Validity and reliability of the Group for Learning Useful and Performant Swallowing (GLUPS) tool

INTRODUCTION

To validate the Group for Learning Useful and Performant Swallowing (GLUPS), a clinical tool dedicated to videofluoroscopy swallowing study (VFSS).

METHODS

Forty-five individuals were recruited from January 2022 to March 2023 from the Department of Otolaryngology Head and Neck Surgery of University Hospital Saint-Pierre (Brussels, Belgium). Subjects underwent VFSS, which was rated with GLUPS tool by two blinded otolaryngologists and one speech-therapist. VFSS were rated twice with GLUPS within a 7-day period to assess test-retest reliability.

RESULTS

Twenty-four patients and twenty-one controls completed the evaluations. The internal consistency (α = 0.745) and the test-retest reliability (rs = 0.941; p = 0.001) were adequate. GLUPS reported a high external validity regarding the significant correlation with the Penetration-Aspiration Scale (rs = 0.551; p = 0.001). Internal validity was adequate, because GLUPS score was significant higher in patients compared to controls (6.21 ± 4.42 versus 2.09 ± 2.00; p = 0.001). Interrater reliability did not report significant differences in the GLUPS sub- and total score among the independent judges. The mean GLUPS score of individuals without any evidence of VFSS abnormalities was 2.09/23 (95% CI  1.23-2.95), which supported that a GLUPS score ≥ 3.0 is suggestive of pathological VFSS.

CONCLUSIONS

GLUPS is a clinical instrument documenting the abnormal findings of oral and pharyngeal phases at the VFSS. GLUPS demonstrated high reliability and excellent criterion-based validity. GLUPS may be used in clinical practice for the swallowing evaluation at the VFSS.

Impact of skin-to-skin contact on the autonomic nervous system in the preterm infant and his mother

Before, during and after mother-newborn skin-to-skin contact (SSC), parasympathetic activity was evaluated by heart rate variability (HRV) analysis. SSC had a favorable impact on maternal and premature infant parasympathetic activities with a more pronounced response for neonates when the basal HRV values were lower, without modifications of EDIN scores, temperatures or oxygen saturation.

The first preclinical pharmacotoxicological safety assessment of CGS 35601, a triple vasopeptidase inhibitor, in chronically instrumented, conscious, and unrestrained spontaneously hypertensive rats

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme-1 with respective IC50 values of 22, 2, and 55 nM. We characterized the safety profile and toxicity of escalating doses of CGS 35601 over a 20-day period in chronically instrumented, unrestrained, conscious, male, spontaneously hypertensive rats (SHR). Once instrumented with an arterial catheter, the SHR were placed in metabolic cages allowing daily assessment of hemodynamics and blood sampling for biochemical and hematological measurements. After a 7-day stabilization period, the SHR were divided into 2 groups: Gr. 1, (n = 13 to 18) receiving CGS 35601 at 0.01, 0.1, 1 and 5 mg kg(-1) day(-1) (continuous i.a. infusion) for 5 consecutive days/dose, followed by a 5-day washout; and Gr. 2, (n = 10) receiving vehicle (saline). The highest dose of CGS 35601 dose-dependently reduced MABP from 156 +/- 4 up to 94 +/- 5 mm Hg, whereas heart rate, metabolic, electrolytic, and hematological profiles, growth, diuresis, and renal activity were unaffected, and no hepatic or liver toxicities were observed. These results suggest that this novel triple VPI presents no safety concerns at this stage and may become of interest for the treatment of hypertension and other cardiovascular disorders. Long-term chronic experiments are needed to assess possible angioedema and increases in vascular permeability.

Triple VPI CGS 35601 reduces high blood pressure in low-renin, high-salt Dahl salt-sensitive rats

We previously reported that CGS 35601, a potent triple inhibitor of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme 1, completely normalized mean arterial blood pressure (MABP) in 36-week-old spontaneously hypertensive rats, a normal renin model. The aim of the present study was to determine the effects of this triple vasopeptidase inhibitor (VPI) on the hemodynamic profile of instrumented, conscious, and unrestrained Dahl salt-sensitive (DSS) rats, a gene-prone, high-salt diet-induced low-renin hypertension model. Male DSS rats (mean weight [+/-SEM], 385 +/- 10 g) were fed a normal diet (Group 1) or a high-salt diet (Groups 2 and 3; 8% NaCl in food) for 6 weeks and then instrumented with a carotid catheter and placed individually in metabolic cages for 30 days. The hemodynamic, hematological, and biochemical profiles were assessed daily. Dose-dependent treatment started after a 7-day stabilization period in Groups 1 and 2 (vehicle dosage, 250 microl/hr) and Group 3 (CGS 35601 dosages of 0.1, 1, and 5 mg/kg/day for 6 days per dose by means of constant intra-arterial infusion), followed by a 5-day washout period. Two additional groups included normotensive Wistar rats (Group 4) and DSS rats that received a double high-salt solid (8% NaCl) and liquid (1% NaCl) diet (Group 5). The MABP in rats receiving CGS 35601 decreased in a dose-dependent fashion toward the baseline level observed in DSS rats receiving a normal diet. The heart rate was unaffected. The hemodynamic profile returned to normal during the washout period. This novel triple VPI is a potent and effective antihypertensive agent with a safe short-term profile that may be of interest for treating hypertension and other cardiovascular diseases. Other hypertensive rat models are being tested.

