Δευτέρα, 4 Ιουνίου 2018

A novel STK11 missense mutation (c.346G > T) causing Peutz–Jeghers syndrome in a Chinese male with a negative family history



from Gastroenterology via xlomafota13 on Inoreader https://ift.tt/2JryHh0
via IFTTT

Non-Cirrhotic Portal Hypertension: A possibly benign but complicated disease



from Gastroenterology via xlomafota13 on Inoreader https://ift.tt/2LmFplC
via IFTTT

Progressive multiple sclerosis patients have a higher burden of autonomic dysfunction compared to relapsing remitting phenotype

Multiple sclerosis (MS) is an idiopathic demyelinating disorder of the central nervous system. It most commonly affects young individuals, between 20 and 40 years-of-age and represents the leading cause of non-traumatic neurologic disability in young adults (Edmonds et al., 2010). Although the exact etiology is unknown, there is a complex interaction between several environmental factors and a distinct genetic susceptibility which results in demyelinating lesions, the pathological hallmark of MS (Compston and Coles, 2008).

from Physiology via xlomafota13 on Inoreader https://ift.tt/2JqH4JA
via IFTTT

Progressive multiple sclerosis patients have a higher burden of autonomic dysfunction compared to relapsing remitting phenotype

S13882457.gif

Publication date: Available online 4 June 2018
Source:Clinical Neurophysiology
Author(s): Ivan Adamec, Luka Crnošija, Anamari Junaković, Magdalena Krbot Skorić, Mario Habek
ObjectiveTo determine autonomic dysfunction (AD) differences in patients with relapsing remitting multiple sclerosis (pwRRMS) and progressive MS (pwPMS).MethodsComposite autonomic scoring scale (CASS) and heart rate variability (HRV) were performed in 40 pwRRMS and 30 pwPMS.ResultspwPMS had a significantly higher sudomotor index and total CASS score compared to pwRRMS (p<0.001 and p<0.001, respectively). Disease duration positively correlated with sudomotor index and total CASS (rs=0.409, p<0.001 and rs=0.472, p<0.001, respectively), while the Expanded Disability Status Scale (EDSS) positively correlated with sudomotor index and total CASS (rs=0.411, p<0.001 and rs=0.402, p=0.001, respectively) in all patients. Type of multiple sclerosis (pwRRMS or pwPMS) corrected for age, sex and disease duration, was a statistically significant predictor of CASS value (B=1.215, p=0.019). Compared to pwRRMS, pwPMS had a significantly lower standard deviation of NN intervals (SDNN), low frequency (LF), and high frequency (HF), during both the supine and tilt-up phases (all p-values <0.006). pwPMS had a significantly lower LF/HF (p=0.008) during tilt-up.ConclusionThere is a significant difference in autonomic function in pwRRMS and pwPMS; with pwPMS having a higher burden of AD, which is particularly evident for sweating dysfunction.SignificanceFurther research is needed to establish whether parasympathetic and sudomotor dysfunction may serve as markers of progressive MS.



from Physiology via xlomafota13 on Inoreader https://ift.tt/2Je4sqf
via IFTTT

The role of endoscopic treatment of pancreatic duct disruption in patients with walled-off pancreatic necrosis

Abstract

Background

The place of endoscopic techniques in the treatment of main pancreatic duct (MPD) disruption arising in the course of acute necrotizing pancreatitis (ANP) remains unclear. The aim of this study was to describe the findings of endoscopic retrograde pancreatography (ERP) in patients with walled-off necrosis (WON). It was attempted to evaluate the role of endoscopic treatment of pancreatic duct disruption in patients with WON.

Methods

The retrospective analysis of results and complications with particular emphasis to all ERP procedures in the group of 226 patients was conducted, which underwent endoscopic treatment of symptomatic WON between years 2001 and 2016 in the Department of Gastroenterology and Hepatology of Medical University of Gdańsk.

Results

ERP was performed in 204/226 (90.27%) patients. Partial and complete disruption of the MPD were identified in 103 (50.49%) and 63 (30.89%) out of 204 patients, respectively. Endoscopic treatment was used in all 166 patients with MPD disruption. The success of endoscopic treatment of MPD disruption was achieved in 138/161 (85.71%) patients with WON. The therapeutic success of WON endotherapy was achieved in 214/226 (94.69%) patients. The mean follow-up duration was 56 (SD = 37.06) [range 14–158] months. Long-term success of treatment of WON was achieved in 182/226 (80.53%) patients.

