bluuebunny/crossref_metadata_2025 huggingface dataset:
Autonomic cardiovascular regulation in patients with obstructive sleep apnoea: a study based on spectral analysis of heart rate variability
Authors: Wiklund  , Olofsson  , Franklin  , Blom  , Bjerle  , Niklasson
Published: March 2003

The aim of this study was to assess the function of the autonomic nervous system in patients with obstructive sleep apnoea syndrome (OSAS). The study was designed as a cross‐sectional case–control study. Fifty‐one patients were included, and the findings were compared with those in 66 controls. Spectral analysis of heart rate variability (HRV) during supine rest, during controlled breathing and after tilting was performed in each patient and control case. The patients performed overnight sleep recordings the night before the HRV recordings. Individuals with an apnoea–hypopnoea index (AHI) above 20 were regarded as OSAS patients and those with AHI lower than 20 as snorers. Differences in HRV and blood pressure between patients and controls were analysed by multiple linear regression with age, body mass index and sex as independent variables. During free and controlled breathing there was a significant decrease in indices reflecting vagal modulation, indicating parasympathetic dysfunction in OSAS patients compared with controls. The mid‐frequency component was also significantly reduced in OSAS patients after tilting but not in the lying position. This may be related to the parasympathetic dysfunction, but could also indicate a decreased sympathetic reserve capacity. We found no significant relation between AHI and indices of vagal modulation in the patient group. Our findings show an autonomic dysfunction in patients with OSAS. The dysfunction involves the parasympathetic system, and may be related to the increased cardiovascular mortality and malignant arrhythmia described in OSAS.
Influence of body size and age on maximal systolic velocity of mitral annulus motion
Authors: Nilsson  , Bojö  , Wandt
Published: March 2003

The maximal systolic velocity of the mitral annulus motion (or maximal systolic long‐axis contraction velocity of the ventricle, MLACV) has been suggested as a means to assess left ventricular function. However, reference values for a wide range of age and body size are lacking. The maximal systolic velocity was studied with M‐mode echocardiography using the apical four‐ and two‐chamber views. Data are reported as the average of the measurements of four sites of the mitral annulus. Fifty‐seven healthy subjects aged 6 months to 72 years were studied. In children and adolescents up to age 18, MLACV had a significant positive correlation with age, height, body surface area, weight and mitral annulus motion amplitude and a significant negative correlation with heart rate. In adults, there was a significant positive correlation between MLACV and height, mitral annulus motion amplitude and body surface area and a significant negative correlation with age and heart rate. Multiple stepwise analysis showed that the maximal systolic velocity is highly dependent on height and age in children and adolescents up to age 18, and on height in adults. The maximal long‐axis contraction velocity (MLACV) can be described by the following equations: MLACV (mm s–1) = 24·0 + 0·34 × height (cm) (Standard Error of the Estimate (SEE)=10·5) in children and adolescents, and MLACV (mm s–1) = –50·5 + 0·75 × height (cm) (SEE=9·8) in adults over 18. There were significant differences between the four sites, with the highest velocity at the lateral site and the lowest velocity at the septal site. No significant difference was found between inspiratory and expiratory beats.
Computerized analysis of video fluorescein imaging (VFI) of the skin
Authors: Lund F. , Jogestrand T. , Kölegård R.
Published: March 2003

Video fluorescein imaging (VFI) is a new technique to continuously follow the development of fluorescence in the skin, i.e. blood inflow and perfusion, after intravenous injection of sodium fluorescein. The method is supplementary to other microcirculatory techniques for evaluation of peripheral arterial occlusive disease, particularly in critical ischaemia. In the present article we describe a totally computerized digital imaging processing system for evaluation and present results from a comparison between the evaluations of the appearance and development of the fluorescence in the sole of the foot using the computerized and the previously used manual techniques. With the computerized system the images are stored and correlated with the start of the injection. Regions of interest are then marked and a mean value of fluorescence intensity is calculated for each image. Using this computerized system the time required for evaluation has been shortened to about 10 min. The results of the comparison between the manual and computerized evaluations of appearance times showed that a significant correlation existed in all examined parts of the feet between the two techniques. The methods gave approximately the same results in regions with fluorescence appearance times between 20 and 50 s. With longer appearance times than approximately 50 s a systematic difference between the two techniques seemed to exist. In this interval shorter appearance times were measured with the computerized technique than with the manual technique. However, the clinical information with regard to prognosis would be relatively unchanged when the new computerized assessment technique and a new cut‐off level for the appearance time are used. Also, regarding the development of fluorescence after the appearance time, expressed by the slope, a significant correlation was found between the manual and the computerized evaluation.
Circadian systemic haemodynamics in borderline and mild hypertension
Authors: Takalo R.
Published: March 2003