The hemodynamic and metabolic profiles of Zucker diabetic fatty rats treated with a single molecule triple vasopeptidase inhibitor, CGS 35601

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin converting enzyme (ACE), neutral endopeptidase (NEP), and endothelin (ET) converting enzyme-1 (ECE-1), with respective IC(50) values of 22, 2, and 55 nM. The aim of the present study was to establish the hemodynamic profile of Zucker diabetic fatty (Zdf)-Fatty rats, a high-fat diet gene-prone model developing spontaneous Type 2 diabetes (T2D) and the effects of CGS 35601. Male Zdf-Fatty (14 weeks, n = 17-23), Zdf-Lean (14 weeks, n = 8-10), and Wistar (14 weeks, n = 9-10) rats on distinct diets were implanted with a catheter in the left carotid and placed individually in a metabolic cage for 30 days. The hemodynamic profile and some metabolic biomarkers were assessed daily. After a 7-day stabilization period, the Zdf-Fatty rats were divided into two groups: Group 1, controls (n = 7-10) receiving vehicle-saline (250 microl/hr) and Group 2, (n = 10-13) receiving increasing doses of CGS 35601 (0.1, 1, and 5 mg/kg/day x 6 days each, intra-arterially) followed by a 5-day washout period. Mean arterial blood pressure (MABP) of young Zdf-Fatty rats was compared with age-matched Zdf-Lean and Wistar rats, which were found similar. MABP decreased by 5.9% (from baseline at 102 +/- 5 to 96 +/- 4 mmHg), 12.7% (to 89 +/- 6 mmHg) and 21.6% (to 80 +/- 4 mmHg), at 0.1, 1, and 5 mg/kg/day, respectively, in CGS 35601-treated Zdf-Fatty rats. Systolic and diastolic blood pressures were similarly reduced. The heart rate was not affected. Hyperglycemic status and insulin-resistance were not modulated by short-term treatment. CGS 35601 presented an excellent short-term safety profile. This novel molecule and class of VPI may be of interest for lowering vascular tone. Further long-term studies, once cardiovascular and renal complications have developed in this T2D rat model are warranted to define the efficacy of this class of VPI.

Effects of the biliopancreatic diversion on energy balance in the rat

OBJECTIVE

This study was carried out to determine the effects of the biliopancreatic diversion (BPD), a bariatric surgery applied to the treatment of morbidly obese humans, on energy balance in rats.

METHODS

BPD was performed on a group of male Wistar rats. Body weight and food intake were measured daily throughout the study. Feces were also collected to assess energy losses and the determination of digestible energy. Energy expenditure and body composition were also determined for the 50-day length of the protocol. On the day of killing, the brain, the entire intestinal tract and white and brown adipose tissues were collected and weighed. Expression of neuropeptide Y (NPY) and agouti-related protein (AgRP) in the ARC nucleus were assessed by in situ hybridization.

RESULTS

Marked changes in the regulation of energy balance were observed in the BPD-operated rats. A decrease in digestible energy and food intake coupled with an increase in the fecal energy density and protein fecal energy led to an important weight loss in the BPD-operated rats. This weight loss was observed in the loss of fat mass (specifically the white epididymal, inguinal, retroperitoneal and brown adipose tissues). The rats modified their food intake pattern to be able to potentially eat more during the entire day. An increase in the surfaces of all intestinal structures (muscular and mucosal layers) was observed in the BPD-operated rats. The NPY and AgRP expression in the brain were both shown to be greater in the BPD-operated rats than in the control animals. At the beginning of the study, the surgery led to an energy expenditure decrease, which, however, did not persist throughout the study despite the fact that BPD-operated rats exhibited persistent lower fat free masses.

CONCLUSION

BPD led to a noticeable reduction in weight and fat gains in rats, which was in large part owing to a decrease in digestible energy intake led to by the gastrectomy, the intestinal malabsorption inherent to the surgery and to potentially a thermogenesis stimulation that occurred in the second end of the study. The reduction in energy gain occurs despite adaptations to thwart the intestinal malabsorption and the hunger signals from the central nervous system.