Conclusions

MPD disruption occurs in the majority of patients with WON. Partial disruption of the MPD is more frequent than complete disruption of the duct. This study conducted on a large group of patients demonstrated that prosthesis insertion into the MPD in patients with disruption of the MPD in the course of ANP is one of the key elements in endoscopic treatment of WON. Passive transpapillary drainage is an effective method of treating MPD disruptions, which improves long-term outcomes of endoscopic treatment in patients with WON.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2kLzwD6
via IFTTT

Laparoscopic common bile duct exploration in patients with previous upper abdominal surgery

Abstract

Background

Although patients with previous upper abdominal surgery are no longer considered as a contraindication in laparoscopic surgery, laparoscopic common bile duct exploration (LCBDE) for these patients is still controversial. The aim of this study was to evaluate the safety and effectiveness of LCBDE for patients with previous upper abdominal surgery.

Methods

Two hundred and seventeen patients with common bile duct stones who underwent LCBDE in our institution from January 2010 to September 2017 were enrolled in the retrospective study. They were divided into two groups: group A, with previous upper abdominal surgery (n = 50) and group B, without previous upper abdominal surgery (n = 167). Patients' demographic, intraoperative, and postoperative outcomes were retrospectively analyzed.

Results

Group A exhibited a longer operative time compared to group B (179.7 ± 61.5 vs. 156.0 ± 46.8 min, p = 0.014). There was no significant difference in intraoperative blood loss (123.9 ± 99.5 vs. 99.5 ± 84.7 mL, p = 0.087), postoperative hospital stay (7.4 ± 2.6 vs. 6.8 ± 2.3 d, p = 0.193), and overall complication rate (8.0 vs. 5.4%, p = 0.732) between the two groups. There was no mortality in both groups. The initial stone clearance rate showed no significant difference between the two groups (98.0 vs. 98.2%, p = 1.000), and the final stone clearance rate was 100% in both groups (p = 1.000). The stone recurrence rate had no significant difference between the two groups (2.0 vs. 2.4%, p = 1.000). The conversion rate was comparable between group A and group B (6.0 vs. 4.8%, p = 0.718).

Conclusions

LCBDE is a safe and feasible procedure for patients with previous upper abdominal surgery. The keys of this procedure are carefully separating the adhesions and clearly exposing the common bile duct, and using a variety of methods to remove the stones.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2HjNOUk
via IFTTT

Additional value of EUS in oesophageal cancer patients staged N0 on PET/CT: validation of a prognostic model

Abstract

Background

Lymph node metastases are a major prognostic indicator in oesophageal cancer. Radiological staging largely influences treatment decisions and is becoming more reliant on PET and CT. However, the sensitivity of these modalities is suboptimal and is known to under-stage disease. The primary aim of this study was to validate a published prognostic model in oesophageal cancer patients staged N0 with PET/CT, which showed that EUS nodal status was an independent predictor of survival. The secondary aim was to assess the prognostic significance of pathological lymph node metastases in this cohort.

Methods

An independent validation cohort included 139 consecutive patients from a regional upper gastrointestinal cancer network staged N0 with PET/CT between 1st January 2013 and 31st June 2015. Replicating the original study, two Cox regression models were produced: one included EUS T-stage and EUS N-stage, and one included EUS T-stage and EUS N0 versus N+. The primary outcome of the prognostic model was overall survival (OS). Kaplan–Meier analysis assessed differences in OS between pathological node-negative (pN0) and node-positive (pN+) groups. A p value of < 0.05 was considered statistically significant.

Results

The mean OS of the validation cohort was 29.8 months (95% CI 27.1–35.2). EUS T-stage was significantly and independently associated with OS in both models (p = 0.011 and p = 0.012, respectively). EUS N-stage and EUS N0 versus N+ were not significantly associated with OS (p = 0.553 and p = 0.359, respectively). There was a significant difference in OS between pN0 and pN+ groups (χ2 13.315, df 1, p < 0.001).