Circadian variations in blood pressure (BP), stroke volume (SV), heart rate (HR), cardiac output (CO) and total peripheral resistance (TPR) were determined by a pulse contour method from the intra‐arterial pulse wave in 32 normotensive (NT), 32 borderline hypertensive (BHT) and 31 hypertensive (HT) middle‐aged men. Daytime averages were used as the reference levels. The nocturnal decrease in BP and HR were similar in the three groups. In the night, SV did not change in the NT group, but was increased in the BHT and HT groups. The nocturnal increase in SV may reflect reduced venous capacity causing increased cardiac filling. As a consequence of the difference in SV, the nocturnal CO fall was diminished in the HT group as compared with the NT group. Moreover, TPR had a tendency to decrease in the HT group, which may be considered as a baroreflex response to buffer the expected rise in BP. Five years later, 25 NT, 24 BHT and 19 HT subjects were reassessed using casual BP measurements. In the NT and BHT groups, six and 17 subjects, respectively, had progressed to hypertension. In a logistic regression model for those who became HT, the nocturnal increase in SV was a significant predictor for future hypertension. In conclusion, the results suggest that circadian systemic haemodynamics may be altered before BP is markedly elevated, and that haemodynamic studies might be useful in predicting the development of sustained hypertension.
Automatic computerized analysis of heart rate variability with digital filtering of ectopic beats
Authors: Storck N. , Ericson M. , Lindblad L. E. , Jensen‐Urstad M.
Published: March 2003

Analysis of heart rate variability (HRV) has been used in studies of autonomic function and risk assessment in different patient groups such as in patients with diabetes mellitus, after myocardial infarction (MI) and other cardiovascular disease. Ectopic beats can, however, interfere with HRV analysis and give erroneous results. We have therefore studied the impact of ectopic beats on HRV analysis and the ability of a filter algorithm to correct this. Power spectral analysis of synthetic data with an increasing proportion of ectopic beats and 24‐h Holter recordings from 98 healthy subjects and 93 post MI patients was done with and without digital filtering and interpolation of errors in the data stream. The analysis of HRV was seriously hampered by less than 1% of ectopic beats. A filter algorithm based on detection and linear interpolation of ectopic beats and other noise in the data stream corrected effectively for this in the synthetic data employed. In the healthy subjects and the post MI patients, filtering markedly reduced the extra variability related to non‐normal beats. The software could automatically analyse over one hundred 24‐h files in one batch. HRV analysis should include filtering for ectopic beats even with a small number of such beats. It is possible to make a fast analysis automatically even in huge clinical series, which makes it possible to use the method both clinically and in epidemiological studies.
A practical method to statistically classify devices according to their relative accuracy
Authors: Minini P. , Gaspoz J.–M. , Pichot V. , Costes F. , Roche F. , Lacour J.–R. , Antoniadis A. , Barthélémy J.–C.
Published: March 2003

Mathematical methods to statistically compare the relative accuracy of physiological monitoring devices to reference measurements are scarce. We developed such a method to compare any number of devices to each other as well as to reference values. This new statistical comparative procedure uses a combination of different known mathematical processes. The method allows the separation of the error of the devices into two components, the first, being systematic, can be easily amended, while the second, inherent to the technical limitations of the measuring device as well as to the physical properties of the explored phenomenon, cannot be corrected and will thus be used as the comparative criterion for statistics. That method, which is easy to implement should ease comparisons of the accuracy of any number of devices as well as comparison of other sets of physiological values, by giving an easy access to statistical results.
Long‐term reproducibility of ambulatory blood pressure in unselected elderly subjects
Authors: Wendelin‐Saarenhovi Maria , Isoaho Raimo , Hartiala Jaakko , Helenius Hans , Kivelä Sirkka‐Liisa , Hietanen Eino
Published: March 2003

The aim of this study was to evaluate the long‐term reproducibility and validity of 24‐h ambulatory blood pressure measurements (ABPM) in an unselected elderly population. In a rural Finnish community 503 randomly chosen invited persons over 65 years of age participated and went through 24‐h ABPM. As part of the validation of the methodology, the reproducibility study was conducted in 26 persons (age 65–76 years). Two identical sets of measurement were performed at 4–12 (median 8) month intervals. The agreement between measurements was assessed by correlation coefficients and standard deviation (SD) of the differences. There were no significant differences in 24‐h, daytime and night‐time average diastolic blood pressure (DBP) and daytime average systolic blood pressure (SBP) between the two measurements. During the second measurement, 24‐h SBP and night‐time average SBP were slightly higher than those obtained by the first monitoring. Average 24‐h SBP and DBP were 18 and 7 mmHg lower, respectively, than office blood pressure averages. The correlation coefficients were significantly higher for 24‐h ambulatory blood pressure than for office blood pressure. The SD of the mean difference between visits was significantly lower for 24‐h ambulatory blood pressure than for office blood pressure measurements. These findings show that the long‐term reproducibility of ambulatory blood pressure is good in an elderly unselected population and better than the office blood pressure reproducibility.
Ageing is not associated with a decline in neuromuscular innervation or reduced specific force in men aged 20 and 50 years
Authors: Cannon Jack , Tarpenning Kyle , Kay Derek , Marino Frank E.
Published: March 2003

