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Background & Aims: As citrulline is produced by small intestine, plasma citrulline concentration is decreased and may become essential in patients with short bowel syndrome (SBS). In a rat model of SBS, citrulline supplementation enhanced muscle protein synthesis. The aim of the study was to determine whether citrulline impacts whole body protein metabolism in patients with SBS., Methods: Nine adults with non-malignant SBS (residual small bowel 90 ± 48 cm; mean ± SD) who were in near-normal nutritional status without any artificial nutrition, were recruited long after surgery. They received 7-day oral supplementation with citrulline (0.18 g/kg/day), or an iso-nitrogenous placebo in a randomized, double-blind, cross-over design with a 13-day wash-out between regimens, and an intravenous 5-h infusion of L-[1- 13 C]-leucine in the postabsorptive state to assess protein metabolism after each regimen., Results: Plasma citrulline concentration rose 17-fold (25 ± 9 vs. 384 ± 95 μmol/L) and plasma arginine 3-fold after oral citrulline supplementation (both p < 4 × 10 -6 ). Supplementation did not alter leucine appearance rate (97 ± 5 vs. 97 ± 5 μmol kg -1 .h -1 ; p = 0.88), leucine oxidation (14 ± 1 vs. 12 ± 1 μmol kg -1 .h -1 ; p = 0.22), or non-oxidative leucine disposal (NOLD), an index of whole-body protein synthesis (83 ± 4 vs. 85 ± 5 μmol kg -1 .h -1 ; p = 0.36), nor insulin or IGF-1 plasma concentrations. In each of the 3 patients with baseline citrulline<20 μmol/L, citrulline supplementation increased NOLD. Among the 7 patients with plasma citrulline <30 μmol/L, the effect of supplementation on NOLD correlated inversely (r 2  = 0.81) with baseline plasma citrulline concentration., Conclusion: 1) Oral citrulline supplementation enhances citrulline and arginine bioavailability in SBS patients. 2) Oral citrulline supplementation does not have any anabolic effect on whole body protein metabolism in patients with SBS in good nutritional status, in the late phase of intestinal adaptation, and with near-normal baseline citrulline homeostasis. 3) Whether oral citrulline would impact whole body protein anabolism in severely malnourished SBS patients in the early adaptive period, and with baseline plasma citrulline below 20 μmol/L, warrants further study. Registered under ClinicalTrials.gov Identifier no. NCT01386034., (Copyright © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Cdc20 and Cdh1 activate the anaphase-promoting complex/cyclosome, a master cell cycle regulator. Although cell cycle modifications occur during differentiation of stem cells, a role for the anaphase-promoting complex/cyclosome on stem cell fate has not been established in embryonic or adult human tissues. We found that differentiated human primary keratinocytes from the skin express extremely low levels of Cdc20 compared with human primary keratinocyte stem cells (holoclones). In agreement with this, staining of human skin biopsies showed that Cdc20 is expressed in occasional cells from the basal and epibasal layers of the epidermis and is absent from the differentiated layers. Conversely, Cdh1 is preferentially expressed in differentiated cells. Interestingly, partial silencing of Cdc20 enhanced differentiation, indicating that loss of Cdc20 might be a cause rather than a consequence of terminal differentiation. By contrast, Cdh1 silencing induced the opposite cellular phenotype, which was characterized by an increase in stemness, cellular proliferation, and loss of differentiation markers. These data pinpoint the anaphase-promoting complex/cyclosome as a key regulator of adult stem cell fate. They also demonstrate the critical and opposing roles of Cdc20 and Cdh1 in controlling the balance between human primary keratinocyte proliferation and differentiation, and therefore in regulating skin homeostasis., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

There is a widespread agreement from patient and professional organisations alike that the safety of stem cell therapeutics is of paramount importance, particularly for ex vivo autologous gene therapy. Yet current technology makes it difficult to thoroughly evaluate the behaviour of genetically corrected stem cells before they are transplanted. To address this, we have developed a strategy that permits transplantation of a clonal population of genetically corrected autologous stem cells that meet stringent selection criteria and the principle of precaution. As a proof of concept, we have stably transduced epidermal stem cells (holoclones) obtained from a patient suffering from recessive dystrophic epidermolysis bullosa. Holoclones were infected with self-inactivating retroviruses bearing a COL7A1 cDNA and cloned before the progeny of individual stem cells were characterised using a number of criteria. Clonal analysis revealed a great deal of heterogeneity among transduced stem cells in their capacity to produce functional type VII collagen (COLVII). Selected transduced stem cells transplanted onto immunodeficient mice regenerated a non-blistering epidermis for months and produced a functional COLVII. Safety was assessed by determining the sites of proviral integration, rearrangements and hit genes and by whole-genome sequencing. The progeny of the selected stem cells also had a diploid karyotype, was not tumorigenic and did not disseminate after long-term transplantation onto immunodeficient mice. In conclusion, a clonal strategy is a powerful and efficient means of by-passing the heterogeneity of a transduced stem cell population. It guarantees a safe and homogenous medicinal product, fulfilling the principle of precaution and the requirements of regulatory affairs. Furthermore, a clonal strategy makes it possible to envision exciting gene-editing technologies like zinc finger nucleases, TALENs and homologous recombination for next-generation gene therapy., (© 2015 The Authors. Published under the terms of the CC BY 4.0 license.)