Conclusion

Lymph node metastases have a significant detrimental effect on OS. This validation study did not replicate the results of the developed prognostic model but the continued benefit of EUS in patients staged N0 with PET/CT was demonstrated. EUS remains a valuable component of a multi-modality approach to oesophageal cancer staging.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2kKQpOe
via IFTTT

Analysis of laparoscopic laser liver resection in standardized porcine model

Abstract

Background

Hepatocellular carcinoma is a highly prevalent and lethal primary neoplasia of the liver and metastases of other malignancies affect most frequently the liver. Minimally invasive surgical approach for liver resections is advancing. Dissection of liver parenchyma by laparoscopic technique remains challenging and new technologies are in need. Therefore, we asked whether it is feasible to dissect liver tissue comparably in terms of speed and hemostasis with a non-contact 1.9-µm cw-laser device and whether there are differences in the postoperative healing process compared to a gold standard device (ultrasound aspirator) in an experimental model.

Methods

Laparoscopic laser and ultrasound aspirator standardized partial liver resections were performed in seven pigs. Resection time, hemostasis time, and blood loss were evaluated. After at least 10 days, representative specimen of the resection areas was collected via re-laparoscopy and biopsy and side effects like hematoma, abscess, or bilioma were noted. Histologically, coagulation necrosis margin, granulation tissue zone, tissue fibrosis, and giant cell count were analyzed.

Results

Laparoscopic laser liver resection was three times faster compared to the laparoscopic ultrasound aspirator. Blood loss was equal in both groups. No side effects like hematoma or bilioma occurred. Histologically, specimen showed the same expansion of coagulation necrosis zone and granulation tissue. Fibrotic scar could be determined in three cases in both groups, respectively. However, giant cell count was significant higher in the laser resection group.

Conclusions

The 1.9-µm cw-laser device enables a safe and fast liver resection in an experimental pig model compared to a gold standard (ultrasound aspirator) laparoscopic liver resection method. Wound healing is not interfered by laser liver resection.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2HgtNy9
via IFTTT

Image-guided video-assisted thoracoscopic small lung tumor resection using near-infrared marking

Abstract

Background

Localization of non-visible, non-palpable small pulmonary nodules during video-assisted thoracoscopic surgery (VATS) remains challenging. We sought to investigate the feasibility and safety of image-guided video-assisted thoracoscopic surgery (iVATS) with near-infrared (NIR) marking in a hybrid operating room (OR).

Methods

Both localization and surgery were performed by a single team of thoracic surgeons. Diluted indocyanine green (ICG; quantity: 0.3–0.5 mL; dye concentration: 0.125 mg/mL) was injected percutaneously to pinpoint the tumor's location under cone beam computed tomography (CBCT) guidance using a laser-guided navigation system. Real-time fluorescence images were intraoperatively obtained using a NIR thoracoscopic camera to guide subsequent resection.

Results

Between March and December 2017, 26 patients underwent NIR marking of small pulmonary nodules for iVATS. The median tumor size was 7 mm (interquartile range [IQR] 5.3–10.8 mm), whereas their median distance from the pleural surface was 5 mm (IQR 0.3–10.5 mm). Seven nodules (35%) were solid, whereas 17 (65%) were ground-glass opacities. All lesions were identifiable on intraoperative CBCT. The median time required for NIR localization was 13 min. An NIR(+) "tattoo" was identified in all cases, and no intraoperative conversion to thoracotomy occurred. The final pathological diagnoses were primary lung cancer (n = 11), metastatic cancer (n = 6), and benign lung tumor (n = 9). Adverse events were not observed, and the median length of post-operative stay was 4 days (IQR 3–4 days).

Conclusions

Our data show that iVATS with NIR marking is useful, has no adverse effects, and can successfully localize difficult-to-identify small pulmonary nodules.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2kNCEP5
via IFTTT

Prospective study of the effect of topical application of Mitomycin C in refractory pediatric caustic esophageal strictures

Abstract

Background

Esophageal strictures resulting from caustic ingestion in children are usually difficult to be managed, and surgical replacement is usually required for cases refractory to frequent dilatation sessions. Topical Mitomycin C (MMC) has been recently used in the management of resistant strictures. We evaluated the efficacy of MMC application in treatment of long refractory caustic esophageal strictures.

Methods

This prospective study included 120 patients of both sexes with refractory caustic long esophageal strictures (> 3 cm in length). All patients were randomly divided into two equal groups using the research randomizer program (1:1 randomization), group I underwent endoscopic dilatation therapy only and group II underwent dilatation with topical application of MMC. Follow-up was done regularly by assessing the dysphagia score and patients were evaluated after 6 months of management. The procedure was repeated four times with 2-week intervals. Complete relieve of symptoms (dysphagia score = 0) was assessed after the follow-up period.