The exact mechanisms responsible for the decline in strength with age are yet to be completely elucidated. Three proposed mechanisms responsible for the detrimental effect of increasing age on strength include changes in muscle mass, specific force and/or neuromuscular innervation. Thus, the purpose of this investigation was to determine if the age‐related reduction in peak isometric strength was primarily associated with changes in muscle cross‐sectional area, neuromuscular innervation and/or specific force. The cross‐sectional area of the knee extensor muscles (QCSA) was estimated in 13 younger men (YM; 20·8 ± 1·6 years) and eight middle‐aged men (MM; 53·8 ± 4·2 years) prior to performing a series of four maximal voluntary isometric contractions on an isokinetic dynamometer at an angle of 60° knee flexion. Peak force was determined and surface electromyography was sampled from the rectus femoris muscle during each maximal voluntary contraction. The cross‐sectional area of the knee extensor muscles, peak force and integrated electromyography (IEMG) were significantly lower in the MM (P<0·01). However, when peak force and peak IEMG values were corrected for QCSA, there were no significant differences between age groups. These results suggest that the reduction in peak isometric force observed in the MM was primarily associated with quantitative changes in muscle mass, rather than reduced neuromuscular innervation or specific force. Therefore, preserving muscle mass through resistance training may significantly reduce the age‐associated differences in peak strength and assist in promoting quality of life and functional independence in older adults.
Effect of local cold provocation on systolic blood pressure and skin blood flow in the finger
Authors: Bornmyr S. , Castenfors J. , Evander E. , Olsson G. , Hjortsberg U. , Wollmer P.
Published: March 2003

Demonstration of increased vascular cold reactivity in patients with Raynaud’s syndrome is difficult. For medico‐legal reasons, it is important to get objective measures of vasospasm in these patients. Evaluation of the degree of vasospasm also provides prognostic information which is useful for patient management. In this study, we compare two methods of arterial circulation measurement. The laser Doppler scanning is a new method, which uses the recently developed laser Doppler perfusion imaging (LDPI) instrument. The aim of the present study was to compare the effect on finger skin blood flow measured with LDPI with changes in finger systolic blood pressure during local cold provocation. The effect of such provocation, skin blood flow and systolic blood pressure, were studied in 15 healthy controls. Six patients with known traumatic vasospastic disease (TVD) were also tested with both methods. Finger skin blood flow was measured with LDPI on the distal phalanx of the index finger of the left hand, every minutes during 6 min of local heating at 40°C followed by local cooling for 3 min at 15°C and then for 3 min at 10°C. Finger systolic blood pressure was measured with strain‐gauge method before and after local cooling to 10°C with a cuff perfused with water of desired temperature. The test was performed in the same finger within a week of the laser Doppler scanning. Local finger cooling to 15°C and 10°C caused a significant decrease in blood flow, most marked at 10°C. There was, however, no correlation between the decrease in blood flow and blood pressure. In the TVD‐patients decreases in skin blood flow were similar compared with the healthy controls. In contrast, the changes in systolic blood pressure, were outside normal range (systolic quotient <0·65) in five of the six patients (83%), and also in 11 of the 15 healthy controls (73%). In conclusion, there is no correlation between the decrease in finger skin blood flow and systolic blood pressure during local cold provocation. For diagnosis of traumatic vasospastic disease (TVD), local cold‐induced changes in finger systolic blood pressure seems superior to changes in skin blood flow, but the ideal clinical method for demonstrating increased cold‐induced vasospasm is, however, still lacking.
Prediction of post‐operative glomerular filtration rate after nephrectomy for renal malignancy
Authors: Johansson Mats , Moonen Michaela
Published: March 2003

The importance of a correct estimation of contralateral renal function in cases of renal malignancy is obvious, necessitating a conservative approach to tumour resection when function of the contralateral kidney is markedly reduced. The aim of the present study was to determine the accuracy of preoperative gamma camera renography and 51Cr‐EDTA clearance to predict the glomerular filtration rate (GFR) early and up to 6 months after nephrectomy for renal malignancy. Patients (n=40) underwent both gamma camera renography (99mTC‐DTPA) and 51Cr‐EDTA clearance preoperatively, whereas 51Cr‐EDTA clearance was measured within 1 week and up to 6 months after nephrectomy. The single kidney GFR values of the contralateral kidneys were estimated preoperatively and then compared with the post‐operative 51Cr‐EDTA clearance values. The predicted GFR values were lower compared with the measured post‐operative 51Cr‐EDTA clearance values (45 ± 2 vs. 54 ± 3 ml min–1 1 week after nephrectomy and 53 ± 3 ml min–1 6 months later, P<0·01, respectively). The difference between the measured and predicted GFR was larger in patients below the median age of 60 years (P<0·05) and confined to patients with a relative uptake of >30% by the tumour affected kidney. Prediction of post‐operative GFR by non‐invasive renal function tests performed prior to surgery for renal malignancy underestimate post‐operative GFR when the function of the tumour affected kidney is preserved, indicating an adaptive GFR increase in these cases.
Peritoneal fluid cytology in serous borderline tumours of the ovary
Authors: STEWART  , KENNEDY
Published: March 2003

stewart c. j. r. and kennedy j. h. (1998) Cytopathology9, 38–45

Peritoneal fluid cytology in serous borderline tumours of the ovary

Peritoneal fluid cytology findings in three patients with serous borderline tumours of the ovary and peritoneal serous implants are presented. The specimens were characterized by papillary groups, acinar clusters and single neoplastic cells exhibiting cytoplasmic vacuolation and nuclear atypia of variable degree. The cytological appearances were initially considered consistent with ovarian adenocarcinoma in all cases. Histological correlation is required to avoid this diagnostic pitfall.
Fine needle aspiration (FNA) cytology of Rosai Dorfman disease
Authors: Deshpande V. , Verma K.
Published: March 2003

