the NC4-containing DTSSP-cross-linked protein complexes examined and purified. Analysis of cartilage extracts using an anti-NC4 antibody, and of purified NC4-containing complexes, identified a predominant NC4 dimer. A naturally-occurring N-terminal fragment of the alpha 1(IX) chain, whose size is equivalent to the NC4-COL3-NC3 domains of the chain, was identified. Association of collagen IX molecules via NC4 domains and the existence of a cleavage site close to the NC3 domain of the molecule are likely to be of primary importance in the growth and remodeling processes of cartilage, in health and disease.
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Keay SD, Liversedge NH, Jenkins JM. Could ovarian infection impair ovarian response to gonadotrophin stimulation? BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1998; 105:252-3. [PMID: 9532982 DOI: 10.1111/j.1471-0528.1998.tb10082.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Mathur RS, Jenkins JM, Bansal AS. The possible role of the immune system in the aetiopathogenesis of ovarian hyperstimulation syndrome. Hum Reprod 1997; 12:2629-34. [PMID: 9455826 DOI: 10.1093/humrep/12.12.2629] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
This review examines recent evidence suggesting a role for the immune system, in particular cytokines, in the pathogenesis of ovarian hyperstimulation syndrome (OHSS). Ovarian tissue is known to contain cells capable of producing a range of immunological mediators and the concentrations of these have been shown to be elevated in serum and ascitic fluid from women with established OHSS. Available evidence points to a role for vascular endothelial growth factor and interleukin-2, possibly acting through other intermediary cytokines, in the pathogenesis of OHSS. However, each individual has a unique cytokine profile and several cytokines may share biological actions, making it difficult to interpret data on isolated cytokine concentrations from relatively small numbers of patients. Improved understanding of the role of the immune system in the development of OHSS may have implications for the prediction, prevention and management of this iatrogenic condition.
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Stevenson SA, Jenkins JM, DiCarlo LA. Analysis of the intraventricular electrogram for differentiation of distinct monomorphic ventricular arrhythmias. Pacing Clin Electrophysiol 1997; 20:2730-8. [PMID: 9392803 DOI: 10.1111/j.1540-8159.1997.tb05430.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study investigated the effectiveness of correlation waveform analysis for identifying different ventricular electrogram morphologies of multiple VTs in the same patient. Patients with implantable antitachycardia devices are commonly subject to the occurrence of more than one distinct monomorphic VT. Each of these VTs may have unique therapeutic alternatives for termination. VTs with identical and different monomorphic configurations were recorded (1-500 Hz) using distal bipolar (1 cm) and distal unipolar electrograms from the right ventricular apex. Thirty-six distinct monomorphic VTs induced in 15 patients were analyzed. Nine VTs with identical morphologies (12/12 surface ECGs) were induced twice and used as a control. A template was created for each VT induced. Correlation waveform analysis was used to compare each depolarization of all other VTs induced subsequently in the same patient. The mean correlation coefficient (p mu) of cycle-by-cycle analysis was used as a discriminant function: p mu > or = 0.95 was considered matched; and p mu < 0.95 was considered distinct. From the control population, VTs were successfully classified as identical in 9 of 9 cases (100%) using both bipolar and unipolar electrograms. VTs with different monomorphic configurations were successfully classified as being different in 31 of 33 cases (94%) using bipolar electrogram analysis and in 29 of 33 cases (88%) using the unipolar. Template matching is effective for detecting: (1) the recurrence of VTs, which are identical; and (2) the occurrence of a VT with a different configuration. This method appears effective using either unipolar or bipolar intracardiac waveforms.
