Dynamics of ultrashort pulse propagation through fiber gratings

By directly integrating the time-domain coupled-mode equations, we can explicitly obtain and examine the backward and forward propagating waves as a function of position and time within fiber grating structures. We apply this numerical procedure to calculate the temporal reflection and transmission response of fiber gratings subject to ultrashort pulse inputs. This allows us to study the dynamics of the ultrashort pulse-grating interaction.

Use of the 25 mm flanged esophageal Z stent for malignant dysphagia: a prospective multicenter trial

BACKGROUND

An initial multicenter study using a 21 mm flanged esophageal Z stent demonstrated excellent palliation but an 11% immediate complication rate at placement and a 27% migration rate at 1 month. This North American multicenter trial prospectively studied a 25 mm flanged Z stent to define its palliative ability and whether the increased diameter affected placement or migration problems.

METHODS

Fifty patients who had esophageal Z stents at seven university or regional referral hospitals were prospectively studied. Indications for prosthesis placement, previous therapy, patient demographics, incidence of concomitant tracheoesophageal fistula, and degree of dysphagia were defined, as were procedural and subsequent stent-related problems, survival times, the ability to occlude a tracheoesophageal fistula, and subsequent degree of dysphagia.

RESULTS

Twenty-four patients had infiltrating malignancy (16 exophytic and 10 extrinsic), 9 of whom had concomitant tracheoesophageal fistulas. Ten patients (20%) had misplaced stents requiring retrieval and replacement, 12 patients (24%) had subsequent stent-related problems including exsanguination (2), aspiration (3), tumor overgrowth (3), and postplacement migration (4) (8%). There was statistically significant improvement in prestent versus poststent dysphagia and two thirds of patients had complete occlusion of their tracheoesophageal fistula.

CONCLUSIONS

Redesign of the esophageal Z stent has decreased the migration rate without increasing placement or subsequent erosion problems. Its efficacy appears comparable to the currently marketed Z stent for the palliation of malignant dysphagia and occlusion of tracheoesophageal fistula.

A pilot study of nadolol for overt aggression in developmentally delayed individuals

OBJECTIVE

The aim of this preliminary pilot study was to investigate the safety and efficacy of open-label nadolol as an adjunctive pharmacological treatment for aggression and/or inattention/overactivity in a developmentally delayed child, adolescent, and young adult population.

METHOD

Twelve subjects enrolled and completed (mean age 13.8 years, range 9 through 24) a 5-month, open, prospective protocol of nadolol (mean dose 109 mg, range 30 through 220 mg) with systematic baseline and outcome evaluations and weekly clinical assessment.

RESULTS

All subjects were developmentally delayed and most were cognitively delayed. Ten subjects (83%) showed clinical improvement while receiving nadolol. Significant improvements were noted on observer-rated overt categorical aggression, severity of illness, and global impressions of improvement. No significant effects were found for inattention/overactivity. Nadolol was well tolerated, with few side effects.

CONCLUSIONS

Overt categorical aggression presenting in developmentally delayed children, adolescents, and young adults may respond to nadolol treatment.

Physical, psychiatric and social characteristics of the temporomandibular disorder pain dysfunction syndrome: the relationship of mental disorders to presentation

OBJECTIVE

To investigate the physical and psychosocial characteristics and to identify the prevalence of mental disorders in pain dysfunction syndrome (PDS).

DESIGN AND SETTING

New referrals to temporomandibular disorder clinics at Manchester Dental Hospital and diagnosed with PDS.

METHODS

Patients were assessed with a range of socio-demographic, dental and psychosocial measures including a psychiatric interview. Patients with PDS and a mental disorder were compared with those without a mental disorder.

RESULTS

97 patients were included; 32 (33%) had a mental disorder. There were no significant differences between those with and those without a mental disorder on any of the objective dental measures. Those with a mental disorder complained of more pain associated with PDS. They reported more anxiety and depression and also more physical symptoms unrelated to the PDS for which they had sought help and received more treatments.

CONCLUSIONS

Psychosocial factors contribute to the presentation and possibly causation of PDS in the third of patients seen in a hospital setting who have a mental disorder. This factors should be considered when managing patients with PDS.