Results

The complete cure was detected in 81.6% of patients in the MMC group compared to only 40% in the first group, p-value < 0.0001. During the follow-up, the average sessions of dilatation needed in group II were 3.25 ± 2.78 compared to 6.25 ± 1.74 sessions in group I (p < 0.001). The mean cost of sessions in patients who showed symptomatic and endoscopic improvement was significantly lower in group II (272.2 ± 51 US$) when compared to group I (404 ± SD 55.7 US$).

Conclusions

Cure rate was double in the MMC group. MMC application significantly improved symptoms and reduced both the number and frequency of dilatations to alleviate dysphagia in patients with refractory caustic esophageal strictures and hence reduced the cost of treatment.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2Hm3jLw
via IFTTT

Efficacy of ultrasound-guided transversus abdominis plane (TAP) block for postoperative analgesia in laparoscopic gastric sleeve resection: a randomized single blinded case control study

Abstract

Background

Pain following bariatric surgery can be quite troublesome and prolongs recovery. Transversus abdominis plane (TAP) block is a new regional anesthetic technique to reduce postoperative pain and is an important part of current analgesic regimen for many abdominal surgeries. The primary objective of our study was to assess the efficacy of the TAP block in controlling postoperative pain in laparoscopic sleeve gastrectomy. Secondary outcomes assessed in this study were postoperative nausea and vomiting (PONV), time to ambulate, readiness for discharge, and whether it leads to improved patient satisfaction.

Methods

This is a prospective single blind randomized controlled study. A total of 60 patients were included in the study. Patients were allocated in two groups, using a computer generated randomization sequence using http://www.randomization.com. Test group included 30 patients who received Ultrasound-guided transversus abdominis plane (USG-TAP) block along with systemic analgesia and the Control group included 30 patients who received only systemic analgesia. Postoperatively patients were evaluated for pain and satisfaction using VAS scores and 'Capuzzo' satisfaction score, respectively.

Results

Sixty patients were enrolled in the study after fulfilling the eligibility criteria. No patient was lost to follow-up. The difference of VAS scores between test (TAP) and control (Non-TAP) was statistically significant both at rest and on movement. The patient satisfaction score in TAP group was higher than the control group (p value < 0.001). The patients who received TAP block showed earlier readiness for discharge, early ambulation, early resumption of bowel activity, and decreased incidence of PONV as compared to the non-TAP group.

Conclusion

USG-guided TAP block is a feasible, minimally invasive technique and can be a part of an effective multimodal analgesia in morbidly obese patients undergoing bariatric surgery. Limitations of this study would be the small sample size and the study being Single-blinded.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2svE98T
via IFTTT

Structured assessment of laparoscopic camera navigation skills: the SALAS score

Abstract

Background

Tools are needed to assess laparoscopic camera navigation (LCN) in the operating room. Here, we aimed to develop an objective rating scale for LCN.

Study design

We defined the following key aspects of LCN: operational field centering, correct angle of the horizon, correct instrument visualization, verbal commands from the operating surgeon, and manual corrections from the operating surgeon. We then developed a score based on intraoperative error evaluation from intraoperative recordings of 80 procedures. Finally, the newly developed score was validated by four different raters using video-based analysis of 20 elective laparoscopic cholecystectomies.

Results

We developed and validated a tool for the structured assessment of laparoscopic assistant skills (SALAS). This score showed good internal consistency, with a Cronbach's alpha of > 0.7. Intraclass correlation revealed a low interrater variability (ICC 0.866) for the total score. Comparison of experienced and inexperienced camera assistants revealed significantly better SALAS scores for experienced assistants (p < 0.05).

Conclusion

Our present results show that SALAS score is valid, reliable, and practicable. This score can be used for future investigations of camera navigation efficiency and training.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2sFpmI0
via IFTTT

Cost-effectiveness analysis of laparoscopic versus open surgery in colon cancer

Abstract

Background

Few economic evaluations have assessed laparoscopy for colon cancer. This study aimed to compare the cost-effectiveness of laparoscopic and open surgery for the treatment of colon cancer.

Method

A cost-effectiveness analysis was performed comparing two groups of patients treated according to standard clinical practice (REDISSEC-CARESS/CCR cohort) by laparoscopic or open surgery. Data were collected from health records on clinical characteristics and resource use over 2 years after surgery. To calculate the incremental cost-effectiveness ratio, costs and quality-adjusted life years (QALYs) were obtained for each patient. Clinical heterogeneity was addressed using propensity score and joint multivariable analysis (seemingly unrelated regression) that included interactions between TNM stage, age, and surgical procedure to perform subgroup analysis.