deshpande v and verma k. (1998) Cytopathology9, 329–335

Fine needle aspiration (FNA) cytology of Rosai Dorfman disease

Rosai Dorfman disease (sinus histiocytosis with massive lymphadenopathy (SHML)) is a benign self‐limiting disorder that commonly involves the lymph nodes. We reviewed eight cases of this entity aiming to document the cytomorphological features. Of the eight cases, a preoperative diagnosis was suggested in seven cases. Pertinent features included: numerous large histiocytes with prominent emperipolesis (documented by a halo around the cell), fine vacuoles in the cytoplasm and lymphocytes and plasma cells in the background. In some cases the histiocytes showed atypia. In one biopsy‐proven case a diagnosis of Hodgkin's was suggested, emphasizing the pitfalls associated with the FNA diagnosis of this lesion.
Metaplastic carcinomas of the breast—fine needle aspiration (FNA) cytology findings
Authors: NOGUEIRA M. , MENDONÇA S. ANDRÉ AND E.
Published: March 2003

nogueira m., andré s. and mendonça e.. (1998) Cytopathology9, 291–300

Metaplastic carcinomas of the breast—fine needle aspiration (FNA) cytology findings

Metaplastic carcinomas of the breast are defined by mesenchymal and/or squamous cell components associated with ductal carcinoma and may raise diagnostic problems in FNA cytology. We reviewed FNA smears of a series of nine cases; seven were compared with histological sections and two with cell‐block sections. The cytological pattern was diagnostic of carcinoma in six cases; in two cases a diagnosis of sarcoma/phyllodes tumour was considered, as cells were predominantly spindle‐shaped. One case had a pleomorphic adenoma type pattern. The cytological findings suggesting a diagnosis of metaplastic carcinoma include a liquid aspirate, a proteinaceous or chondromyxoid background and a poorly differentiated tumour with multinucleated giant cells, neoplastic or histiocytic. A definite diagnosis requires the presence of both carcinomatous and metaplastic (squamous/mesenchymal) components.
Cytological findings of abdominal malignant leiomyoblastoma (epithelioid leiomyosarcoma) in ascitic fluid; a case report
Authors: Patinakis P. A. , Vlachou M. , Kyziridou A. , Platanias CH. , Panagiotou S. , Toliou TH. , Destouni CH.
Published: March 2003

Introduction
Fine needle aspiration cytology (FNAC) detection of early renal allograft infection with Candida glabrata—a case report
Authors: Hughes D. A. , Davies D. R. , Young R. , Toogood G. J. , Roake J. A. , Gray D. W. R. , Morris P. J.
Published: March 2003

Introduction
Reactivity of six antibodies in effusions of mesothelioma, adenocarcinoma and mesotheliosis: stepwise logistic regression analysis
Authors: Dejmek A. , Hjerpe A.
Published: March 2003

Reactivity of six antibodies in effusions of mesothelioma, adenocarcinoma and mesotheliosis: stepwise logistic regression analysis

Anti‐CEA, anti‐vimentin, CAM5.2, BerEp4, Leu‐M1 and anti‐EMA were applied to effusions from 36 mesotheliomas, 53 adenocarcinomas and 24 reactive mesothelial proliferations. Stepwise logistic regression analysis selected three criteria of major importance for distinguishing between adenocarcinoma and mesothelioma: BerEp4, CEA and EMA accentuated at the cell membrane (mEMA), these three being of similar diagnostic value. The pattern BerEp4−, CEA− and mEMA+ was fully predictive for mesothelioma (sensitivity 47%), whereas the opposite pattern was fully predictive for adenocarcinoma (sensitivity 80%). Only EMA seemed to distinguish between mesotheliosis and mesothelioma. Comparison of reactivity in cytological and histological material from the same mesotheliomas showed similar staining frequencies for CEA and CAM5.2, with some random variation for Leu‐M1 and EMA, whereas vimentin and BerEp4 reactivity was more frequent in cytological specimens.
Significance of high‐risk human papillomavirus detection by polymerase chain reaction in primary cervical cancer screening
Authors: Oh Y. L. , Shin K. J. , Han J. , Kim D. S.
Published: March 2003

Significance of high‐risk human papillomavirus detection by polymerase chain reaction in primary cervical cancer screening

The purposes of this study were to evaluate the incidence of high‐risk human papillomavirus (HPV) infection by polymerase chain reaction (PCR) and to assess its diagnostic usefulness in primary cervical screening. PCR testing for HPV type 16, 18, 31 and 33 was performed on 1305 specimens obtained during routine cervical cancer screening. We analysed the concurrent cervical smears and biopsy, and correlated them with the HPV infection status. We also evaluated histologically‐proven cases with ASCUS smears according to HPV infection. HPV DNA was identified in eight (0.7%) of 1144 cytologically normal patients; nine (10.5%) of 86 ASCUS; seven (25.0%) of 28 LSIL; 26 (78.8%) of 33 HSIL; and in all of three squamous cell carcinomas (SCC). HPV positivity was significantly associated with cytohistological diagnosis for HSIL of more. In addition, HPV‐positive ASCUS cases were found to be associated with histological abnormality rather than HPV‐negative. The results indicate that high‐risk HPV testing by PCR could be a useful adjunct tool for Pap smear in primary cervical screening. The combination of Pap smear and high‐risk HPV testing by PCR might reduce unnecessary colposcopy‐guided biopsy of women with cytological diagnosis of ASCUS.
p53 protein expression and oestrogen and progesterone receptor status in invasive ductal breast carcinomas
Authors: Ioakim‐Liossi A. , Karakitsos P. , Markopoulos C. , Aroni K. , Athanassiadou P. , Delivelioti K. , Athanassiades P. , Vaiopoulos G.
Published: March 2003

p53 protein expression and oestrogen and progesterone receptor status in invasive ductal breast carcinomas