Profiling biochemical and hemodynamic markers using chronically instrumented, conscious and unrestrained rats undergoing severe, acute controlled hemorrhagic hypovolemic shock as an integrated in-vivo model system to assess new blood substitutes

The aim of the present study was to assess several biochemical and physiological endpoint parameters alongside controlled hemorrhagic and recovery phases of chronically instrumented, conscious and unrestrained healthy rats. Male Sprague-Dawley rats (12-14 weeks; 430+/-20 g; n=22-18) were instrumented with a saline-perfused femoral arterial catheter and placed individually in a metabolic cage for up to 20 days, allowing instant assessments of the hemodynamic profile and blood and urine sampling for hematological profile and biochemical measurements to assess hepatic, renal and metabolic functions. In addition, body weight, food and water intake, and diuresis were monitored daily. After a 7-day stabilization period, the rats underwent severe and acute hemorrhagic shock (HS) (removal of 50% of total circulating blood volume), kept in hypovolemic shock for an ischemic period of 50 min and then resuscitated over 10 min. Gr. 1 was re-infused with autologous shed blood (AB; n=10) whereas Gr. 2 was infused 1:1 with a solution of sterile saline-albumin (SA; 7% w/v) (n=8-12). Ischemic rats recovered much more rapidly following AB re-infusion than those receiving SA. Normal hemodynamic and biochemical profiles were re-established after 24 h. Depressed blood pressure lasted 4-5 days in SA rats. The hematological profile in the SA resuscitated rats was even more drastically affected. Circulating plasma concentrations of hemoglobin (-40%), hematocrit (-50%), RBC (-40%) and platelets (-41%) counts were still severely decreased 24 h after the acute ischemic event whereas WBC counts increased 2.2-fold by day 4. It took 5-9 days for these profiles to normalize after ischemia-reperfusion with SA. Diuresis increased in both groups (by 45+/-7% on day 1) but presented distinct electrolytic profiles. Hepatic and renal functions were normal in AB rats whereas altered in SA rats. The present set of experiments enabled us to validate a model of HS in conscious rats and the use of an integrated in vivo platform as a valuable tool to characterize HS-induced stress and to test new classes of blood substitutes in real time, post-event, over days.

Role of the Endothelin System in Secondary Pulmonary Hypertension Related to Air Embolism: Lessons Learned from Testing Four Classes of Endothelin Blockers in a Rat Model

A rat model of acute pulmonary air embolism (APAE) was developed. These animals had a higher right ventricular systolic pressure (RVSP) (+ 69% at 15-minute peak, and 21-34% at 30-180 minutes), as well as a reduced mean arterial blood pressure (10-20% at 60-180 minutes), heart rate (20-26% at 60-180 minutes) and PaO2 (9-11% at 30-180 minutes) compared with control rats. The role of the endothelin (ET) system, known to be involved in pulmonary hypertension of various etiologies, was investigated by evaluating the effect of the four classes of ET blockers: ET-converting enzyme inhibitor (ECEi) (CGS 35066), selective endothelin-A receptor antagonist (ETA-Ra) (Atrasentan, ABT-627), endothelin-B receptor antagonist (ETB-Ra) (A-192621) or mixed endothelin-A/endothelin-B receptor antagonist (ETA/B-Ra) (A-182086) in this animal model. All four were effective, to various degrees, at reducing the APAE-induced rise in RVSP. The relative efficacy of those compounds in reducing the acute elevation (15 minutes) of RVSP was ECEi >or= ETA/B-Ra >> ETA-Ra = ETB-Ra. The sustained elevation (30-180 minutes) of RVSP was totally abolished by ECEi and attenuated by other ET blockers with a relative efficacy of ETA-Ra > ETA/B-Ra >or= ETB-Ra. ET receptor antagonists did not affect right ventricular basal tone (control rats) whereas ECEi reduced it by up to 12% after 2 hours. The APAE reduction in mean arterial blood pressure was unaffected by ETARa, was completely normalized by ETB-Ra, but was further reduced by either ETA/B-Ra or ECEi. The basal mean arterial blood pressure in control rats was unaffected by ETA-Ra, was elevated by ETB-Ra, but was depressed by ETA/B-Ra and ECEi. All ET blockers maintained normal oxygen saturation in APAE. These results support a role for ETs in rat APAE, since ET blockers can attenuate the cardiopulmonary deterioration and blood gas exchange. However, modulation of the central hemodynamic profile is more complex and may limit the usefulness of some ET blockers.

Performance of laser-ultrasonic F-SAFT imaging

The resolution and signal-to-noise ratio of laser-ultrasonics to detect small and buried defects can be greatly enhanced by using the synthetic aperture focusing technique (SAFT). Originally developed in the time domain, SAFT can also be implemented in the frequency domain (F-SAFT) using the angular spectrum approach for a significant reduction in processing time. In this paper, an F-SAFT based data processing method especially adapted to laser-ultrasonic data is presented. This method allows for further significant improvements towards laser-ultrasonic imaging of small defects. It includes temporal deconvolution of the waveform data, control for an optimal aperture and frequency bandwidth as well as spatial interpolation of the subsurface images. All the above operations are well adapted to the frequency domain calculations and embedded in the F-SAFT data processing. Also, the aperture control and spatial interpolation allow a reduction of sampling requirements to further decrease both inspection and processing times. The above improvements are illustrated using laser-ultrasonic data taken from an aluminum sample with flat-bottom holes.