The SV40 large T-antigen helicase can unwind four stranded DNA structures linked by G-quartets

We describe a novel activity of the SV40 large T-ag helicase, the unwinding of four stranded DNA structures linked by stacked G-quartets, namely stacked groups of four guanine bases bound by Hoogsteen hydrogen bonds. The structures unwound by the helicase were of two types: (i) quadruplexes comprising four parallel strands that were generated by annealing oligonucleotides including clustered G residues in a buffer containing Na+ions. Each parallel quadruplex consisted of four oligonucleotide molecules. (ii) Complexes comprising two parallel and two antiparallel strands that were generated by annealing the above oligonucleotides in a buffer containing K+ions. Each antiparallel complex consisted of two folded oligonucleotide molecules. Unwinding of these unusual DNA structures by the T-ag was monitored by gel electrophoresis. The unwinding process required ATP and at least one single stranded 3'-tail extending beyond the four stranded region. These data indicated that the T-ag first binds the 3'-tail and moves in a 3'-->5'direction, using energy provided by ATP hydrolysis; then it unwinds the four stranded DNA into single strands. This helicase activity may affect processes such as recombination and telomere extension, in which four stranded DNA could play a role.

Management in the Ministry of Health: what are the vital signs?

Effective and efficient management of health services is becoming more and more important in all countries and in all organizations whether profit or non-profit. Management practices and attitudes which may have been accepted in previous years are no longer appropriate. A study was conducted in the Ministry of Health, State of Bahrain to determine the current status of management skills and attitudes. Participants were asked to identify the best and the worst practices of managers. Eight key areas of concern were identified: participative vs. non-participative style, communication, motivation, delegation, human relations skills, style of supervision, goal-oriented behavior, and use of supervisory power. In each of these management-related skill areas, examples of best and worst practices are provided in order to aid the manager/leader in self-assessing his/her abilities as a first step toward improving management.

Prospective multicenter trial of esophageal Z-stent placement for malignant dysphagia and tracheoesophageal fistula

BACKGROUND

Conventional esophageal prosthesis placement has been associated with a 6% to 8% perforation rate and numerous postplacement complications. Expandable esophageal stents have been developed to preclude the above but there are few studies that have prospectively defined clinical results and subsequent stent-related complications.

METHODS

All patients who underwent esophageal Z-stent placement at nine university or referral hospitals were prospectively assessed. Data collected included patient demographics, acute and subacute placement problems, the ability to occlude airway fistulas, prestent and poststent dysphagia scores, and patient survival.

RESULTS

Fifty-four of 56 patients (96%) with refractory dysphagia or malignant esophagoairway fistulae had 73 Z-stents successfully inserted. Initial distal deployment occurred in 13% of the patients and an additional 17% required balloon dilation to achieve maximal diameter. Acute placement complications occurred in 11% of patients and included severe pain (3), bleeding from necrotic tumor (2), and hiatal hernia intussusception (1). No perforations occurred. Eight of 11 patients (73%) had complete tracheoesophageal fistula occlusion and mean dysphagia score (+/- SD) improved from 2.6 (0.7) to 1.1 (1.2) (p < 0.01). Fifteen stents (27%) had delayed migration at a mean of 1 month and 3 required surgery for retrieval. Three patients had ultimate stent erosion resulting in bleeding in 2 (exsanguination 1) or fistula (treated with a conventional stent).

CONCLUSIONS

The authors conclude that esophageal Z-stents can be placed safely and successfully in the majority of patients. The tendency of distal deployment during placement and subsequent migration problems at a time distant from placement in a patient subset deserve attention and are currently being addressed.

Physical symptoms and illness attitudes in adolescents: an epidemiological study

A secondary school population of 805 11-16-year-olds reported lifetime prevalence of 31 physical symptoms and illness attitudes. Girls had a median of six symptoms (range 0-22) and boys five (range 0-22); 67 (8.3%) had 13 or more. Older girls reported more symptoms than younger ones. The excess of symptoms in older girls was related to reporting painful periods rather than simply to age or the menarche. High symptom scorers of both sexes had significantly higher scores on seven Illness Attitude Sub-Scales (Kellner, 1987), with more distress about illness and more treatment experience. The implications of these findings are discussed.

Middle fossa cyst presenting as a delayed complication of temporal lobectomy: case report

Symptomatic middle fossa cysts have not previously been described as complications of temporal lobectomy that has been performed to control complex partial seizures. A patient is described who developed a middle fossa cyst causing mass effect, intracranial hypertension, and neurological deterioration > 2 years after temporal lobectomy for complex partial seizures. An enlarging cyst with cerebrospinal fluid imaging characteristics was detected on neuroimages 1 year before neurological deterioration. The patient was treated by the insertion of a cystoperitoneal shunt for cerebrospinal fluid diversion. The potential causes of an acquired arachnoid cyst and hydrocephalus are discussed.