The p53 protein expression and oestrogen and progesterone receptors status was investigated in correlation to the grade of malignancy of primary breast carcinomas. Our material constituted imprints from surgical biopsies of 75 invasive ductal breast cancer cases. The p53 protein expression was investigated immunocytologically using the monoclonal antibody p53 DO‐7 (DAKO). A biochemical DCC method was applied for the detection of oestrogen and progesterone receptors for all tumours. Fifty‐one percent of breast cancer cases were p53 protein positive. A statistically significant association of p53 protein expression and high tumour grade was found (χ2=23.72, d.f.=2, P < 0.001). A statistically significant association was also found between oestrogen and progesterone receptor positive cases and the grade of malignancy (P < 0.001). A negative association between p53 protein expression and oestrogen (ER) and progesterone receptors (PgR) positivity was found. From our results it appears that it is possible to distinguish from grade II tumours two subgroups of cases, one with low malignancy potential and p53 (–), ER (+), PgR (+), and another subgroup with high malignancy potential and phenotype p53 (+), ER (–), PgR (–). The last subset of patients could actually benefit from adjuvant therapy.
Evidence for direct learning curve for technique on change of cervical sampling device
Authors: CROSS P. A. , JONES M. R. , BUTLER C. R. , CHARLTON C. R.
Published: March 2003

Evidence for direct learning curve for technique on change of cervical sampling device

The recommended sampling device within the NHS Cervical Screening Programme is the Aylesbury spatula. A local decision was taken to decrease brush usage (either alone or in combination) by 50% from an initial level of 41.8%, with an initial inadequate smear rate of 9.93%. This was managed by controlling smear taking equipment through provision of smear taking kits. The monthly inadequate rate unexpectedly rose to 17.8% before dropping back to previous levels. Brush usage overall fell to 35.2%, with a corresponding increase in spatula use. The possible reasons for this are discussed. The facts suggest that these changes were directly linked, and that there is a learning curve with change of sampling device and that a rise in the inadequate rate should be expected under these circumstances.
An audit of the accuracy of fine needle aspiration using a liquid‐based cytology system in the setting of a rapid access breast clinic
Authors: Joseph L. , Edwards J. M. , Nicholson C. M. , Pitt M. A. , Howat A. J.
Published: March 2003

We have assessed the effectiveness and accuracy of reporting fine needle aspirates of the breast (FNAB) using a liquid‐based cytology (LBC) system (the Cytospin® method) in the pressure situation of a rapid access clinic (RAC). We have reviewed every case from the RAC from June 1997 to February 2001 inclusive. There were 1322 cases, which accounted for 26% of the total FNAB received in our department over the period. There were 323 cancers and 999 benign cases in the group. The inadequate/nondiagnostic rate (C1) was 18%. The absolute sensitivity, including C1 cases, was 73% with the complete sensitivity being 90%. The groups of ‘atypical, probably benign’ (C3) and ‘suspicious, probably malignant’ (C4) accounted for a total of 6.2%. There were 28 false negative cases and 1 false positive case (a borderline phyllodes tumour).

Comparing our results with the standards recommended by the NHSBSP has shown that the diagnosis of FNAB using this LBC method is feasible, accurate and reliable even in the pressure situation of a RAC.
Impact of diet quality on demographic attributes in adult grasshoppers and the nitrogen limitation hypothesis
Authors: JOERN ANTHONY , BEHMER SPENCER T.
Published: March 2003

1. Various formulations of the nutrient stress hypothesis predict that insect herbivore populations will respond positively to increased nutrient quality of host plants, especially dietary nitrogen. Survival and reproduction by adult females of two grasshopper species [Acrididae;Melanoplus sanguinipes (Fabricius) and Phoetaliotes nebrascensis (Thomas)] were evaluated in response to defined diets that varied factorially in both total nitrogen (1–7%) and total soluble carbohydrate (4.3–26.7%). These grasshopper species coexist naturally but are typically shifted phenologically so that specific developmental stages normally encounter host plants of different nutritional quality under natural conditions.

2. Demographic responses by adult females of both species varied according to diet quality, but not in the same fashion. Diet quality affected survival significantly in P. nebrascensis but not in M. sanguinipes. Survival in P. nebrascensis was greatest on diets containing the lowest nitrogen concentrations; carbohydrate level had no effect.

3. Diet quality influenced reproduction significantly in both species. Egg production rate (eggs/day) in M. sanguinipes exhibited a negative linear response to increased carbohydrate, coupled with a significant quadratic response to nitrogen that reached a maximum at an intermediate level of about 4% total N. A significant quadratic response to total N for pod production rate (indicating the timing of reproduction) was also observed. Clutch size in M. sanguinipes exhibited a negative relationship with total carbohydrate in the diet, but no response to nitrogen. No interaction was observed between nitrogen and carbohydrate levels. For P. nebrascensis, response to diet quality was much weaker, with only a suggestive maximum at 4% total‐N for both egg production rate (eggs/day) and clutch size (eggs/pod) and a suggestive linear response for pod production rate as carbohydrate level increased. Female body weight did not contribute to any reproductive response as a covariate variable.