Assessment of the subcellular localization of the herpes simplex virus structural protein VP22 in the absence of other viral gene products

We previously demonstrated that the herpes simplex virus type 1 (HSV-1) structural protein VP22 exists in the cytoplasm early in infection and migrates to and accumulates in the nucleus late in infection (J. Virol. 73(8) (1999) 6769). The goal of this study is to document the behavior of VP22 in cells in the absence of other viral polypeptides. We characterized the effects of various indirect immunofluorescence sample preparation conditions on the localization of VP22 in cells and have determined the following. (i) Fixing with formaldehyde and permeabilizing with acetone maintains the structure of microtubules in cells, in as much as we observed classic microtubule organizing centers. (ii) Acetone or methanol alone did not completely fix the cells. (iii) Triton X-100 decreased tubulin immunofluorescence signals in our system. (iv) VP22 predominated in the nucleus of cells that were fixed with formaldehyde. Based on our results, we conclude the following. (v) Due to the partial fixation by acetone or methanol alone, microtubules form diffuse irregular shapes. (vi) VP22 is detected in the cytoplasm of cells fixed with acetone or methanol only due to its seepage from the nucleus. Taken together, these findings indicate that (vii) the nuclear localization of VP22 does not require additional viral factors.

Microtubule reorganization during herpes simplex virus type 1 infection facilitates the nuclear localization of VP22, a major virion tegument protein

Full-length VP22 is necessary for efficient spread of herpes simplex virus type 1 (HSV-1) from cell to cell during the course of productive infection. VP22 is a virion phosphoprotein, and its nuclear localization initiates between 5 and 7 h postinfection (hpi) during the course of synchronized infection. The goal of this study was to determine which features of HSV-1 infection function to regulate the translocation of VP22 into the nucleus. We report the following. (i) HSV-1(F)-induced microtubule rearrangement occurred in infected Vero cells by 13 hpi and was characterized by the loss of obvious microtubule organizing centers (MtOCs). Reformed MtOCs were detected at 25 hpi. (ii) VP22 was observed in the cytoplasm of cells prior to microtubule rearrangement and localized in the nucleus following the process. (iii) Stabilization of microtubules by the addition of taxol increased the accumulation of VP22 in the cytoplasm either during infection or in cells expressing VP22 in the absence of other viral proteins. (iv) While VP22 localized to the nuclei of cells treated with the microtubule depolymerizing agent nocodazole, either taxol or nocodazole treatment prevented optimal HSV-1(F) replication in Vero cells. (v) VP22 migration to the nucleus occurred in the presence of phosphonoacetic acid, indicating that viral DNA and true late protein synthesis were not required for its translocation. Based on these results, we conclude that (iv) microtubule reorganization during HSV-1 infection facilitates the nuclear localization of VP22.

Effect of estrogen replacement therapy on distribution of myocardial blood flow in female anesthetized rabbits

Estrogen replacement therapy reduces risk of cardiovascular events by altering coronary vasoregulation and distribution of blood flow. Vessel reactivity and blood flow distribution were assessed in anesthetized female rabbits in the following groups: 1) sham, 2) ovariectomy, 3) ovariectomy + 17beta-estradiol, and 4) ovariectomy + dehydroepiandrosterone. After a 2-wk treatment, cardiac hemodynamics, vascular reserve, and blood flow were evaluated during the following infusions: 1) NaCl, or vehicle (0.5 ml/min), 2) acetylcholine (2 mg/kg), 3) isoproterenol (2 mg. kg(-1). min(-1)), and 4) chromonar (8 mg/kg). In hearts from ovariectomized rabbits, autoregulatory blood flow was preserved despite lower diastolic perfusion pressures (55 +/- 8 vs. 64 +/- 8 mmHg in sham) and rate-pressure product (14.4 +/- 0.8 vs. 19.3 +/- 0.8 beats/min. mmHg x 10(-3)). Estrogen replacement therapy restored coronary pressure and reserve, and all drugs increased vascular conductance. In conclusion, in hearts from ovariectomized rabbits, vascular reserve declined because coronary pressure was lower; however, blood flow was preserved at a higher level than expected for oxygen demand. Estrogen replacement therapy restores myocardial oxygen supply-demand indices and returns coronary pressure-flow data to levels observed in animals with intact ovaries.

