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Marco Carifi,1 Domenico Napolitano,1 Morando Morandi,1 Danilo Dall’Olio2 1Department of Otolaryngology, Azienda Ospedaliera di Rilievo Nazionale A Cardarelli, Naples, 2Department of Otolaryngology, Ospedale Maggiore CA Pizzardi, Bologna, Italy Abstract: Although recurrent respiratory papillomatosis is a benign disease of the upper aerodigestive tract caused by infection with human papillomavirus, the disease process is unpredictable, ranging from mild disease and spontaneous remission to an aggressive disease with pulmonary spread and requirement for frequent surgical debulking procedures. It can present a protracted clinical course and cause potentially life-threatening compromise of the airways. Over recent decades, a number of alternative medical therapies to standard surgical treatment have been investigated, with modest outcomes overall. Currently, some additional therapies are being explored, together with novel surgical instrumentation that can help to avoid inevitable long-term stenotic complications, ultimately affecting quality of life. Hopefully, clinicians might soon be able to significantly improve the quality of treatment and outcomes for patients affected with recurrent respiratory papillomatosis, with human papillomavirus vaccination having a potentially important role. Keywords: recurrent respiratory papillomatosis, laryngeal papillomatosis, adjuvant, cidofovir, bevacizumab, photodynamic therapy, microdebrider, angiolytic laser, celecoxib, HspE7

Inflammatory bowel diseases (IBDs), encompassing Crohn's disease and ulcerative colitis, are complex chronic disorders characterized by an intricate interplay between genetic predisposition, immune dysregulation, gut microbiota alterations, and environmental exposures. This review aims to synthesize recent advances in IBD pathogenesis, exploring key mechanisms and potential avenues for prevention and personalized therapy. A comprehensive literature search was conducted across major bibliographic databases, selecting the most recent and impactful studies on IBD pathogenesis. The review integrates findings from multi-omics analyses, single-cell transcriptomics, and longitudinal cohort studies, focusing on immune regulation, gut microbiota dynamics, and environmental factors influencing disease onset and progression. Immune dysregulation, including macrophage polarization (M1 vs. M2) and Th17 activation, emerges as a cornerstone of IBD pathogenesis. Dysbiosis, as a result of reduced alpha and beta diversity and overgrowth of harmful taxa, is one of the main contributing factors in causing inflammation in IBD. Environmental factors, including air and water pollutants, maternal smoking, and antibiotic exposure during pregnancy and infancy, significantly modulate IBD risk through epigenetic and microbiota-mediated mechanisms. While recent advances have supported the development of new therapeutic strategies, deeply understanding the complex dynamics of IBD pathogenesis remains challenging. Future efforts should aim to reduce the burden of disease with precise, personalized treatments and lower the incidence of IBD through early-life prevention and targeted interventions addressing modifiable risk factors.

Background: Ustekinumab (UST) is an interleukin-12/interleukin-23 receptor antagonist approved for the treatment of Crohn's disease (CD). Only limited real-life data on the long-term outcomes of CD patients treated with UST are available. This study assessed UST's long-term effectiveness and safety in a large population-based cohort of moderate to severe CD patients. Methods: This was a multicenter, retrospective, observational cohort study that included both naïve and biologic-experienced patients treated with UST who achieved clinical remission or clinical response after at least one year of treatment. Clinical activity was scored according to the Harvey-Bradshaw Index (HBI). The primary endpoints were the maintenance or achievement of clinical remission after a further 12-month period of treatment, defined as an HBI of ≤5, and safety. Other endpoints included steroid-free remission, mucosal healing (MH), steroid discontinuation, and the need for treatment optimization during the follow-up. Results: Out of 562 CD patients, after an overall 24-month follow-up, clinical remission was present in 450 (80.0%) patients, and at 12 months, clinical remission was observed in 417/437 (95.4%) patients; 33/125 (26.4%) showed clinical response at 12 months ( p = 0.000). A total of 38/103 (36.9%) patients achieved MH. Only 2.1% (12/562), 3% (17/562), and 1.1% (6/562) of patients required surgery, optimization, and re-induction, respectively. Adverse events occurred in eight patients (1.42%). According to a multivariate analysis, the only predictor of long-term remission was the presence of remission at the 12-month follow-up ( p = 0.000). Conclusions : Long-term treatment with UST presents good efficacy and safety profiles in CD patients, especially for patients who achieve remission after one year.