4. Combined with a similar, previous analysis of demographic responses by the grass‐feeding grasshopper, Ageneotettix deorum, these results challenge the ability to draw generalizations about host plant nutritional quality and grasshopper demographic responses. These three grasshopper species respond quite differently to defined diets that vary in total nitrogen and carbohydrate levels. Thus, although host plant quality can contribute significantly to grasshopper population responses, a uniform explanation is not likely.
Feeding strategies in drosophilid parasitoids: the impact of natural food resources on energy reserves in females
Authors: EIJS IRENE E. M. , ELLERS JACINTHA , VAN DUINEN GERT‐JAN
Published: March 2003

1. Adult feeding strongly increases longevity and fecundity in parasitic wasps. Searching for food resources involves costs; therefore, it is advantageous to be able to feed on the breeding substrate.

2. Cohorts of females of four drosophilid parasitoid species were assigned to different food treatments including starvation. Fat contents were measured and compared after 5 days. In this way the nutritional value of breeding substrates to females could be expressed in terms of energy reserves.

3. Three of the four species tested fed on natural breeding substrates. A fourth species did not produce evidence of such feeding. However, this species fed on honey when fat reserves were low.

4. Feeding is related to: (i) the species’ natural breeding substrate, (ii) the energy allocation and lifetime expectancy of the female, and (iii) time of the season.

5. Because feeding strongly influences longevity and fecundity, it is argued that the different feeding strategies found may affect competitive relationships between these drosophilid parasitoid species.
Effect of food plant switching by a herbivore on its parasitoid: Cotesia melanoscela development in Lymantria dispar exposed to reciprocal dietary crosses
Authors: Kruse James J. , Raffa Kenneth F.
Published: March 2003

1. Host plant switching by dispersing early instar lepidopterans could have implications for parasitoid performance, but this possibility has not been evaluated thoroughly.

2. The relative growth rates ofLymantria disparparasitized byCotesia melanoscela, and the weight of larvae at the time of parasitoid emergence, were affected most by the second larval food plant consumed.

3. The relative growth rates, pupal weights, weight of larva at the time of parasitoid emergence, and development times ofL. disparwere affected significantly by the second larval food plant consumed.

4. Development time and size ofCotesia melanoscelawere affected most by the second larval food plant consumed.

5. Parasitoid performance was affected most by the larval host’s relative growth rate and the final weight of the host larva at the time of parasitoid emergence.

6. Host plant switching affected the weight ofL. disparlarvae at the time of parasitoid emergence, but the effect of switchingper sewas not a significant factor inC. melanoscelasize or development.

7.Lymantria disparlarvae that fed onPopulusas their second host outperformed larvae that fed ultimately onAcer.

8. Parasitoids yielded fromL. disparlarvae that fed ultimately onPopulusoutperformed parasitoids yielded from larvae that fed ultimately onAcer.

9. Per cent mortality ofL. dispardue to parasitism and percentage adultC. melanoscelaemergence were highest in parasitized larvae fedPopulus, poor in hosts fedAcer, and intermediate in switching larvae.
Variation in herbivory by Yponomeuta mahalebella on its only host plant Prunus mahaleb along an elevational gradient
Authors: Alonso Conchita
Published: March 2003

1. The effect of natural variation in abiotic conditions on the herbivory interaction between Prunus mahaleb (Rosaceae) and its monophagous folivore, larvae of Yponomeuta mahalebella (Lepidoptera, Yponomeutidae), was analysed for 2 consecutive years along an elevational gradient in Sierra de Cazorla, south‐east Spain.

2. There was a negative correlation between site elevation and mean population herbivory level measured at the end of the growing period of Y. mahalebella. Mortality during larval development was higher at higher elevation sites, and mean adult body mass was higher in lower elevation populations.

3. Variation in temperatures recorded during the larval growth period at different altitudes was the only study factor related to abundance of Y. mahalebella larvae; neither differences in parasitisation rates nor plant features covaried significantly with herbivore abundance.

4. These results support the existence of geographical variation in plant–animal interactions in relation to environmental heterogeneity.
Reproductive allocation and reproductive ecology of seven species of Diptera
Authors: Bonduriansky Russell , Brooks Ronald J.
Published: March 2003

1. Variation in resource allocation to egg size and number was investigated in seven sympatric species of Piophilidae that oviposit on carcasses or discarded cervid antlers: Liopiophila varipes (Meigen), Prochyliza xanthostoma Walker, Protopiophila latipes (Meigen), Protopiophila litigata Bonduriansky, Stearibia nigriceps (Meigen), and two unidentified species of Parapiophila McAlpine.

2. Following optimal reproductive allocation theory, relatively larger, fewer eggs were expected in (1) species that oviposit on antlers, where larvae probably experience lower risk of predation and greater competition than larvae in carcasses, and (2) species with aggressive males and male‐biased sex ratios on the oviposition substrate, where risk of injury during oviposition may have favoured females laying fewer eggs.

3. Variation in reproductive allocation strategies could not be explained by known differences in larval or adult environment, but congeneric species clustered by reproductive allocation patterns. The Parapiophila species produced larger, fewer eggs than the other species, and egg number increased slowly with body size. The Protopiophila species did not deviate from expected egg sizes and numbers, and egg number increased steeply with body size.