A novel procedure for daily measurements of hemodynamical, hematological, and biochemical parameters in conscious unrestrained rats

Accurate and chronic measurements of various parameters in conscious animals are fundamental for depicting pathological chronic conditions and their etiology in many experimental models, but they are often difficult to achieve. The aim of the present work was to develop and describe step-by-step a reproducible surgical procedure and daily manipulations for continuous, chronic use of conscious rats as models towards a better understanding of various cardiovascular and renal diseases and the testing of novel pharmacological drugs. The complete apparatus involved the use of a series of specialized devices (harness, rotating swivel, revolving arm) supporting a flexible, permanently implanted vascular catheter into the left femoral artery up to the abdominal aorta connected to a miniaturized individual peristaltic pump for delivering fluid at a constant rate. Such a set-up also enabled easy, quick, and reproducible daily blood sampling for the evaluation of more than 20 parameters, including the monitoring of heart rate (HR) and blood pressure in freely moving conscious rats. The overall success and survival rate reached 98% over 14 days and could be extended further. This model represents a much needed and valuable advance in surgical research techniques to evaluate the hemodynamic, hematological, biochemical, pharmacokinetic, and toxicological profile of any new drugs over time in conscious animal models such as rats. What makes this procedure satisfactory is the long-term reliable arterial access and reproducibility of the methodological approach for accurate and continuous measurements, minimizing the stress or invasiveness associated with the use of currently employed systems.

Improved resolution and signal-to-noise ratio in laser-ultrasonics by SAFT processing

Laser-ultrasonics is an emerging nondestructive technique using lasers for the generation and detection of ultrasound which presents numerous advantages for industrial inspection. In this paper, the problem of detection by laser-ultrasonics of small defects within a material is addressed. Experimental results obtained with laser-ultrasonics are processed using the Synthetic Aperture Focusing Technique (SAFT), yielding improved flaw detectability and spatial resolution. Experiments have been performed on an aluminum sample with a contoured back surface and two flat-bottom holes. Practical interest of coupling SAFT to laser-ultrasonics is also discussed.

Factors affecting dropout rate from cognitive-behavioral group treatment for bulimia nervosa

The aim of this study was to retrospectively identify clinical variables assessed prior to treatment which were predictive of patients' dropping out versus completing a 10 week group cognitive-behavioral treatment program for bulimia nervosa. Following a lengthy initial assessment, 81 women meeting DSM-III-R criteria for bulimia nervosa (BN) were referred to one of twelve 10-week groups of 8 to 12 patients having bulimic symptoms. The dropout rate for those meeting full DSM-III-R criteria for BN was found to be 28.7%. A series of seven discriminant function analyses were performed to determine whether dropouts differed from completers in terms of depression, anxiety, difficulties in trust and relating to others, bulimic symptom severity, family environment, weight history and symptom duration and severity of bulimic cognitions. Of these, only the factor assessing difficulties trusting and relating to others was found to significantly discriminate dropouts from completers. Implications of the findings are discussed in terms of clinical and research relevance in the field of eating disorders.

An innovative technical approach for repetitive intratracheal instillation without anesthesia in small animals

Intratracheal instillation in small laboratory animals often involves repeated anesthesia and upper airway intubation. To facilitate this approach, we developed an indwelling system for repeated intratracheal administrations that was assembled from widely available simple components. Its installation can be considered a minor surgical procedure and is done under sterile surgical conditions. This system allows repeated intratracheal administration of substances in the lungs in unanesthetized animals, with the possibility to increase the frequency of instillations and lower the dose. Thoracic radiography was performed to document the reliability of this permanent instillation system. Furthermore, a potent toxic nitrosamine (NNK; N-nitrosamine 4-[nitrosomethylamino]-1-[3-pyridil]-1-butanone) was used to demonstrate appreciable pulmonary toxicity at low dosage but with repetitive administration. This simple technique brings a significant simplification and improvement to small animal studies that require repeated bronchoalveolar administration of substances.

Dynamic polarization coupling in elliptical-core photosensitive optical fiber

The dynamic energy exchange between the two orthogonal modes of an elliptical-core photosensitive optical fiber was measured. We found that the polarization of the light in the fiber always tends to move toward the fast axis, which implies an asymmetry in the photosensitive properties of the fiber.

The role of stress in interpreting the dexamethasone suppression test

Stress has been implicated as a major confounding factor in the interpretation of Dexamethasone Suppression Test (DST) results. This study was designed to examine the effects of stress on DST results. Fifty patients with high levels of acute, chronic, and environmental stress participated in the study. Each patient was given a comprehensive psychiatric and psychological assessment, a routine administration of dexamethasone, and blood tests of cortisol values. The results indicate that the three measures of stress do not appear to affect levels of cortisol suppression, however, all three measures of stress predicted depression. As expected, DST cortisol levels were related to depression. Results are discussed in terms of their implications for understanding the associations among stress, depression and DST results.