How developmental supervision and performance management improve effectiveness

Health care supervisors play an important role in helping organizations achieve their goals by ensuring that employees perform their jobs as effectively and efficiently as possible. In most organizations, ill-defined and improperly designed systems exist for assessing and managing employee performance. Health care managers and supervisors can use knowledge of developmental supervision and performance management to increase employee job performance and satisfaction while providing useful information to human resource departments regarding training needs of employees.

Case study: neuroleptic withdrawal dyskinesia exacerbated by ongoing stimulant treatment

Risk factors for neuroleptic withdrawal dyskinesia in children have not been well studied. The authors present a case of a child who had been treated with a combination of neuroleptics and stimulants for nonpsychotic aggressive behavior. A severe withdrawal dyskinesia precipitated by neuroleptic tapering was ameliorated by discontinuation of the psycho-stimulant. Although stimulants have been reported to increase certain involuntary movement disorders, this is the first known report of psychostimulant exacerbation of withdrawal dyskinesia.

Sickle cell anemia, right atrial thrombosis, and the antiphospholipid antibody

We report a patient with sickle cell anemia (homozygous Hb SS) and typical features of sickle chest syndrome but with no response to exchange transfusion. A right atrial thrombus was found, and antiphospholipid antibodies were detected in his blood. He responded to thrombolytic therapy. The relationship between right atrial thrombus and massive pulmonary embolus, and the implications of an additional thrombophilic state in sickle cell disease are discussed.

Isolation and Identification of novel toxins from a new mosquitocidal isolate from Malaysia, Bacillus thuringiensis subsp. jegathesan

A new mosquitocidal Bacillus thuringiensis subsp., jegathesan, has recently been isolated from Malaysia. Parasporal crystal inclusions were purified from this strain and bioassayed against fourth-instar larvae of Culex quinquefasciatus, Aedes aegypti, Aedes togoi, Aedes albopictus, Anopheles maculatus, and Mansonia uniformis. The 50% lethal concentration of crystal inclusions for each species was 0.34, 8.08, 0.34, 17.59, 3.91, and 120 ng/ml, respectively. These values show that parasporal inclusions from this new subspecies have mosquitocidal toxicity comparable to that of inclusions isolated from B. thuringiensis subsp. israelensis. Solubilized and chymotrypsin-activated parasporal inclusions possessed low-level hemolytic activity. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the crystals were composed of polypeptides of 77, 74, 72, 68, 55, 38, 35, 27, and 23 kDa. Analysis by Western blotting (immunoblotting) with polyclonal antisera raised against toxins purified from B. thuringiensis subsp. israelensis reveals that proteins in parasporal inclusions of subsp. jegathesan are distinct, because little cross-reactivity was shown. Analysis of the plasmid content of B. thuringiensis subsp. jegathesan indicates that the genes for toxin production may be located on 105- to 120-kb plasmids. Cry- clones that have been cured of these plasmids are nontoxic. Southern blot analysis of plasmid and chromosomal DNA from subsp. jegathesan showed little or low homology to the genes coding for CryIVA, CryIVB, and CryIVD from B. thuringiensis subsp. israelensis.

Terfenadine pharmacokinetics in breast milk in lactating women

The excretion of terfenadine into breast milk has not been reported previously. Disposition of terfenadine was prospectively studied in four healthy lactating mothers (age, 33 +/- 4 years). Subjects received 60 mg terfenadine every 12 hours over a period of 48 hours to achieve steady-state milk and plasma concentrations. Milk and plasma samples were collected at 1/2, 1, 1 1/2, 2, 3, 4, 6, 8, 12, 24, and 30 hours after the last dose. Terfenadine and its active metabolite milk and plasma concentrations were quantitated by HPLC. Terfenadine was not detected in milk or plasma. Mean +/- SD active metabolite data for milk and plasma are as follows: Cmax (ng/ml), 41.0 +/- 16.4 for milk, 309.0 +/- 120.5 for plasma; tmax (hours), 4.3 +/- 2.4 for milk, 3.9 +/- 3.0 for plasma; t1/2 beta (hours), 14.2 +/- 5.4 for milk, 11.7 +/- 6.4 for plasma; AUC(0-12) (ng.hr/ml) 320.4 +/- 99.8 for milk, 1590.0 +/- 300.4 for plasma. Metabolite milk/plasmaAUC(0-12) ratios ranged from 0.12 to 0.28 (mean, 0.21 +/- 0.07). Newborn dosage estimates based on the highest measured concentration of terfenadine metabolite in milk suggests the maximum level of newborn exposure would not exceed 0.45% of the recommended maternal weight-corrected dose. Estimated amounts consumed by the neonate after the mother is given the recommended dose of the drug are not likely to result in plasma levels producing untoward effects.

