Ileocecal vascularized lymph node transfer for the treatment of extremity lymphedema: A case report.

Vascularized lymph node (VLN) transfer has been of high interest in the past decade for the treatment of lymphedema, since it has been shown to be effective in reducing limb volumes, decreasing infectious episodes and improving quality of life. Multiple donor sites have been described in the quest for the optimal one. Herein, we describe a novel lymph node flap option based on the ileocolic artery and vein. The ileocecal vascularized lymph node (IC-VLN) flap was used in the management of a 33-year-old male patient with lower extremity lymphedema secondary to left inguinal trauma. The patient had previously underwent a pedicled omentum flap transposition with minimal improvement in limb size and persistent episodes of infection. At 15 month follow-up, the IC-VLN flap improved the lymphatic drainage in the affected limb with a mean limb circumference reduction rate of 26.3%. No donor site complications or further episodes of infection were noted. According to our findings, the IC-VLN flap may be another option for VLN transfer in very selected cases. Nevertheless, larger series with a longer follow-up are required to analyze the efficacy and long-term results of this flap.

Leishmania donovani development in Phlebotomus argentipes: comparison of promastigote- and amastigote-initiated infections.

Leishmania parasites alternate in their life cycle between promastigote stages that develop in the gut of phlebotomine sand flies and amastigotes residing inside phagocytic cells of vertebrate hosts. For experimental infections of sand flies, promastigotes are frequently used as this way of infection is technically easier although ingestion of promastigotes by sand flies is unnatural. Here we aimed to answer a critical question, to what extent do promastigote-initiated experimental infections differ from those initiated with intracellular amastigotes. We performed side-by-side comparison of Leishmania development in Phlebotomus argentipes females infected alternatively with promastigotes from log-phase cultures or amastigotes grown ex vivo in macrophages. Early stage infections showed substantial differences in parasite load and representation of morphological forms. The differences disappeared along the maturation of infections; both groups developed heavy late-stage infections with colonization of the stomodeal valve, uniform representation of infective metacyclics and equal efficiency of transmission. The results showed that studies focusing on early phase of Leishmania development in sand flies should be initiated with intracellular amastigotes. However, the use of promastigote stages for sand fly infections does not alter significantly the final outcome of Leishmania donovani development in P. argentipes and their transmissibility to the vertebrate host.

Hosts and vectors of Trypanosoma cruzi discrete typing units in the Chagas disease endemic region of the Paraguayan Chaco.

Active Trypanosoma cruzi transmission persists in the Gran Chaco region, which is considered hyperendemic for Chagas disease. Understanding domestic and sylvatic transmission cycles and therefore the relationship between vectors and mammalian hosts is crucial to designing and implementing improved effective control strategies. Here we describe the species of triatomine vectors and the sylvatic mammal reservoirs of T. cruzi, in different localities of the Paraguayan and Bolivian Chaco. We identify the T. cruzi genotypes discrete typing units (DTUs) and provide a map of their geographical distribution. A total of 1044 triatomines and 138 sylvatic mammals were captured. Five per cent of the triatomines were microscopically positive for T. cruzi (55 Triatoma infestans from Paraguay and one sylvatic Triatoma guasayana from Bolivia) and 17 animals (12·3%) comprising eight of 28 (28·5%) Dasypus novemcinctus, four of 27 (14·8%) Euphractus sexcinctus, three of 64 (4·7%) Chaetophractus spp. and two of 14 (14·3%) Didelphis albiventris. The most common DTU infecting domestic triatomine bugs was TcV (64%), followed by TcVI (28%), TcII (6·5%) and TcIII (1·5%). TcIII was overwhelmingly associated with armadillo species. We confirm the primary role of T. infestans in domestic transmission, armadillo species as the principal sylvatic hosts of TcIII, and consider the potential risk of TcIII as an agent of Chagas disease in the Chaco.

The laparoscopic right gastroepiploic lymph node flap transfer for upper and lower limb lymphedema: Technique and outcomes.

BACKGROUND: Lymph node flap transfer popularity for treatment of extremity lymphedema is increasing quickly. Multiple flap donor sites were described in search of the optimal one. We describe the technique and outcomes of a laparoscopically harvested right gastroepiploic lymph node flap for treatment of extremity lymphedema. METHODS: From January 2012 to January 2013, 10 consecutive female patients, average age 54.8 years, with International Society of Lymphology stage II-III extremity lymphedema refractory to conservative management were included. Five patients had upper limb breast cancer-related lymphedema and five patients had lower limb pelvic cancer-related lymphedema. All patients underwent laparoscopic harvest of the right gastroepiploic lymph node flap, transferred to the wrist and ankle as recipient sites. Flaps were covered with a small skin graft taken from the thigh. Perioperative assessment included physical exam, photography, circumference measurements, CT scans, lymphoscintigraphy, and Lymphedema Quality of Life (LYMQOL) questionnaire. Clinical and CT evaluation of donor-site morbidity were performed. RESULTS: The flap survival rate was 100%, with a mean harvest time of 32 minutes and total operating time of 164 minutes. One case required regrafting for skin graft loss. The mean limb reduction rate was 39.5% at a mean follow-up of 14.7 months. Perioperative lymphoscintigraphy demonstrated transferred lymph node viability and lymphatic transport improvement. LYMQOL showed a 2.6-fold quality-of-life improvement (P < 0.01). No donor-site morbidity was encountered. CONCLUSIONS: The use of the laparoscopically harvested right gastroepiploic lymph node flap may be a safe technique that improves limb measurements and quality of life in extremity lymphedema patients. © 2015 Wiley Periodicals, Inc. Microsurgery 37:197-205, 2017.