Influence of airway resistance on hypoxia-induced periodic breathing

We studied the effects of changing upper airway pressure on the variability of the dynamic response of ventilation to a hypoxic disturbance in 11 spontaneously breathing dogs. Supralaryngeal pressure, instantaneous inspiratory flow, end-expiratory lung volume, and the inspiratory and expiratory O2 and CO2 concentrations were continuously recorded at baseline and after a 1.5-min hypoxic stimulus (abrupt normoxic recovery). Arterial blood gases were obtained at baseline, at the end of the hypoxic period, and after 1 min of recovery. Airway resistances were modified during the recovery by changing the composition of the inspired gas (all with an inspiratory O2 fraction of 20.9%) among four different trials: two trials were realized with air (density 1.12 g/l), and the other two were with He or SF6 (respective density 0.42 and 4.20) in random order. There was no difference between baseline minute ventilation, arterial blood gases, and supralaryngeal resistance values preceding the trials. The hypoxemic and hypocapnic levels and the hypoxia-induced hyperventilation reached during the hypoxic tests were identical for the different hypoxic stimuli. The supralaryngeal resistance measured at peak flow was dramatically influenced by the composition of the inspired gas: 8.8 +/- 1.8 and 6.9 +/- 1.7 (SE) cmH2O.l-1.s with air, 7.2 +/- 2.2 with He, 21.9 +/- 5.5 with SF6 (P less than 0.05). Ventilatory fluctuations were consistently seen during the posthypoxic period. They were characterized by a strength index value (M) (Waggener et al. J. Appl. Physiol. 56: 576-581, 1984).(ABSTRACT TRUNCATED AT 250 WORDS)

Seasonal patterns of bulimia nervosa

OBJECTIVE

The aim of this research was to determine whether a seasonal pattern to symptoms of bulimia nervosa could be identified.

METHOD

In study 1, seasonal patterns of binge-purge frequency and mood were compared between 31 patients with bulimia nervosa and 31 age-matched normal comparison subjects, using a modified (to include binge and purge items) version of the Seasonal Pattern Assessment Questionnaire. Study 2 involved a cross-sectional examination of binge and purge frequency and of depressive symptoms in 197 patients with bulimia nervosa assessed at various months of the year over a 4-year period.

RESULTS

In both the retrospective and cross-sectional studies, binge behavior was found to be highly associated with photoperiod. According to the modified Seasonal Pattern Assessment Questionnaire, purging behavior and mood also varied seasonally among patients with bulimia nervosa. However, purging behavior and severity of depression did not appear to be related to photoperiod in the cross-sectional study. The rate of seasonal affective disorder (syndromal and subsyndromal) defined by the Seasonal Pattern Assessment Questionnaire was higher among the bulimic group than the comparison subjects, but not as high as has been reported for depression in bulimia nervosa.

CONCLUSIONS

The results strongly support the interpretation that symptoms of bulimia nervosa primarily associated with food intake patterns are influenced by seasonal variation, and this effect may be mediated by light availability.

Picosecond photoinduced absorption in photorefractive BaTiO(3)

Picosecond photoinduced absorption in BaTiO(3) has been observed for the first time to our knowledge using picosecond laser pulses and a time delay pump-probe technique. The pump intensity dependence as well as the delay time dependence of the photoinduced absorption coefficient have been measured. The results can be explained qualitatively by a secondary-center model. From our results, the hole recombination time with secondary centers is not larger than 60 ps.

Bronchocutaneous fistula in dogs: influence of fistula size and ventilatory mode on airleak

Bronchocutaneous fistula (BCF) can originate at different levels, from the major airways to the peripheral lung. Little is published on the influence of the fistula origin or the ventilatory effect of the airleak. This study evaluates relative CO2 elimination via fistulas of various size and how different ventilatory modes influence both the quantity and quality, i.e., oxygen and CO2 content, of the airleak. We created BCF with five polyethylene tubings of different diameters (tube 1, 3.0 mm; tube 2, 4.0 mm; tube 3, 5.1 mm; tube 4, 6.4 mm; tube 5, 9.8 mm) in nine dogs. Six modes of ventilation were used with each tubing: spontaneous breathing (SB), pressure support (PS), high frequency (HF), assisted controlled with inspiration set at 20% (AC20) and at 67% (AC67) of the respiratory cycle, and AC20 with an end-expiratory pressure of +10 cm H2O (PEEP). For each ventilatory mode, the fistula air flow (Vf), CO2, and oxygen partial pressure of fistula air (PfCO2 and PfO2) and arterial blood were measured. Vf was measured for all tubes, while gas analysis was done for tubes 1, 3, and 5 only. As expected, Vf increased with tubing size. Vf was higher with AC67 and PEEP than with the other ventilatory modes. PfCO2 was not significantly influenced by the tube size and Vf. Fistula air alveolization was increased only with HF ventilation. Air leaked via the fistula contributed significantly to gas exchange; even when expiration was totally via the fistula, the arterial gases remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Bulimia: independence of antibulimic and antidepressant properties of desipramine