Introduction: Supporting patient self-care and the contribution of their caregivers is crucial in chronic illness care. Inflammatory bowel disease (IBD) is a chronic condition whose prevalence is expected to double, especially in Western countries. IBD symptoms can negatively impact patients' well-being, causing high anxiety, depression, stress and reduced quality of life. These symptoms also affect the health of family members and friends, who often take on caregiving roles during exacerbations. Knowledge about self-care in IBD (IBD-SELF) is limited, and few studies have explored this context. This paper outlines a research protocol for a multicentre longitudinal study to investigate patient self-care and caregiver contributions to IBD-SELF., Methods and Analysis: A sample of 250 consecutive patients diagnosed with IBD and their caregivers will be recruited from 9 dedicated IBD units in northern, central and southern Italy during outpatient visits. Data collection will occur at baseline, 6 and 12 months after enrolment. Multivariable regressions, path analyses and structural equation models will identify predictors (eg, health literacy, caregiver burden and depression) and outcomes (use of healthcare services, disease severity and quality of life) of self-care and caregiver contributions. Dyadic analyses will control for the interdependence of dyad members., Ethics and Dissemination: Ethical approval was obtained from the Territorial Ethics Committee (Lazio 3) N. 0023486/23 and registered on ClinicalTrials.gov (Identifier number: NCT06015789). This study will enhance our understanding of the self-care process in the patient-caregiver dyad in IBD, aiding the design of future educational interventions and promoting greater patient and caregiver involvement in the care pathway., Trial Registration Number: ClinicalTrials.gov: NCT06015789., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Objectives: Acute kidney injury (AKI) remains a significant complication following major cardiac surgery. Marinobufagenin (MBG), a cardiotonic steroid involved in sodium balance and blood pressure regulation, has been linked to organ damage after ischemia-reperfusion events. This pilot, prospective study investigates the utility of circulating MBG to improve AKI risk assessment in cardiac surgery patients as a stand-alone biomarker and after inclusion in a validated risk model (STS-AKI score). Materials and Methods: We included 45 patients undergoing elective cardiac surgery. The MBG levels were measured preoperatively and at 4, 8, and 12 h post-surgery. The AKI was defined according to the KDIGO guidelines. Statistical analyses assessed the diagnostic and prognostic utility of MBG and its integration with the STS-AKI score. Results: An AKI occurred in 26.7% of the patients. The STS-AKI score performed well in this cohort (AUC: 0.736). The MBG levels displayed a decreasing trend in the whole population after surgery ( p = 0.02). However, in the AKI patients, MBG increased at 4 and 8 h before decreasing at 12 h post-surgery. The MBG changes from the baseline to 8 h and from 8 to 12 h post-surgery showed a remarkable diagnostic accuracy for an AKI (AUCs: 0.917 and 0.843, respectively). Integrating these MBG changes with the STS-AKI score significantly improved the model performance, including discrimination, calibration, and risk reclassification. Conclusions : The MBG measurement, particularly any dynamic changes post-surgery, enhances AKI risk stratification in cardiac surgery patients. Integrating MBG with the STS-AKI score offers more accurate risk predictions, potentially leading to better patient management and outcomes.

Background : Biomarkers development for prognostication or prediction of perioperative myocardial disease is critical for the evolution of treatment options in patients undergoing cardiac surgery. The aim of our prospective monocentric study was to investigate the role of selenoprotein 1 (SEEP 1) as a potential biomarker for assessing the risk of myocardial injury after cardiac surgery. Methods : Circulating SEPP1 was measured in the blood of 45 patients before surgery and at 4 h, 8 h and 12 h after CPB by enzyme-linked immunosorbent assay (ELISA); (3) Results : circulating SEPP-1 levels measured 4 h after surgery were strongly correlated with CK-MB levels measured at 48 h (R = 0.598, p < 0.0001) and at 72 h (R = 0.308, p = 0.05). Close correlations were also found between 4 h SEPP-1 and Hs-c troponin values measured at 24 h (R = 0.532, p < 0.0001), 48 h (R = 0.348, p = 0.01) and 72 h (R = 0.377, p = 0.02), as well as with cardiopulmonary bypass (CPB) (R = 0.389, p = 0.008) and cross-clamp time (R = 0.374, p = 0.001); (4) Conclusions : Early SEPP1 measurement after CPB may hold great potential for identifying cardiac surgery patients at risk of developing perioperative myocardial injury.

