Two closely located areas in the suboesophageal ganglion and the tritocerebrum receive projections of gustatory receptor neurons located on the antennae and the proboscis in the moth Heliothis virescens

Sucrose stimulation of gustatory receptor neurons on the antennae, the tarsi, and the mouthparts elicits the proboscis extension reflex in many insect species, including lepidopterans. The sensory pathways involved in this reflex have only partly been investigated, and in hymenopterans only. The present paper concerns the pathways of the gustatory receptor neurons on the antennae and on the proboscis involved in the proboscis extension reflex in the moth Heliothis virescens (Lepidoptera; Noctuidae). Fluorescent dyes were applied to the contact chemosensilla, sensilla chaetica on the antennae, and sensilla styloconica on the proboscis, permitting tracing of the axons of the gustatory receptor neurons in the central nervous system. The stained axons showed projections from the two appendages in two closely located but distinct areas in the suboesophageal ganglion (SOG)/tritocerebrum. The projections of the antennal gustatory receptor neurons were located posterior-laterally to those from the proboscis. Electrophysiological recordings from the receptor neurons in s. chaetica during mechanical and chemical stimulation were performed, showing responses of one mechanosensory and of several gustatory receptor neurons. Separate neurons showed excitatory responses to sucrose and sinigrin. The effect of these two tastants on the proboscis extension reflex was tested by repeated stimulations with solutions of the two compounds. Whereas sucrose elicited extension in 100% of the individuals in all repetitions, sinigrin elicited extension in fewer individuals, a number that decreased with repeated stimulation.     

A randomized study on migration of the Spectron EF and the Charnley flanged 40 cemented femoral components using radiostereometric analysis at 2 years

Background and purpose

We performed a randomized study to determine the migration patterns of the Spectron EF femoral stem and to compare them with those of the Charnley stem, which is regarded by many as the gold standard for comparison of implants due to its extensive documentation.

Patients and methods

150 patients with a mean age of 70 years were randomized, single-blinded, to receive either a cemented Charnley flanged 40 monoblock, stainless steel, vaquasheen surface femoral stem with a 22.2-mm head (n = 30) or a cemented Spectron EF modular, matte, straight, collared, cobalt-chrome femoral stem with a 28-mm femoral head and a roughened proximal third of the stem (n = 120). The patients were followed with repeated radiostereometric analysis for 2 years to assess migration.

Results

At 2 years, stem retroversion was 2.3° and 0.7° (p < 0.001) and posterior translation was 0.44 mm and 0.17 mm (p = 0.002) for the Charnley group (n = 26) and the Spectron EF group (n = 74), respectively. Subsidence was 0.26 mm for the Charnley and 0.20 mm for the Spectron EF (p = 0.5).

Interpretation

The Spectron EF femoral stem was more stable than the Charnley flanged 40 stem in our study when evaluated at 2 years. In a report from the Norwegian arthroplasty register, the Spectron EF stem had a higher revision rate due to aseptic loosening beyond 5 years than the Charnley. Initial stability is not invariably related to good long-term results. Our results emphasize the importance of prospective long-term follow-up of prosthetic implants in clinical trials and national registries and a stepwise introduction of implants.Femoral stem loosening in cemented total hip arthroplasty (THA) is a multifactorial process with different mechanisms (Gruen et al. 1979, Barrack 2000). Factors such as the material, design, and surface finish are of fundamental importance for the long-term performance of cemented femoral hip implants (Scheerlinck and Casteleyn 2006). The longevity of cemented femoral stems has been related to the quality, stability, and endurance of the bonding between stem and cement (Chang et al. 1998, Scheerlinck and Casteleyn 2006). Different femoral stem designs have been developed to obtain increased fixation at this interface, since debonding between the cement and stem is an important mechanism in the initiation of loosening (Jasty et al. 1991).The satin-finish Spectron femoral stem has been one of the best performing stems in the Swedish National Arthroplasty Register (Malchau et al. 2002). A modified, proximally roughened version of the Spectron stem, the Spectron EF (Smith and Nephew, Memphis, TN), was introduced in 1989 to enhance stem-cement bonding.The use of this implant gained increasing popularity, and in 2007 the Spectron EF stem used with the Reflection All-Poly acetabular cup (Smith and Nephew) was the most commonly used primary total hip prosthesis in Norway (Espehaug et al. 2009).The degree of migration during the first years after surgery has been shown to correlate with the long-term performance of joint prostheses (Kärrholm et al. 1994, Kobayashi et al. 1997). Radiostereometric analysis (RSA) allows the accurate measurement of implant movement and has been extensively used for measurement of the in vivo migration of implants (Kärrholm et al. 1997).An earlier prospective randomized study reported an increased revision rate of the Charnley stem compared to the satin-finished Spectron stem (Garellick et al. 1999). In the present randomized, controlled clinical trial we wanted to evaluate the early migration of the successor to this stem, the Spectron EF stem and to compare it to that of the Charnley stem using RSA. The null hypothesis was that the migration of the Spectron EF stem was equal to that of the Charnley prosthesis (DePuy International Ltd., Leeds, UK), which has the longest follow-up and the largest volume of documentation of implants used for primary total hip arthroplasty (Aamodt et al. 2004).     