4. An interspecific egg size–egg number trade‐off resulted in a tight linear scaling of ovary volume to body size, suggesting common physiological constraints on relative ovary mass.

5. Within each species, egg size was nearly constant whereas egg number increased with female body size, suggesting species‐specific stabilising selection on egg size.
Influence of host size on oviposition behaviour and fitness of Elachertus cacoeciae attacking a low‐density population of spruce budworm Choristoneura fumiferana larvae
Authors: Fidgen Jeffrey G. , Eveleigh Eldon S. , Quiring Dan T.
Published: March 2003

1. Oviposition behaviour and host size − fitness relationships of a gregarious, idiobiont ectoparasitoid, Elachertus cacoeciae (Howard) (Hymenoptera: Eulophidae), were studied by implanting one fourth‐, fifth‐, and sixth‐instar spruce budworm Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae) larva per tree in a stand where the density of the wild C. fumiferana population was low.

2. Development time of E. cacoeciae larvae was quickest on fifth‐instar C. fumiferana larvae, which were the preferred hosts for oviposition.

3. Brood sex ratio (proportion of females) was related positively to increasing C. fumiferana instar, indicating that more females were laid on larger hosts.

4. Parasitoid offspring size increased with increasing C. fumiferana instar and decreased with increasing brood size on smaller hosts. Female but not male size was related positively to increasing brood sex ratio (proportion of females).

5. Under laboratory conditions, parasitoid longevity was related positively to parasitoid size and realised lifetime fecundity, and clutch size was related positively to host size.

6. These results suggest that selection of intermediate‐sized C. fumiferana larvae may be adaptive for E. cacoeciae.
The effects of abiotically induced changes in host plant quality (and morphology) on a salt marsh planthopper and its parasitoid
Authors: Moon Daniel C. , Rossi Anthony M. , Stiling Peter
Published: March 2003

1. In this study, the effects of shading and fertilisation on the density of the salt marsh planthopperPissonotus quadripustulatus(Homoptera: Delphacidae), which is monophagous onBorrichia frutescens(Asteraceae), were assessed. The effects of these abiotic factors on the rate at whichPissonotuseggs were parasitised byAnagrussp. nrarmatus(Hymenoptera: Mymaridae) were also examined.

2. Field plots were shaded by shade cloth suspended above the plots, and fertilised by the application of NH4NO3fertiliser. Both shading and fertiliser increased plant foliar nitrogen levels significantly. Both shading and fertiliser also increased the density ofPissonotus, presumably because of their effect on plant quality.

3. In addition, both shading and fertiliser increased the percentage ofPissonotuseggs parasitised byAnagrus. This increase in parasitism is probably attributable to changes in host plant morphology induced by the treatments.

4. The results of this study suggest that in stressful environments such as salt marshes, changes in the abiotic environment may play an important role in shaping the community by directly affecting organisms on multiple trophic levels.
The relationship between host selection behaviour and offspring fitness in a koinobiont parasitoid
Authors: Rivero Ana
Published: March 2003

1. When host quality varies, optimal foraging theory assumes that parasitic wasps select hosts in a manner that increases their individual fitness. In koinobiont parasitoids, where the hosts continue developing for a certain period of time after parasitisation, host selection may not reflect current host quality but may be based on an assessment of future growth rates and resources available for the developing larvae.

2. When presented with hosts of uniform quality, the koinobiont parasitoid Leptomastix dactylopii exhibits a characteristic host‐selection behaviour: some hosts are accepted for oviposition on first encounter, while others are rejected several times before an egg is laid in them, a behaviour that is commonly associated with a changing host acceptance threshold during the course of a foraging bout.

3. The fitness of the offspring that emerged from hosts accepted immediately upon encounter was compared with the fitness of offspring emerged from hosts rejected several times before being accepted for oviposition.

4. The pattern of host acceptance and rejection was not related to any of the measured fitness parameters of the offspring emerging from these hosts (development time, size at emergence, sex ratio at emergence, and female offspring egg load).

5. While complex post facto adaptive explanations can be devised to explain the nature of such a time and energy consuming host selection process, it is suggested that physiological constraints on egg production or oviposition may provide an alternative, purely mechanistic, explanation for the results obtained.
Foraging behaviour of caterpillars given a choice of plant genotypes in the presence of insect predators
Authors: Stamp Nancy E. , Bowers M. Deane
Published: March 2003

1. To examine the effects of predators and plant genotype on the behaviour, patterns of herbivory, growth, and survivorship of caterpillars, an experiment was conducted under semi‐natural conditions, with two host plant genotypes (low vs. high iridoid glycosides) of plantain Plantago lanceolata, two kinds of herbivores (noncryptic specialist Junonia coenia vs. cryptic generalist Pyrrharctia isabella), and two levels of caterpillar predation (with and without Podisus maculiventris stinkbugs).

2. Choice tests conducted in the laboratory showed that in three out of four cases, caterpillars preferred leaves from the low iridoid glycoside genotype.

3. In the field experiment, the presence of predators affected the amount of leaf material eaten per plot and the proportion of leaf material eaten by the caterpillars as expected, but it did not affect the use of plant genotypes by Junonia caterpillars within the plots. In contrast, the caterpillar density–predation treatments affected the proportion of leaves eaten by Pyrrharctia caterpillars that were of the low iridoid glycoside genotype, but not entirely as expected. The caterpillars used both genotypes equally when predators were present but the high iridoid glycoside genotype was used more by caterpillars at low density and without predators.