Background: The transition from in-hospital intravenous administration to subcutaneous therapies to treat inflammatory bowel disease (IBD) can raise some concerns among patients due to the self-administration concerns, the management of potential side effects and the overall worries related to a change of treatment. This study aimed at evaluating patients' opinion about the switch from intravenous to subcutaneous formulations and their knowledge on new available therapeutic options., Methods: We conducted a survey using a questionnaire prepared by a team of gastroenterologists and nurses working at the IBD unit. It consists of 31 items and has been divided into four sections: descriptive, commitment, knowledge and passage mode opinion. The questions were formulated in Italian and conceived according to daily consultations with patients in everyday practice, without any previous piloting or specific medical literature reference. The survey was administered to consecutive IBD patients in intravenous biological treatment; patients currently or previously treated with subcutaneous therapy were excluded., Results: Four hundred questionnaires were distributed to participants. As many as 311 patients (77.7%) completed the survey, while the remaining were excluded from the analysis; 155 (49.8%) patients were favorable to switch from intravenous to subcutaneous therapy, while only 78 (25.1%) disagreed. In univariate and multi-variate analysis, the approval rate for home therapy was significantly associated with the distance from the IBD center and work/family/personal commitments. Surprisingly, only a quarter of the IBD patients knew that almost all available therapeutic agents have a subcutaneous administration route. Regarding patients' opinion on the efficacy of subcutaneous administration of biological agents compared to intravenous drugs, 194 (63%) had no definite idea, while 44 (14%) believed that the effectiveness could be reduced., Conclusion: The transition from in-hospital to subcutaneous therapeutic management of biological therapy at home was generally viewed favorably by patients, especially if they have commitments or were residents far from the IBD center., (© 2024. Indian Society of Gastroenterology.)

Background: In the inflammatory bowel disease (IBD) multidisciplinary team, a key figure is the IBD care manager, usually an independent practice nurse, responsible for evidence-based assessment, care planning, treatment evaluation, and provision of practical information, health education, and emotional support to patients. The objective of this study was to evaluate the profile of this figure in Italy., Methods: A team of experienced nurses created a questionnaire based on the Second N-ECCO declaration, which was administered to nurses who worked in an IBD unit for a period of at least 3 years. A definition of IBD care manager was provided to every participant. The questionnaire consisted of 3 sections: behavioral, knowledge and managerial skills that an IBD care manager should exhibit. Results were studied in relation to the benefits for the patient, organizational advantages, clinical advantages and Italian state of the art., Results: Fifty-five nurses participated in the study, from 28 Italian centers. In the evaluation of behavioral skills of IBD care managers, "management and support of the pregnant patient" was the lowest scored item, while "patient privacy" obtained higher scores. In the evaluation of knowledge, "knowledge of intimacy and sexuality" obtained the lowest scores, while "knowledge of psychophysical and social impact of the disease" obtained a higher score. In managerial skills "management of pain" obtained the lowest scores., Conclusion: Our study confirmed that IBD care managers are invaluable nursing figures within the multidisciplinary team that cares for IBD patients, providing benefits to both patients' clinics and management., Competing Interests: Conflict of Interest: None, (Copyright: © Hellenic Society of Gastroenterology.)

Background and Aims: Subcutaneous vedolizumab formulation has been shown to be as effective and safe as the intravenous one in randomized control trials. Real-life data are limited especially for patients receiving long-term intravenous therapy. This study aimed to evaluate the safety and effectiveness of switching from intravenous to subcutaneous vedolizumab in a large cohort of patients with stable clinical remission., Methods: In this prospective cohort study, we enrolled consecutive patients attending our center between September 2021 and April 2022. The baseline demographic characteristics, 12- and 24-weeks follow-up clinical activity, C-reactive protein levels, and adverse events were recorded. The primary endpoint was to assess combined steroid-free clinical remission plus biochemical remission 24-week after the switch., Results: 93 patients (43 Crohn's disease, 50 ulcerative colitis), switched to subcutaneous vedolizumab after a median duration of intravenous treatment of 36 months [IQR 16-52]. At baseline, 80 patients (86%) had a combined remission. At 24-week, 89.2% (n=74) maintained combined steroid-free clinical remission plus biochemical remission. 25 adverse events were reported, mostly SARS-CoV-2 infections and injection site reactions, with a further four recurrence episodes. Twelve patients (12.9%) discontinued subcutaneous administration and restarted intravenous vedolizumab., Conclusions: Switching from intravenous to subcutaneous vedolizumab can be considered effective and safe for maintaining remission in patients with inflammatory bowel disease. In addition, this might reduce healthcare costs. However, large-scale real-life studies with long-term follow-up are necessary.