Determinants of ICU mortality in necrotizing pancreatitis: the influence of Staphylococcus epidermidis

BACKGROUND: The severity of acute necrotizing pancreatitis ranges from self-limited to rapidly progressive illness leading to multiple organ failure. Several scoring systems and clinical parameters have been used to predict the course of the disease. The aim of this study was to evaluate the clinical and microbiological determinants of poor outcome in necrotizing acute pancreatitis. METHODS: Medical records of 67 consecutive patients admitted to the intensive care unit (ICU) of Oulu University Hospital due to acute necrotizing pancreatitis were retrospectively analyzed. All patients received standard surgical intensive care. RESULTS: Patients who died (n=14) had significantly higher APACHE II, SAPS II and Ranson scores at admission to the ICU and maximum SOFA score achieved during ICU stay than did the survivors. The non-survivors were hospitalized later from the time the symptoms were first manifest (5.3 vs. 2.4 days, P=0.051). Mechanical ventilation (P=0.002), surgical management (P=0.028), open packing surgical management (P=0.03), renal replacement therapy (P<0.001), use of inotropic drugs (P=0.012) and Staphylococcus epidermidis growth (P=0.029) in infected pancreatic tissue were all associated with mortality. CONCLUSIONS: In this study the time to hospitalization, severity of illness, intensity of care, and surgical management were associated with poor outcome. In addition, Staphylococcus epidermidis in pancreatic necrosis was associated with increased mortality.     

One-year results: palatal implants for the treatment of obstructive sleep apnea.

OBJECTIVE: To evaluate long-term effectiveness of palatal implants for treatment of mild to moderate obstructive sleep apnea (OSA). STUDY DESIGN: A prospective study of 26 referred patients with a pretreatment apnea-hypopnea index (AHI) of 10 to 30 and a body mass index of < or =30, representing an extended follow-up of a subset of 41 patients enrolled in previous short-term trials. RESULTS: Twenty-one of 26 patients (80.8%) experienced a decrease in AHI. Fifteen of 26 patients (57.7%) had a follow-up AHI <10 at 1 year, whereas 13 patients (50%) had a 50% or greater reduction to an AHI <10 at 1 year. Mean AHI was reduced from 16.5 +/- 4.5 at baseline to 12.5 +/- 10.5 at 3 months (P < 0.014) and to 12.3 +/- 12.7 at 1 year (P < 0.019). CONCLUSIONS: Patients initially responding to palatal implants with improved AHI maintained improvement through long-term follow-up at 1 year.     

Pelvic floor muscle strength and thickness in continent and incontinent nulliparous pregnant women

The aim of the study was to measure pelvic floor muscle function in continent and incontinent nulliparous pregnant women. The study group consisted of 103 nulliparous pregnant women at 20 weeks of pregnancy. Women reporting urinary incontinence once per week or more during the previous month were classified as incontinent. Function was measured by vaginal squeeze pressure (muscle strength) and increment in thickness of the superficial pelvic floor muscles (urogenital diaphragm) assessed by perineal ultrasound. Seventy-one women were classified as continent and 32 women as incontinent. Continent women had statistically significantly higher maximal vaginal squeeze pressure and increment in muscle thickness when compared with incontinent women. There was a strong correlation between measurements of vaginal squeeze pressure and perineal ultrasound measurements of increment in muscle thickness. This study demonstrates statistically significant differences in pelvic floor muscle function measured by strength and thickness in continent compared with incontinent nulliparous pregnant women. Editorial Comment: This study evaluated pelvic floor muscle function in 103 nulliparous continent and incontinent women at 18–20 weeks gestation. Pelvic floor muscle strength was assessed by measuring vaginal squeeze pressure, and thickness of the urogenital diaphragm during both relaxation and contraction was measured using perineal ultrasound. The authors found a statistically significant higher vaginal squeeze pressure and higher mean increment in muscle thickness in the continent compared with incontinent group as well as a strong correlation between pelvic floor muscle strength and increment in thickness. Although describing several benefits of ultrasonography in assessing pelvic floor muscles, the authors did acknowledge the difficulty in identifying and measuring these muscles, and the learning curve involved with perineal ultrasound. Another limitation was the subjective classification of continence status based on self-reported symptoms. The implication of low pelvic floor muscle strength and thickness as risk factors for the development of urinary incontinence is beyond the scope of this study.     