Results

The sample was composed of 1591 patients, 963 who underwent laparoscopy and 628 open surgery. Using propensity score and regression analysis, we found that laparoscopy was associated with more QALYs and less resource use than open surgery (0.0163 QALYs, 95% CI 0.0114–0.0212; and − €3461, 95% CI − 3337 to − 3586). Costs were lower for laparoscopy in all subgroups. In the subgroups younger than 80 years old, utility was higher in patients who underwent laparoscopy. Nevertheless, open surgery had better outcomes in older patients in stages I–II (0.0618 QALYs) and IV (0.5090 QALYs).

Conclusion

Overall, laparoscopy appears to be dominant, resulting in more QALYs and lower costs. Nevertheless, while laparoscopy required fewer resources in all subgroups, outcomes may be negatively affected in elderly patients, representing an opportunity for shared decision making between surgeons and patients.

ClinicalTrials.gov Identifier: NCT02488161



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2swZi2l
via IFTTT

Comparison of outcomes following laparoscopic and open treatment of emergent small bowel obstruction: an 11-year analysis of ACS NSQIP

Abstract

Background

Small bowel obstruction (SBO) continues to be a common indication for acute care surgery. While open procedures are still widely used for treatment, laparoscopic procedures may have important advantages in certain patient populations. We aim to analyze differences in outcomes between the two for treatment of bowel obstruction.

Methods

The American College of Surgeons National Surgical Quality Improvement Program was used to find patients that underwent emergent or non-elective surgery for SBO. Propensity matching was used to create comparable groups. Logistic regression was used to assess differences in the primary outcome of interest, return to operating room, and morbidity and mortality outcomes. Logistic regression was also used to assess the contribution of various preoperative demographic and comorbidity characteristics to 30-day mortality.

Results

A total of 24,028 patients underwent surgery for SBO from 2005 to 2011. Of those, 3391 were laparoscopic. Propensity matching resulted in 6782 matched patients. Laparoscopic cases had significantly decreased odds of experiencing any morbidity and wound complications compared to open cases in bowel-resection and adhesiolysis-only cases. There was no significant difference found for odds of returning to operating room. Laparoscopic cases resulted in significantly shorter hospital stays than open cases (7.18 vs.10.84 days, p < 0.0001). Increasing age, American Society of Anesthesiologists class greater than three, and the presence of respiratory comorbidities resulted in increased odds of mortality. Underweight body mass index (BMI) (< 18.5) increased odds of mortality while greater than normal BMI (> 25) decreased odds of mortality.

Conclusions

Analysis of emergent SBO cases between 2005 and 2015 demonstrates that laparoscopy is not utilized as often as open approaches in surgical treatment. Laparoscopic surgery resulted in reduced postoperative morbidity and significantly shorter hospital stays compared to open intervention and was not associated with significant differences in odds of reoperation compared to open surgery.



from Endoscopy via xlomafota13 on Inoreader https://ift.tt/2HkOcBY
via IFTTT

A novel sensor-based assessment of lower limb spasticity in children with cerebral palsy

To provide effective interventions for spasticity, accurate and reliable spasticity assessment is essential. For the assessment, the Modified Tardieu Scale (MTS) has been widely used owing to its simplicity an...

from Rehabilitation via xlomafota13 on Inoreader https://ift.tt/2kOGDus
via IFTTT

Exercise-Derived Microvesicles: A Review of the Literature

Abstract

Initially suggested as simple cell debris, cell-derived microvesicles (MVs) have now gained acceptance as recognized players in cellular communication and physiology. Shed by most, and perhaps all, human cells, these tiny lipid-membrane vesicles carry bioactive agents, such as proteins, lipids and microRNA from their cell source, and are produced under orchestrated events in response to a myriad of stimuli. Physical exercise introduces systemic physiological challenges capable of acutely disrupting cell homeostasis and stimulating the release of MVs into the circulation. The novel and promising field of exercise-derived MVs is expanding quickly, and the following work provides a review of the influence of exercise on circulating MVs, considering both acute and chronic aspects of exercise and training. Potential effects of the MV response to exercise are highlighted and future directions suggested as exercise and sports sciences extend the realm of extracellular vesicles.



from Sports Medicine via xlomafota13 on Inoreader https://ift.tt/2sFqxqG
via IFTTT