The effectiveness of fecal microbiota transplantation (FMT) in ulcerative colitis (UC) remains unclear. This study aimed to investigate the feasibility and effectiveness of serial fecal infusions via colonoscopy in patients with active UC. Subjects with mild-to-moderate UC received three consecutive fecal infusions via colonoscopy. A control population with the same baseline features receiving Infliximab treatment was enrolled. Adverse events and clinical, endoscopic, and microbial outcomes were investigated. Nineteen patients with mildly-to-moderately active UC were enrolled. Clinical response was obtained in six patients at week 2, in eight at week 6, and in nine at week 12. Clinical response was maintained in eight patients at week 24. Endoscopic remission at week 12 was reached in six patients. In the control population, 13/19 patients achieved clinical response at week 6, and 10/19 patients maintained clinical response after 6 months. Microbiota richness was higher in responders compared with the non-responders. Peptostreptococcus , Lactobacillus , and Veillonella were higher in non-responders, while Parabacteroides , Bacteroides , Faecalibacterium , and Akkermansia were higher in responders at all timepoints. Serial FMT infusions appear to be feasible, safe, and effective in UC patients, with a potential role in inducing and maintaining clinical response. Specific bacteria predict the response to FMT.

This study demonstrated the value of using electrical impedance spectroscopy in primary care to manage and diagnose pigmented skin lesions.

Hypertrophic cardiomyopathy (HCM) is a genetic condition determined by an altered collagen turnover of the extracellular matrix. Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) are abnormally released in patients with HCM. The purpose of this systematic review was to thoroughly summarize and discuss the existing knowledge of MMPs profile in patients with HCM. All studies meeting the inclusion criteria (detailed data regarding MMPs in patients with HCM) were selected, after screening the literature from July 1975 to November 2022. Sixteen trials that enrolled a total of 892 participants were included. MMPs-particularly MMP2-levels were found higher in HCM patients compared to healthy subjects. MMPs were used as biomarkers after surgical and percutaneous treatments. Understanding the molecular processes that control the cardiac ECM's collagen turnover allows for a non-invasive evaluation of HCM patients through the monitoring of MMPs and TIMPs.

Background and Aims: Adalimumab (ADA) biosimilars have been included into the therapeutic armamentarium of inflammatory bowel disease (IBD); however, comparative data on the efficacy and safety of the different ADA biosimilars after replacing the ADA originator for a non-medical reason remains scarce. We aimed to compare in a real-life setting the efficacy and safety of four ADA biosimilars SB5, APB501, GP2017, and MSB11022 in IBD patients after replacing the originator for a non-medical reason., Methods: A multicenter retrospective study was performed on consecutive IBD patients, analyzing clinical, laboratory, and endoscopic data. The primary endpoints of the study were maintenance of clinical remission and safety of the different biosimilars., Results: 153 patients were enrolled, 26 with UC and 127 with CD. Clinical remission was maintained in 124 out of 153 (81%) patients after a median (IQR) follow-up of 12 (6-24) months, without any significant difference between the four ADA biosimilars. ADA biosimilars dosage was optimized in five patients (3.3%). Loss of remission was significantly higher in UC patients (10/26 patients, 38.5%) than in CD patients (19/127 patients, 14.9%, p<0.025). Adverse events occurred in 12 (7.9%) patients; the large majority were mild., Conclusions: No difference in efficacy and safety was found between ADA biosimilars when used to replace the ADA originator for a non-medical reason. However, in UC patients the replacement of ADA originator for this reason should be carefully assessed.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has raised concerns in patients with inflammatory bowel disease (IBD), not only due to consequences of coronavirus disease 2019 itself but also as a possible cause of IBD relapse. The main objective of this study was to assess the role of SARS-CoV-2 in IBD clinical recurrence in a cohort of patients undergoing biological therapy. Second, we evaluated the difference in C-reactive protein (CRP) levels between the start and end of the follow-up period (ΔCRP) and the rate of biological therapy discontinuation. Patients with IBD positive for SARS-CoV-2 infection were compared with non-infected patients. IBD recurrence was defined as the need for intensification of current therapy. We enrolled 95 IBD patients with SARS-CoV-2 infection and 190 non-infected patients. During follow-up, 11 of 95 (11.6%) SARS-CoV-2-infected patients experienced disease recurrence compared to 21 of 190 (11.3%) in the control group (p = 0.894). Forty-six (48.4%) SARS-CoV-2-infected patients discontinued biological therapy versus seven (3.7%) in the control group (p < 0.01). In the multivariate analysis, biological agent discontinuation (p = 0.033) and ΔCRP (p = 0.017), but not SARS-CoV-2 infection (p = 0.298), were associated with IBD recurrence. SARS-CoV-2 infection was not associated with increased IBD recurrence rates in this cohort of patients treated with biological agents.