Fellowship programs in behavioral neurology

We sent a behavioral neurology fellowship questionnaire to each of the training directors of 160 neurology residency programs throughout the world, seeking information about programs offering advanced training in behavioral neurology (or similar fellowships in cognitive neurology, neurobehavior, or cognitive neuroscience). Response rate was 100%. Thirty-four respondents reported active fellowship programs in behavioral neurology, and 28 additional respondents indicated that a behavioral neurology fellowship was planned. Nine of the 34 programs (26.5%) defined themselves as exclusively or predominantly concerned with dementia and age-related neurobehavioral disorders. Directors of the 34 active fellowship programs estimated that their combined programs had graduated 199 fellows and were currently training fifty. Most fellowships concentrated on outpatient clinical training, with teaching required by 78.1% and research required by 81.8%. Specialty certification for behavioral neurology was favored by over 75% of behavioral neurology fellowship training directors but by only 30% of training directors in residency programs without behavioral neurology fellowships. Behavioral neurology training programs have grown dramatically in response to an increased recognition of the academic interest in and the clinical needs for these services.

Case study: paradoxical response to naltrexone treatment of self-injurious behavior

Opioid receptor antagonists have been studied in the management of self-injurious behavior (SIB) in developmentally disabled individuals. The authors present a case of a severely retarded, autistic man whose SIB increased dramatically during a trial of naltrexone. A paradoxical increase in SIB, attributed to the extinction burst phenomenon during the initial period of nonreward, is known to occur during treatment with naloxone, a short-acting parenteral opioid antagonist. It has only once been reported during treatment with naltrexone, a long-acting orally administered agent. Opioid analgesic effects and learning theory can explain both increases and decreases in SIB after opioid blockade.

CMHC practices related to tardive dyskinesia screening and informed consent for neuroleptic drugs

OBJECTIVE

The authors conducted a national survey of community mental health centers to determine their policies and practices about screening patients for tardive dyskinesia and obtaining informed consent for use of neuroleptic drugs.

METHODS

Clinical directors of 235 centers in the United States, selected by geographic region and population, were surveyed through a nine-item questionnaire.

RESULTS

Although nearly all the 160 respondents reported that they screened patients for tardive dyskinesia, only about two-fifths had formal screening policies, and about two-fifths had screening programs. The Abnormal Involuntary Movement Scale examination was used by almost two-thirds of respondents who screened patients, and about one-fifth relied on unstructured observation. Slightly more than half of respondents specified a frequency for screening examinations, at a modal interval of six months. Seventy percent used nonpsychiatric clinicians for screening. Almost three-quarters of the respondents had informed consent policies for use of neuroleptics. Urban centers tended to be more aware than rural centers of the American Psychiatric Association's tardive dyskinesia screening guidelines. They also used fewer nonmedical practitioners for screening and were more likely to obtain informed consent for neuroleptics.

CONCLUSIONS

Despite the existence of APA guidelines and state policies and regulations about tardive dyskinesia screening, a national effort to educate clinicians about prevention of tardive dyskinesia is still needed.

Psychiatric presentations of epilepsy

The abnormal neuronal excitability underlying seizure disorders may alter behavior. Behavioral alterations associated with epilepsy can occur during the ictal period, especially in patients who suffer partial seizures of temporal or frontal lobe origin, or during the interictal period in the setting of chronic temporolimbic seizure discharges. We use case descriptions to illustrate behavioral presentations of epilepsy that resemble primary psychiatric illnesses, including schizophrenic psychoses, mood disorders, panic disorder, and dissociative disorders. The varied secondary psychiatric syndromes produced by epilepsy are elucidated by a consideration of normal functions of temporal and frontolimbic structures. The clinical pictures provide clues to the causes of primary psychiatric disorders.

The management of chronic somatisation

'Somatisation' is a process in which there is inappropriate focus on physical symptoms and psychosocial problems are denied. In some patients this process becomes chronic (in excess of six months). Special skills and strategies are required by non-psychiatrists to manage these patients, for whom the acceptance of psychiatric treatment should be facilitated. When taking the history, doctors should be aware of psychosocial cues; thereafter they should be consistent and unambiguous in their management. An agenda should be set early on, with limits on investigations. Failure to manage this group of patients is costly, and further intervention studies are required not only to reduce health service and other costs, but also to relieve the non-monetary burden of physical and psychosocial disability on patients and their relatives.