The skin is privileged because several skin-derived stem cells (epithelial stem cells from epidermis and its appendages, mesenchymal stem cells from dermis and subcutis, melanocyte stem cells) can be efficiently captured for therapeutic use. Main indications remain the permanent coverage of extensive third degree burns and healing of chronic cutaneous wounds, but recent advances in gene therapy technology open the door to the treatment of disabling inherited skin diseases with genetically corrected keratinocyte stem cells. Therapeutic skin stem cells that were initially cultured in research or hospital laboratories must be produced according strict regulatory guidelines, which ensure patients and medical teams that the medicinal cell products are safe, of constant quality and manufactured according to state-of-the art technology. Nonetheless, it does not warrant clinical efficacy and permanent engraftment of autologous stem cells remains variable. There are many challenges ahead to improve efficacy among which to keep telomere-dependent senescence and telomere-independent senescence (clonal conversion) to a minimum in cell culture and to understand the cellular and molecular mechanisms implicated in engraftment. Finally, medicinal stem cells are expansive to produce and reimbursement of costs by health insurances is a major concern in many countries., (© 2012 Elsevier Ltd. All rights reserved.)

Objective: To determine whether specific steps taken after a critical quality control of our results in hypospadias surgery lead to a decrease in fistula rate., Patients and Methods: Retrospective review of prospectively collected data. Between 1994 and 2001, our series of 85 tubularized plate urethroplasties (modified Duplay or Duplay-Snodgrass procedure) had a fistula rate of 25.9%. In 2001, we modified our approach by systematically padding the urethral suture with a layer of vascularized subcutaneous preputial tissue, as described by Snodgrass. Scrotal hypospadias were excluded. Surgical outcome was assessed at 1 and 12 months. In both groups, all repairs were performed by or under direct supervision of the senior author (BJM)., Results: After 2001, 57 hypospadias repairs were performed in 57 patients aged 8 months to 14 years (median 1.4 years). Fistula occurred in two cases, one of which closed spontaneously within 6 months. Our fistula rate had dropped to 3.5%, with a minimum follow up of 12 months., Conclusion: Covering the urethral suture with a padding flap of vascularized preputial tissue helps avoid fistula formation. Technique modification after critical appraisal of our own series led to a much better outcome in this demanding surgery.

The relationship between cataract prevalence, altitude, and sunlight hours was investigated in a large national probability sample survey of 105 sites in the Himalayan kingdom of Nepal, December 1980 through April 1981. Cataract of senile or unknown etiology was diagnosed by ophthalmologists in 873 of 30,565 full-time life-long residents of survey sites. Simultaneously, the altitude of sites was measured using a standard mountain altimeter. Seasonally adjusted average daily duration of sunlight exposure for each site was calculated by a method which took into account latitude and obstructions along the skyline. Age- and sex-standardized cataract prevalence was 2.7 times higher in sites at an altitude of 185 meters or less than in sites over 1000 meters. Cataract prevalence was negatively correlated with altitude (r = -0.533, p less than 0.0001). However, a positive correlation between cataract prevalence and sunlight was observed (r = 0.563, p less than 0.0001). Sites with an average of 12 hours of sunlight exposure had 3.8 times as much cataract as sites with an average of only seven hours of exposure. Sunlight was blocked from reaching certain high altitude sites by tall neighboring mountains.

Children with different levels of nutritional status were studied to determine their immune response to, and complications from, immunization with live measles vaccine and lyophilized smallpox vaccine. Two hundred forty-one children between the ages of 5 months and 9 years were examined to assess their nutritional status at the time of immunization. Sero-conversion was defined as a hemagglutination-inhibition titer to measles virus, of greater than or equal to 1:20 6 to 8 weeks after vaccination in initially sero-negative children. Of 111 initially sero-negative children 94% had an adequate immune response, shown by sero-conversion. Of 193 children without a smallpox vaccinationscar 97% were successfully immunized against smallpox. These rates of immune response were independent of age, sex, and nutritional status of the children. The geometric mean titer rise to measles immunization of groups, whose nutritional status was normal (greater than 90% of median weight for age), mildly (75 to 90%), moderately (60 to 75%), or severely (less than 60%) malnourished were 7.5, 8.8, 7.9, and 7.9, respectively. Malnutrition did not affect the children's ability to develop adequate immune response to measles of smallpox vaccine, and there were no major complications during the 8-week period of follow-up. Since measles is a very severe disease, which in malnourished children can carry a case fatality rate as high as 50%, malnutrition should be a prime indication for measles immunization, and certainly not a contraindication.

This report presents the major findings of the Nepal Blindness Survey, the first nationwide epidemiological survey of blindness, which was conducted in 1979-80. The survey was designed to gather data that could be used to estimate the prevalence and causes of blindness in the country. Ancillary studies were conducted to obtain information on socioeconomic correlates and other risk factors of blinding conditions and patterns of health care utilization.The nationwide blindness prevalence rate is 0.84%. Cataract is the leading cause of blindness, accounting for over 80% of all avoidable blindness. Trachoma is the most prevalent blinding condition, affecting 6.5% of the population. Very few cases of childhood blindness were detected.The implications of the survey findings for programme planning, health manpower development, and health education are discussed.