What Approaches are Most Effective at Addressing Micronutrient Deficiency in Children 0–5 Years? A Review of Systematic Reviews

Abstract

Introduction Even though micronutrient deficiency is still a major public health problem, it is still unclear which interventions are most effective in improving micronutrient status. This review therefore aims to summarize the evidence published in systematic reviews on intervention strategies that aim at improving micronutrient status in children under the age of five. Methods We searched the literature and included systematic reviews that reported on micronutrient status as a primary outcome for children of 0–5 years old, had a focus on low or middle income countries. Subsequently, papers were reviewed and selected by two authors. Results We included 4235 reviews in this systematic review. We found that (single or multiple) micronutrient deficiencies in pre-school children improved after providing (single or multiple) micronutrients. However home fortification did not always lead to significant increase in serum vitamin A, serum ferritin, hemoglobin or zinc. Commercial fortification did improve iron status. Cord clamping reduced the risk of anemia in infants up to 6 months and, in helminth endemic areas, anthelminthic treatment increased serum ferritin levels, hemoglobin and improved height for age z-scores. Anti-malaria treatment improved ferritin levels. Discussion Based on our results the clearest recommendations are: delayed cord clamping is an effective intervention for reducing anemia in early life. In helminth endemic areas iron status can be improved by anthelminthic treatment. Anti-malaria treatment can improve ferritin. In deficient populations, single iron, vitamin A and multimicronutrient supplementation can improve iron, vitamin A and multimicronutrient status respectively. While the impact of home-fortification on multimicronutrient status remains questionable, commercial iron fortification may improve iron status.



from Health via xlomafota13 on Inoreader https://ift.tt/2LV94mY
via IFTTT

Dental Caries Experience and Utilization of Oral Health Services Among Tibetan Refugee-Background Children in Paonta Sahib, Himachal Pradesh, India

Abstract

The study was done to describe the dental caries experience and dental care utilization among Tibetan refugee-background children in Paonta Sahib, India. The study was conducted on 254 school children in a Tibetan settlement in Paonta Sahib. Examination was done as per World Health Organization Oral Health Assessment criteria (2013). Data on dental services utilization was obtained from the parents of children using a structured questionnaire. Oral examination of 254 school children aged 6–18 years revealed an overall dental caries prevalence of 79.5%. The dental caries experience was greater in the mixed dentition (84%) than secondary dentition (77.3%). The mean DMFT was associated with sex and dental visiting patterns. About 60% children had never visited a dentist before. The main reason for dental visit was tooth removal (43%). The prevalence of dental caries among Tibetan refugee-background school children was high and utilization of dental care was low. A comprehensive oral health program focusing on preventive care and oral health education is recommended.



from Health via xlomafota13 on Inoreader https://ift.tt/2xGrLYp
via IFTTT

The giant butterfly-moth Paysandisia archon has spectrally rich apposition eyes with unique light-dependent photoreceptor dynamics

Abstract

The palm borer moth Paysandisia archon (Burmeister, 1880) (fam. Castniidae) is a large, diurnally active palm pest. Its compound eyes consist of ~ 20,000 ommatidia and have apposition optics with interommatidial angles below 1°. The ommatidia contain nine photoreceptor cells and appear structurally similar to those in nymphalid butterflies. Two morphological ommatidial types were identified. Using the butterfly numbering scheme, in type I ommatidia, the distal rhabdom consists exclusively of the rhabdomeres of photoreceptors R1–2; the medial rhabdom has contributions from R1–8. The rhabdom in type II ommatidia is distally split into two sub-rhabdoms, with contributions from photoreceptors R2, R3, R5, R6 and R1, R4, R7, R8, respectively; medially, only R3–8 and not R1–2 contribute to the fused rhabdom. In both types, the pigmented bilobed photoreceptors R9 contribute to the rhabdom basally. Their nuclei reside in one of the lobes. Upon light adaptation, in both ommatidial types, the rhabdoms secede from the crystalline cones and pigment granules invade the gap. Intracellular recordings identified four photoreceptor classes with peak sensitivities in the ultraviolet, blue, green and orange wavelength regions (at 360, 465, 550, 580 nm, respectively). We discuss the eye morphology and optics, the photoreceptor spectral sensitivities, and the adaptation to daytime activity from a phylogenetic perspective.



from Physiology via xlomafota13 on Inoreader https://ift.tt/2LTTc4a
via IFTTT