The coronavirus disease 2019 (COVID-19) pandemic is having a major clinical as well as organisational impact on the national health-care system in Italy, particularly in high-volume hospitals which are usually active for many essential clinical needs, including inflammatory bowel disease (IBD). Here, we report major clinical and organisational challenges at a high-volume Italian IBD centre one month after the start of the Italian government's restrictions due to the COVID-19 pandemic. All routine follow-up IBD visits of patients in remission were cancelled or rescheduled for 8-12 weeks' time. However, access to the hospital for therapy or for unstable/relapsing patients was not considered postponable. Everyone attending the centre (e.g. physicians, nurses, administrative personnel and patients) were advised to respect the general recommended rules for hand hygiene and social distancing, to disclose if they had a fever or cough or flu-like symptoms and to wear a surgical mask and gloves. At the entrance of the therapy area, a control station was set up in order to double-check all patients with a clinical interview and conduct thermal scanning. A total of 1451 IBD patients under biotechnological or experimental therapy actively followed in the CEMAD IBD centre were included in the study. About 65% of patients maintained their appointment schedules without major problems, while in 20% of cases planned infusions were delayed because of the patient's decision or practical issues. About 10% of patients receiving subcutaneous therapy were allowed to collect their medicine without a follow-up visit. Finally, 10% of patients living outside the Lazio region requested access to their therapy at a local centre closer to their home. At present, five patients have been found to be positive for SARS-CoV-2 infection but with minimal symptoms, 22 are in 'quarantine' for contact considered to be 'at risk' for the infection. Up to now, none of them has experienced significant symptoms. This study represents the first observational detailed report about short-term impact of the COVID-19 pandemic on patient organisation and management in a high-volume IBD centre.

Antecedentes: Los quistes broncogénicos esofágicos son sacos cerrados originados de brotes anormales del tubo -traqueobronquial primitivo. Estas lesiones suelen ser asintomáticas, por lo que pueden hallarse incidentalmente o pueden causar síntomas por compresión de estructuras adyacentes. Son lesiones muy poco comunes; se han publicado unos 23 casos en adultos., Caso Clínico: Presentamos el caso de un varón de 44 años con un cuadro de tos de larga duración, sin otro síntoma. Para descartar las causas más comunes de sus síntomas se realizan estudios que objetivan la presencia de una lesión intramural de 40 × 43 mm. Se realiza videotoracoscopia para su resección y estudio, resultando ser un quiste broncogénico., Background: Bronchogenic cysts are close sacks originated from abnormal development of the tracheobronchial tree. These lesions are usually asymptomatic or can cause symptoms, by compression of adjacent structures. This pathology is so unusual that there are only about 23 cases published in adults., Case Report: We report a case of a 44 year-old man with persistent cough, without other symptom. The most common causes for his symptoms were ruled out, so imaging studies were made, showing at the medial portion of the esophagus, located intramural a 40 × 43 mm ovoid lesion. Resected by video-assisted thoracoscopy for its study. With findings attributable to bronchogenic cyst., (Copyright: © 2020 Permanyer.)