HRCT findings in the lungs of primary care patients with lower respiratory tract infection

Purpose: To survey the prevalence and type of lung patterns detectable at high-resolution CT (HRCT) in a primary care population seeking help for cough and fever.Material and Methods: The HRCT patterns of 103 patients obtained at the primary visit to a municipal health centre for cough and fever were evaluated. Forced expiratory examinations were obtained in 93 patients.Results: Lower respiratory tract infection (LRTI)-related findings (present at inclusion, healed at follow-up, not explained by any other factor) were seen in 19 patients (18.7%), of whom 11 also showed opacities, even though of lesser extent, at conventional chest radiography. The following patterns were found: ground-glass opacity (58%), discrete consolidations (52%), confluent consolidations (16%; 1 case with an air bronchogram), air space nodules (10%), peribronchovascular thickening (37%), tree-in-bud pattern (26%), free pleural fluid (5%), and septal thickening (5%). An expiratory mosaic pattern was seen in 19 (20%) out of 93 patients. In addition, lymph node enlargement (>1 cm) was recorded in 7 patients out of 103.Conclusion: HRCT is more sensitive than chest radiography in detecting LRTI-related lung lesions in a primary care population. The pattern typically comprises subtle scattered polymorphous opacities with varying attenuation affecting several lung segments. LRTI-related HRCT pattern deserves consideration as a differential diagnostic alternative in patients examined due to any lower respiratory tract symptoms.     

Transabdominal ultrasound measurement of pelvic floor muscle activity when activated directly or via a transversus abdominis muscle contraction

AIMS: The purpose of the present study was to compare the effectiveness of instruction to contract the pelvic floor muscles (PFM), the transversus abdominis (TrA), and the TrA + PFM visualized as displacement of the pelvic floor by ultrasound. MATERIALS AND METHODS: Twenty female physical therapists, mean age 41.1 years (range 26-56) participated in the study. A 3.5 MHz 35 mm curved linear array ultrasound transducer (Dornier Medtech) was placed in the mid-sagittal plane immediately suprapubically, angled at 15-30 degrees from the vertical depending on subcutaneous fat and anatomical variations, to image the pelvic floor. Six trials of three maneuvers in random order were performed: contraction of PFM, TrA, and TrA + PFM. RESULTS: In spite of correct contractions assessed by palpation and clinical observation, one subject demonstrated a downward movement of the pelvic floor during PFM contraction on ultrasound. Six subjects (30%) showed a downward movement during a TrA- contraction, and two during the combined TrA + PFM contraction. Instruction to contract PFM produced significantly greater mean displacement: 11.2 mm (95% CI 7.2-15.3) than TrA 4.3 mm (95% CI -0.2-8.8), P < 0.01, and combination: 8.5 mm (95% CI 5.2-12), P = 0.04. Hence, instruction of PFM contraction produced a 61.6% greater displacement of the pelvic floor in the correct direction than a TrA contraction. CONCLUSIONS: It is concluded that ultrasound is a more valid method than palpation and clinical observation to assess PFM function, and that instruction to contract the PFM produces a significantly more effective pelvic floor muscle contraction than instruction to perform a TrA contraction.     

Effect of test position on pelvic floor muscle assessment

The aims of this study were to analyse the effect of different body positions on pelvic floor muscle (PFM) assessment using digital muscle testing, manometry and transabdominal ultrasound. In addition, subject acceptance of each testing position was recorded. Subjects were 20 women's health physiotherapists. The testing protocol included the best of three maximum voluntary contractions tested in each of four positions (crook lying, supine, sitting and standing). Significant differences in muscle strength and subject acceptance between positions were found with each tool, most often between lying and upright positions. Digital muscle testing and vaginal squeeze-pressure scores were highest in the lying position, and vaginal resting pressure and transabdominal ultrasound scores were highest in the standing position. Subjects preferred the lying positions for internal examinations. The clinical significance of these differences and the reasons for these variations require further investigation.