4. The message then is that on the scale that caterpillars could be choosy about intake of iridoid glycosides they were not choosy among plant genotypes; however they were choosy between leaves, which can differ in iridoid glycoside concentration via plant genotype and leaf age.
The role of olfactory stimuli in the location of weakened hosts by twig‐infestingPityophthorusspp.
Authors: Bonello Pierluigi , Mcnee William R. , Storer Andrew J. , Wood David L. , Gordon Thomas R.
Published: March 2003

1. Senescing, shade‐suppressed, or broken branches of Monterey pinePinus radiataare infested by twig beetles in the genusPityophthorus(Coleoptera: Scolytidae). The studies reported here tested whether twig beetles can discriminate between healthy and pitch canker‐diseased branches, whether diseased branch tips produce more ethylene than undamaged controls, and whether ethylene and other volatiles, produced by the plant in response to tissue damage, are utilised by twig beetles in host location.

2. Significantly greater numbers of twig beetles were reared from pitch canker‐symptomatic than from pitch canker‐asymptomatic branches of Monterey pine collected in the field.

3. Needles of Monterey pine branches inoculated with the pitch canker fungal pathogenFusarium circinatumproduced significantly higher levels of ethylene than needles of control branches, and this was evident just prior to, and during, symptom expression.

4. In trapping studies in which pheromone production was prevented, there was no evidence of attraction of twig beetles to a source of ethylene alone, to cut host branches, or to cut branches treated with the ethylene‐releasing compound, ethephon. The results suggest that twig beetles identify weakened branches after landing.
The response of Hyssopus pallidus to hosts previously parasitised by Ascogaster quadridentata: heterospecific discrimination and host quality
Authors: Zaviezo Tania , Mills Nick
Published: March 2003

1. Two basic tenets of competition among parasitoids, that taxonomically distinct parasitoids are unable to discriminate against hosts that have previously been attacked by a competitor and that previous parasitism reduces the quality of a host, were tested by monitoring the oviposition response of Hyssopus pallidus, a gregarious ectoparasitoid, to healthy codling moth larvae and codling moth larvae that had previously been parasitised by a solitary endoparasitoid, Ascogaster quadridentata.

2. Hyssopus pallidus accepted both categories of host larva for oviposition when its competitor was constrained as a first‐instar larva by the diapause development of its host, but discriminated against previously parasitised host larvae when its competitor was present as a larger larva in a non‐diapausing host.

3. Hyssopus pallidus distinguished between the two categories of host larva by allocating twice as many eggs to host larvae previously parasitised by A. quadridentata, a response that was not influenced by previous oviposition experience.

4. The larger clutch sizes allocated to previously parasitised host larvae produced twice as many female progeny, each of a typical size, such that the total biomass was twice that produced from the smaller clutches laid on healthy host larvae. Possible confounding influences of host age and diapause are discounted.

5. These results demonstrate that interspecific discrimination does occur in H. pallidus and that host quality can be improved through previous parasitism by an endoparasitoid. Although interspecific discrimination appears rare among insect parasitoids, it may have been overlooked among ectoparasitoids and requires examination of the fitness consequences of interspecific interactions to clarify its adaptive significance.
Detrimental effects of latex and cardiac glycosides on survival and growth of first‐instar monarch butterfly larvae Danaus plexippus feeding on the sandhill milkweed Asclepias humistrata
Authors: Zalucki Myron P. , Brower Lincoln P. , Alonso‐M Alfonso
Published: March 2003

1. A novel experimental method was developed to study negative physical and chemical effects of latex and cardiac glycosides on first‐instar monarch butterfly larvae in their natural environment in north central Florida. Forceps were used to nibble through the petioles of leaves of the sandhill milkweed Asclepias humistrata, mimicking the behaviour of mature monarch larvae. This notching cut off the supply of latex to the leaves without significantly reducing either their cardiac glycoside concentration or water content.

2. The mean cardiac glycoside concentration in larvae that fed on intact leaves was nearly two and a half times greater than in larvae that fed on notched leaves. This was probably because more latex is present in the gut of the larvae that fed on the intact leaves. Supporting this is the fact that the mean concentration of cardiac glycosides in the latex was 34–47 times that in the leaves.

3. Wet weights, dry weights, and growth rates of first‐instar larvae that fed on intact leaves over a 72‐h period were less than half those of larvae that fed on notched leaves.

4. Mortality due to miring in the latex was 27% on the intact leaves compared with 2% on the notched leaves.

5. Latex, cardiac glycosides, and other as yet undetermined plant factors all have a negative effect on first‐instar larval survival.

6. Video‐analyses indicated that ingestion of latex caused the larvae to become cataleptic and increased their chances of being mired on the leaf by the setting latex glue. Dysfunction resulting from latex ingestion may lead to the larvae falling off the plant and being killed by invertebrate predators.

7. The difficulty of neonate monarch larvae surviving on A. humistrata – one of the principal milkweed species fed on each spring as monarchs remigrate from Mexico into the southern U.S.A. – is evidence that a co‐evolutionary arms race is operating in this plant–herbivore system.