(1) Background: There is growing interest in the assessment of muscular mass in inflammatory bowel disease (IBD) as sarcopenia is associated with important outcomes. The aim of the study was to evaluate the percentage of sarcopenia in IBD patients, characterizing methods for assessment and clinical symptoms associated to it. (2) Methods: Consecutive IBD patients accessing the Fondazione Policlinico Agostino Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) were enrolled. Healthy patients, elderly or elderly sarcopenic patients, were enrolled as controls. Skeletal muscle mass was evaluated by Dual Energy X-ray Absorptiometry (DEXA) or Bio-Impedensometric Analysis (BIA). Asthenia degree was assessed by subjective visual analogue scales (VAS). Quality of life was measured by the EQ-5D questionnaire. (3) Results: Patients with IBD showed a significant reduction in skeletal muscle mass than healthy controls with lower DEXA and BIA parameters. Moreover, IBD patients presented a lower perception of muscle strength with a higher incidence of asthenia and reduction in quality of life when compared with healthy controls. A significant association between loss in skeletal muscle mass and high asthenia degree was found, configuring a condition of sarcopenia in about one third of patients with IBD. (4) Conclusions: Sarcopenia is common in IBD patients and it is associated with fatigue perception as well as a reduction in quality of life. Therefore, routine assessment of nutritional status and body composition should be a cornerstone in clinical practice, bringing gastroenterologists and nutritionists closer together for a compact, defined picture.

Objective: In late 2006, our hospital implemented use of the QuantiFERON-TB Gold (QFT-G) assay, a whole-blood interferon-gamma release assay, for detection of tuberculosis infection. All newly hired healthcare workers (HCWs) with positive Mantoux tuberculin skin test (TST) results were routinely tested with the QFT-G assay, to take advantage of its higher specificity. We then undertook a quality assurance review to evaluate the QFT-G test results in HCWs with multiple risk factors for latent tuberculosis infection (LTBI)., Methods: The clinical records for TST-positive HCWs tested with the QFT-G assay were reviewed. HCWs with 2 or more risk factors commonly associated with LTBI were classified as "increased risk" (IR). IR HCWs who had negative QFT-G test results underwent repeat QFT-G testing and were offered testing with a different interferon-gamma release assay (T-SPOT.TB) and with extended T cell stimulation assays., Results: Of 143 TST-positive HCWs tested with the QFT-G assay, 26 (18%) had positive results, 115 (81%) had negative results, and 2 (1%) had indeterminate results. Of 82 IR HCWs, 23 (28%) had positive QFT-G test results, and 57 (70%) had negative results. Of the 57 IR HCWs with negative results, 43 underwent repeat QFT-G testing: 41 had negative results again, and 2 had positive results. These 43 HCWs were also offered additional testing with the T-SPOT.TB diagnostic, and 36 consented: 31/36 tested negative, and 5/36 tested positive. Extended assays using the antigens ESAT-6 and CFP-10 confirmed the positive results detected by the overnight assays and yielded positive results for an additional 7/36 (19%) of individuals; strikingly, all 36 HCWs had strongly positive test results with assays using purified protein derivative., Conclusions: The extreme discordance between the results of our clinical diagnostic algorithm and the results of QFT-G testing raises concern about the sensitivity of the QFT-G assay for detection of LTBI in our HCWs. Results of extended stimulation assays suggest that many of our IR HCWs have indeed been sensitized to Mycobacterium tuberculosis. It is possible that the QFT-G assay identifies those at higher reactivation risk rather than all previously infected, but, in the absence of long-term follow-up data, we should interpret negative QFT-G results with some caution.

Genetic differences in body fat, body weight, follicle number, and egg production were found among six inbred lines of White Leghorn hens derived from a common outbred base population. High positive genetic correlations of body fat with body weight were found between inbred lines as well as between inbred parents and line-cross progeny. Heterosis of fatness, body weight, egg production, egg weight, and liver weight were observed. Large follicles and liver weight were unaffected by inbreeding and crossing of lines.

This study was designed to estimate heterosis and recombination loss of feed efficiency at peak egg production using six inbred White Leghorn lines and their crosses. Percent hen day egg production was highest in three-line crosses with 94.6%, 93.5% for two-line crosses and 91.0% for inbred lines, respectively. Feed efficiency of three-line crosses was superior to that of two-line crosses, primarily because of low feed consumption. Heterosis effects for body and egg weights were observed in all mating combinations. The value of heterosis for egg number and feed efficiency were dependent upon parental line. Egg number and egg weight showed small average recombination losses, depending on lines involved. Small but consistent recombination loss for body weight was observed. The recombination loss for feed efficiency was large and negative; the highest three-line cross value for this trait was about 16% above that of the mean of the corresponding two-line crosses.