The purpose of this study was to identify variables useful for predicting a positive response to the tricyclic antidepressant desipramine, amongst bulimic subjects. Using a randomized double-blind cross-over design, 24 normal weight bulimics completed a 15-week protocol in which they received either desipramine (150 mg/day) for six weeks, no drug for three weeks, followed by placebo for six weeks, or the reverse sequence. At weeks 0, 2, 4, 6, 9, 11, 13, and 15, each subject was assessed using the EDI, SCL-90, POMS and binge records. The DST, Diagnostic Interview Schedule (DIS), and a personal and family medical-psychiatric history questionnaire were administered at initial assessment, while plasma desipramine levels were obtained at weeks 4 and 13. Responders were defined in terms of both binge frequency reduction, and decrease in depressive symptoms. In the sample of 24 subjects, desipramine was significantly more effective than placebo in reducing the frequency of weekly binging and vomiting, as well as causing a reduction in the fatigue scale of the POMS. No significant effect of the drug was obtained on the EDI or the SCL-90. In terms of reduction in binge frequency, seven responders were identified; another seven were found to be borderline responders, while 10 were labeled as non-responders. The three groups did not differ in terms of their initial scores on the SCL-90, POMS, DST, DIS results, or psychological subscales of the EDI. However, responders were found to have lower EDI bulimia subscale scores, but a higher frequency of purging episodes than were non-responders. Eight patients were identified as borderline responders with respect to depressive symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

The dexamethasone suppression test in bulimia: nonsuppression associated with depression and suboptimal weight

This study was designed to assess the extent to which DST nonsuppression in bulimic women could be predicted by the incidence of major depression in the patient and her family and by other factors known to affect DST results, such as suboptimal weight. The DST was administered to 33 women who met DSM-III criteria for bulimia. Subjects were given a complete psychiatric and psychological assessment, including the National Institute of Mental Health Diagnostic Interview Schedule, a personal and family medical history questionnaire, the Hopkins SCL-90, and the Eating Disorders Inventory. Ideal weight was determined with Metropolitan Life tables. The rate of DST nonsuppression was 58%. Nonsuppression was more frequent among women who suffered from major depression and those who maintained a suboptimal weight. Depression and suboptimal weight were unrelated and thus appear to contribute independently to the high rate of DST abnormalities commonly seen in bulimia.

Treatment of bulimia with desipramine: a double-blind crossover study

The purpose of this study was to evaluate the effect of desipramine, a tricyclic antidepressant with relatively specific noradrenergic effects, on bulimic behaviour, eating attitudes, and mood. Using a double-blind crossover design, 47 normal weight bulimics were randomly assigned to receive either desipramine (150 mg/day) for six weeks, no drug for three weeks, followed by placebo for six weeks, or the reverse sequence. At weeks 0, 2, 4, 6, 9, 11, 13, and 15, each subject was assessed using the EDI, SCL-90, POMS and binge records. Plasma desipramine levels were obtained at weeks 4 and 13. Twenty-four subjects completed the entire fifteen week protocol, while 23 dropped out. Desipramine was significantly more effective than placebo in reducing the frequency of weekly binding, weekly vomiting, and the fatigue scale of the POMS. No significant effect of the drug was obtained on the EDI or the SCL-90. The clinical effect was modest. Desipramine's antibulimic effects were not associated with an alleviation of depressive symptoms.

A comparison of the manifest content in dreams of suicidal, depressed and violent patients

The manifest dream content of psychiatric in-patients who had been admitted because of suicidal attempts was compared with three in-patient control groups, patients who had been admitted for: a) depression and suicidal ideation without attempt; b) depression with no suicidal ideation and; c) commission of a violent act without suicidality. Standardized tests of dream content were used as well as the Beck scale for depression and certain subscales of the MMPI. The results confirmed that both suicidal and violent patients have more death content and destructive violence in their dreams, but that this was a function of the severity of depression and certain character traits such as impulsivity rather than being specific to the behaviour itself. The dream content is continuous with, and probably reflects, the waking state in the case of the depressives. On the other hand some of the findings require a more complex dynamic explanation lending some support to the idea that the dream may have an adaptive function.

A study of the drop-outs in psychopharmacological research with bulimics

Given the high drop-out rates frequently noted in drug trials with bulimic subjects, we have attempted to correlate drop-out status with a greater level of psychopathology as measured by a thorough standardized psychological assessment battery (NIMH-DIS, EDI, POMS and SCL-90). Despite a trend toward higher scores on the Paranoid Ideation Subscale of the SCL-90 among drop-outs compared to completers, there were no significant differences found between the two groups participating in a fifteen week double blind crossover study on the effectiveness of desipramine in bulimia.

