A bias‐free two‐alternative forced choice procedure to examine intersensory illusions applied to the ventriloquist effect by flashes and averted eye‐gazes

We compared with a new psychophysical method whether flashes and averted eye‐gazes of a cartoon face induce a ventriloquist illusion (an illusory shift of the apparent location of a sound by a visual distracter). With standard psychophysical procedures that measure a direct ventriloquist effect and a ventriloquist aftereffect, we found in human subjects that both types of stimuli induced an illusory shift of sound location. These traditional methods, though, are probably contaminated by response strategies. We therefore developed a new two‐alternative forced choice procedure that allows measuring the strength of an intersensory illusion in a bias‐free way. With this new procedure we found that only flashes, but not averted eye‐gazes, induced an illusory shift in sound location. This difference between flashes and eye‐gazes was validated in an EEG study in which again only flashes illusorily shifted the apparent location of a sound thereby evoking a mismatch negativity response. These results are important because they highlight that commonly used measures of multisensory illusions are contaminated while there is an easy yet stringent way to measure the strength of an illusion in a bias‐free way.     

Excisional biopsy of suspected benign soft tissue tumors of the upper extremity: correlation between preoperative diagnosis and actual pathology

Background

Tumors of the upper extremity are common and mostly benign. However, the prevalence of discordant diagnosis of a solid hand tumor is less studied. The objectives of this retrospective study were (1) to determine the proportion of patients with a different (discrepant or discordant) pathological diagnosis compared to the preoperative diagnosis, (2) to determine the prevalence of the types of pathologies encountered at excisional biopsy for suspected benign tumors, and (3) to determine the types of tumors diagnosed when the surgeon does not make a preoperative diagnosis.

Methods

One hundred and eighty-two suspected benign soft tissue tumors of the upper extremity with a preoperative diagnosis other than ganglion cyst were excised by one of three surgeons over a 10-year period. A preoperative diagnosis was applied for 125 tumors. No preoperative imaging was used.

Results

Only 26 of the 125 tumors (21 %) with a preoperative diagnosis were discrepant. The tumors that were most likely to have a discrepant diagnosis were vascular tumors (32 %) and other less common benign tumors (33 %). Among the entire cohort of 182 tumors, lipomas (19 %), giant cell tumors of tendon sheath (GCTTS; 19 %), and vascular tumors (16 %) were the most frequent pathological diagnoses. Among the 57 tumors that did not have a preoperative diagnosis, most were vascular tumors (23 %), fibromas (14 %), and GCTTS (11 %). One tumor without a preoperative diagnosis was a malignant tumor, but we consider this unusual and possibly spurious.

Conclusions

A hand surgeon’s preoperative diagnosis without imaging is usually correct prior to excision of a mass in the hand. Discrepant diagnoses are usually benign and do not alter treatment. Level of evidence: Prognostic II     

Hospital variation in combined liver resection and thermal ablation for colorectal liver metastases and impact on short-term postoperative outcomes: a nationwide population-based study

BackgroundCombining resection and thermal ablation can improve short-term postoperative outcomes in patients with colorectal liver metastases (CRLM). This study assessed nationwide hospital variation and short-term postoperative outcomes after combined resection and ablation.MethodsIn this population-based study, all CRLM patients who underwent resection in the Netherlands between 2014 and 2018 were included. After propensity score matching for age, ASA-score, Charlson-score, diameter of largest CRLM, number of CRLM and earlier resection, postoperative outcomes were compared. Postoperative complicated course (PCC) was defined as discharge after 14 days or a major complication or death within 30 days of surgery.ResultsOf 4639 included patients, 3697 (80%) underwent resection and 942 (20%) resection and ablation. Unadjusted percentage of patients who underwent resection and ablation per hospital ranged between 4 and 44%. Hospital variation persisted after case-mix correction. After matching, 734 patients remained in each group. Hospital stay (median 6 vs. 7 days, p = 0.011), PCC (11% vs. 14.7%, p = 0.043) and 30-day mortality (0.7% vs. 2.3%, p = 0.018) were lower in the resection and ablation group. Differences faded in multivariable logistic regression due to inclusion of major hepatectomy.ConclusionSignificant hospital variation was observed in the Netherlands. Short-term postoperative outcomes were better after combined resection and ablation, attributed to avoiding complications associated with major hepatectomy.     

Short-term dietary adjustment with a hydrolyzed casein-based diet postpones diabetes development in the diabetes-prone BB rat

From earlier studies it appears that weaning associated changes in the animal's physiology and that of the pancreas in particular, render diabetes-prone Bio-Breeding (DP-BB) rats susceptible to the induction and development of insulin-dependent diabetes mellitus (IDDM). In this study we tested whether a short-term dietary adjustment at weaning would influence the development of diabetes later in life. For this purpose a diet in which the protein source was replaced with hydrolyzed casein (HC) was given to the rats from weaning to 60 days of age and from weaning to 130 days of age. The control group received the cereal-based standard diet throughout the experiment. The short-term dietary adjustment resulted in a significant delay of diabetes development. The rats fed the HC diet from weaning to 130 days of age showed a lower incidence of diabetes at 130 days of age. No differences were seen in the histological insulitis scores between the rats of the different treatment groups. Interestingly, when testing (mucosal) immune functions of short-term HC-fed rats, their mesenteric lymph node cells (MLNC) showed increased interferon-gamma (IFN-gamma) and reduced interleukin-10 (IL-10) production after in vitro stimulation. These results demonstrate that short-term dietary adjustments at a young age can influence the course of diabetes later in life. The shift in cytokine profile of MLNC of the HC-fed rats suggests that mechanisms involved can be at the level of both the (mucosal) immune system and the beta cell.     

Role of wastewater irrigation in mosquito breeding in south Punjab,Pakistan

Mosquito breeding within the wastewater irrigation system around the town of Haroonabad in the southern Punjab, Pakistan, was studied from July to September 2000 as part of a wider study of the costs and benefits of wastewater use in agriculture. The objective of this study was to assess the vector-borne human disease risks associated with mosquito species utilizing wastewater for breeding. Mosquito larvae were collected on a fortnightly basis from components of the wastewater disposal system and irrigated sites. In total, 133 samples were collected, about equally divided between agricultural sites and the wastewater disposal system. Overall, 17.3% of the samples were positive for Anopheles, 12.0% for Culex and 15.0% for Aedes. Four anopheline species, viz, Anopheles stephensi (84.3% of total anophelines), An. subpictus (11.8%), An. culicifacies (2.0%) and An. pulcherrimus (0.2%) were present, as were two species of Culex, viz, Cx. quinquefasciatus (66.5% of culicines) and Cx. tritaeniorhynchus (20.1%). Aedes were not identified to species level. The occurrence of different species was linked to particular habitats and habitat characteristics such as physical water condition, chemical water quality and the presence of fauna and flora. Anophelines and Aedes mosquitos were mainly collected during the month of July, while Culex were collected in September. The prevalence of established vectors of human diseases such as An. stephensi (malaria), Cx. tritaeniorhynchus (West Nile fever, Japanese encephalitis) and Cx. quinquefasciatus (Bancroftian filariasis, West Nile fever) in the wastewater system indicated that such habitats could contribute to vector-borne disease risks for human communities that are dependent upon wastewater use for their livelihoods. Wastewater disposal and irrigation systems provide a perennial source of water for vector mosquitos in semi-arid countries like Pakistan. Vector mosquitos exploit these sites if alternative breeding sites with better biological, physical, and chemical conditions are not abundant.