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Nunn CR, Neuzil D, Naslund T, Bass JG, Jenkins JM, Pierce R, Morris JA. Cost-effective method for bedside insertion of vena caval filters in trauma patients. THE JOURNAL OF TRAUMA 1997; 43:752-8. [PMID: 9390485 DOI: 10.1097/00005373-199711000-00004] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The need for patient transport for inferior vena cava (IVC) filter placement impacts patient safety, comfort, charges, and nursing care. Bedside, ultrasound-guided IVC filter placement may offer an acceptable, cost-effective alternative. METHODS Prospective cohort study of 55 consecutive trauma patients requiring IVC filter placement. During a 13-month period (August of 1995-September of 1996), patients meeting criteria for IVC filter were evaluated. Complications were recorded, and the potential financial savings were determined. RESULTS Of 3,172 trauma admissions, 55 patients met IVC filter criteria and 49 patients had IVC filters placed under ultrasound guidance. In six patients (10.9%), ultrasound guided filter placement failed. There were four complications in four patients (8.2%). Over 13 months, charges were reduced by $69,800 when compared with radiology suite placement and $118,300 when compared with operative placement. CONCLUSIONS Ultrasound guided, bedside placement of IVC filters is a safe, cost-effective method of pulmonary embolism prophylaxis in select trauma patients.
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Smith MP, Keay SD, Hall L, Harlow CR, Jenkins JM. The detection and confirmation of 11 beta-hydroxysteroid dehydrogenase type 1 transcripts in human luteinized granulosa cells using RT-PCR and plasmid pUC18. Mol Hum Reprod 1997; 3:651-4. [PMID: 9294847 DOI: 10.1093/molehr/3.8.651] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The activity of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) in human granulosa cells has been shown to be associated with the outcome of treatment following in-vitro fertilization and embryo transfer. There are two known isoforms of 11 beta-HSD which differ significantly in their actions and co-factor requirements. The net activity of 11 beta-HSD which differ significantly in their actions and co-factor requirements. The net activity of 11 beta-HSD within the human ovary is unclear, but may be of particular importance within the ovarian follicle in regulating possible glucocorticoid influences on the oocyte. This study presents preliminary information regarding establishment of techniques to identify transcripts of the 11 beta-HSD isoforms within human granulosa cells and human cumulus cells using reverse transcription-polymerase chain reaction. In view of the high expression of the type 1 11 beta-HSD isoform and the possibility of other 11 beta-HSD isoforms in the ovary, plasmid technology was used to confirm the technique specifically identifying the known isoforms.
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Harlow CR, Jenkins JM, Winston RM. Increased follicular fluid total and free cortisol levels during the luteinizing hormone surge. Fertil Steril 1997; 68:48-53. [PMID: 9207583 DOI: 10.1016/s0015-0282(97)81474-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To determine the changes in follicular fluid (FF) total and free cortisol during the LH surge in naturally ovulating women. PATIENT(S) Twenty-six women having diagnostic laparoscopy during the follicular phase of normal menstrual cycles were selected. INTERVENTION(S) Blood samples were collected 1 day before, the day of, and 1 day after surgery and the results of serum E2 and LH were used to divide the cycles retrospectively into pre- and post-LH surge groups. Follicular fluid was collected during laparoscopy. MAIN OUTCOME MEASURE(S) Serum P, total and free cortisol, and FF volume, E2, P, total cortisol, and free cortisol were measured on the day of surgery. RESULT(S) Median serum and FF P levels were significantly higher in the post-LH surge group compared with the pre-LH surge group (0.54 versus 1.54 ng/mL [1.7 versus 4.85 nmol/L] and 5.03 versus 28.0 micrograms/mL [15.8 versus 88.0 mumol/L], respectively). Follicular fluid volume also increased significantly after the surge (2.5 versus 4.5 mL). Median serum total and free and percent free cortisol were higher after the surge, although not significantly. In contrast, FF total, free, and percent free levels increased dramatically between pre- and post-LH surge samples (4.41 versus 43.6 ng/mL [16.0 versus 158 nmol/L], 0.138 versus 6.68 ng/mL [0.5 versus 24.2 nmol/L], and 3.3% versus 15.0%, respectively; P < 0.05). CONCLUSION(S) An increase in total and free cortisol occurs in the follicle during the LH surge. Cortisol and its regulation by 11 beta-hydroxysteroid dehydrogenase therefore may exert a physiologic role in oocyte maturation or ovulation.
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Keay SD, Liversedge NH, Mathur RS, Jenkins JM. Assisted conception following poor ovarian response to gonadotrophin stimulation. BRITISH JOURNAL OF OBSTETRICS AND GYNAECOLOGY 1997; 104:521-7. [PMID: 9166190 DOI: 10.1111/j.1471-0528.1997.tb11525.x] [Citation(s) in RCA: 191] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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