Repeated users of a psychiatric emergency service in a Canadian general hospital

The authors of this study examine the demographic and clinical characteristics of repeated users of psychiatric emergency room services in a general hospital. 37.8% of all the patients (913) seen during one year had one or more visits to the emergency room in the six months preceding the index emergency room consultation. Repeaters were more likely than nonrepeaters to be unmarried, self referred and with a history of previous psychiatric treatment for a chronic psychiatric disorder. Factors affecting frequency of use of psychiatric emergency room services among different diagnostic groups were also studied. These results demonstrated the heterogeneity of the needs of the diverse diagnostic groups who over-utilize costly emergency room services. Our findings showed that in a country with universal health insurance, psychiatric emergency services also tend to reflect the gaps in the delivery of health services in the hospital and the community.

Compliance to referrals from the psychiatric emergency room

Factors affecting compliance to referrals in the psychiatric emergency room (ER) were studied in a sample of 468 patients referred for ambulatory care. Compliance was defined as attendance at the first appointment. The overall compliance rate was 59%. Compliance rates were higher among those patients who were receiving psychiatric treatment (active) when they visited the ER. Those in treatment tended to have either Schizophrenic or Personality Disorders with fewer social supports. Different factors affected those in treatment and those not in treatment. The results suggest that those not in treatment would comply more frequently with specific instructions outlining the benefits of psychiatric follow-up.

Pilot electromyographic studies of resting oral activity in obese and normal subjects

Subjects were placed alone in a room where purposeful oral activity such as eating, talking and smoking was not permitted, while activity such as pursing the lips sucking on cheeks, grimaces etc was measured by a specially designed electromyometer. This was done via electrodes attached to the peri-oral area and was recorded in a standardized fashion. In contrast to expectations, total resting activity in the obese did not differ significantly from that of normals. However, the two groups differ in that the time lapse prior to major peaking is significantly shorter in normals than in the obese. Analysis of patterns of both obese and normals suggests cyclic activity of approximately 120 min duration, and this was confirmed with a small group of ten obese subjects. The implications of these findings, in terms of previous work on oral cycles in the obese as well as implications for future research, are discussed.

Distribution of organelles and membranes between hepatocytes and nonhepatocytes in the rat liver parenchyma. A stereological study

When biochemical studies on the liver are interpreted, the cells of the sinusoidal area frequently receive little attention because, compared to hepatocytes, their contribution to subcellular fractions is assumed insignificant. A systematic stereological analysis of liver parenchyma was therefore performed in order to determine the distribution of organelles and membranes between hepatocytic and nonhepatocytic cells, namely endothelial, Kupffer, and fat-storing cells. The livers were fixed by vascular perfusion and the data were corrected for systematic errors dur to section thickness and compression. The extracellular space compartment includes the lumina of sinusoids (10.6%), the space of Disse (4.9%), and the bile canaliculi (0.4%). Hepatocytes constitute 78% of parenchymal volume; the nonhepatocytes account for 6.3% and consist of 2.8% endothelial cells, 2.1% Kupffer cells, and 1.4% fat-storing cells. The nonhepatocytes contribute 55% of the volume of lipid droplets in the liver, 43% of the lysosomes, and 1.2% of the mitochondria. Although the nonhepatocytes account for only 8% of the total surface area of parenchymal membranes, they contain 26.5% of all the plasma membranes, 32.4% of the lysosomal membranes, 15.1% of the Golgi apparatus 6.4% of the endoplasmic reticulum, and 2.4% of the mitochondrial membranes. The data demonstrate the extent to which nonhepatocytic organelles can potentially contaminate subcellular fractions used for biochemical studies. Particularly important for the interpretation of studies on lysosomes, plasma membrane, and Golgi apparatus is the finding that an appreciable part of these organelles may be derived from cell types other than hepatocytes.

Early behavioral and catecholaminergic effects of 6-hydroxydopamine and guanethidine in the neonatal rat

New born rats received 7 consecutive daily injections of 6-hydroxydopamine (6-OHDA) or guanethidine. Locomotor activity, measured at 3 day intervals, was differentially affected by these drugs, although neither drug elimination a characteristic pattern of ontogeny of locomotor activity. Differing neurochemical effects were also observed. 6-OHDA decreased tyrosine hydroxylase activity in cortex and cerebellum, increased it in the brainstem and had no effect on the hypothalamus. Guanethidine slightly elevated enzyme levels in all four brain regions, with the elevation in brainstem significant at 16 days of age. Regional brain changes in enzyme activity after 4 daily 6-OHDA injections beginning at 1, 5 or 9 days of age indicated that toxic effect of 6-OHDA upon catecholaminergic neurons was age dependent. These data are not consistent with a simple interpretation either in terms of maturational changes in blood brain barrier permeability to 6-OHDA or neuronal uptake of the drug. Further analyses of brainstem areas indicated that the increased brainstem enzyme activity after 6-OHDA was restricted to the pons.