Free lymph node flap transfer and laser-assisted liposuction: a combined technique for the treatment of moderate upper limb lymphedema.

Upper limb lymphedema following breast cancer surgery is a challenging problem for the surgeon. Lymphatico-venous or lymphatico-lymphatic anastomoses have been used to restore the continuity of the lymphatic system, offering a degree of improvement. Long-term review indicates that lumen obliteration and occlusion at the anastomosis level commonly occurs with time as a result of elevated venous pressure. Lymph node flap transfer is another microsurgical procedure designed to restore lymphatic system physiology but does not provide a complete volume reduction, particularly in the presence of hypertrophied adipose tissue and fibrosis, common in moderate and advanced lymphedema. Laser-assisted liposuction has been shown to effectively reduce fat and fibrotic tissues. We present preliminary results of our practice using a combination of lymph node flap transfer and laser-assisted liposuction. Between October 2012 and May 2013, ten patients (mean 54.6 ± 9.3 years) with moderate (stage II) upper extremity lymphedema underwent groin or supraclavicular lymph node flap transfer combined with laser-assisted liposuction (high-power diode pulsed laser with 1470-nm wavelength, LASEmaR 1500-EUFOTON, Trieste, Italy). A significant decrease of upper limb circumference measurements at all levels was noted postoperatively. Skin tonicity was improved in all patients. Postoperative lymphoscintigraphy revealed reduced lymph stasis. No patient suffered from donor site morbidity. Our results suggest that combining laser liposuction with lymph node flap transfer is a safe and reliable procedure, achieving a reduction of upper limb volume in treated patients suffering from moderate upper extremity lymphedema.

Reconstruction after orbital exenteration using gracilis muscle free flap.

BACKGROUND: Orbital exenteration (OE) is a disfiguring procedure, which typically includes the removal of the entire eyeball including the globe, extraocular muscles, and periorbital soft tissues after malignancies excision or trauma. Several methods of orbital reconstruction have been attempted with varying success. In this report, we analyze results of the use of gracilis muscle free flap for reconstruction of OE defects and its feasibility for prosthetic rehabilitation. METHODS: Nine consecutive patients treated at the China Medical University Hospital of Taichung during January 2009 to January 2013, who had gracilis free flap reconstruction after OEs, were retrospectively reviewed. Cancer in six patients and trauma in remaining three patients was the cause for OE. RESULTS: Nine patients who underwent reconstruction with gracilis free tissue transfer had a successful outcome. There was not any donor or recipient site morbidity; however, one patient was deceased during follow-up period due to metastasis. The mean follow-up period was 23.5 months. Cosmetic results were acceptable both to patients and to surgeons. CONCLUSIONS: Gracilis free flap to repair OE defects may be a safe alternative for reconstruction. It provides a larger volume of well-vascularized tissue, greater placement flexibility, and minor donor site morbidity without any significant functional deficit.

Comparative genomics of Leishmania donovani progeny from genetic crosses in two sand fly species and impact on the diversity of diagnostic and vaccine candidates.

Sand fly transmitted Leishmania species are responsible for severe, wide ranging, visceral and cutaneous leishmaniases. Genetic exchange can occur among natural Leishmania populations and hybrids can now be produced experimentally, with limitations. Feeding Phlebotomus orientalis or Phlebotomus argentipes on two strains of Leishmania donovani yielded hybrid progeny, selected using double drug resistance and fluorescence markers. Fluorescence activated cell sorting of cultured clones derived from these hybrids indicated diploid progeny. Multilocus sequence typing of the clones showed hybridisation and nuclear heterozygosity, although with inheritance of single haplotypes in a kinetoplastid target. Comparative genomics showed diversity of clonal progeny between single chromosomes, and extraordinary heterozygosity across all 36 chromosomes. Diversity between progeny was seen for the HASPB antigen, which has been noted previously as having implications for design of a therapeutic vaccine. Genomic diversity seen among Leishmania strains and hybrid progeny is of great importance in understanding the epidemiology and control of leishmaniasis. As an outcome of this study we strongly recommend that wider biological archives of different Leishmania species from endemic regions should be established and made available for comparative genomics. However, in parallel, performance of genetic crosses and genomic comparisons should give fundamental insight into the specificity, diversity and limitations of candidate diagnostics, vaccines and drugs, for targeted control of leishmaniasis.

Infraorbital nerve schwannoma presenting as an upper lip mass in an adolescent boy.

BACKGROUND: Schwannomas of the head and neck are uncommon tumors that arise from the nerve sheath and may afflict peripheral, autonomic, or cranial nerves. It is important to consider the possible differential diagnoses of a nasolabial lump in a child because its appropriate treatment varies widely. METHODS: The authors describe a case of a 12-year-old boy who presented with a 2.5-cm right nasolabial subcutaneous lump of 3 months in duration. Computed tomographic scan showed a homogeneously attenuated lesion. RESULTS: An intraoral incision was used for complete extirpation of this tumor while preserving the infraorbital nerve and facial aesthetics in this adolescent boy. Histopathologic examination showed palisades of spindle cells and Verocay bodies characteristic of schwannomas. The patient has been followed up for 2 years with no clinical evidence of recurrence. CONCLUSIONS: Only 9 cases of infraorbital nerve schwannoma have been described in literature, and the sublabial intraoral incision was attempted in only 1 case. The authors describe a rare case of an extraosseous schwannoma arising from the infraorbital nerve that presented as a cheek lump, its workup, its differentials, its treatment, and a review of literature. The use of a preoperative computed tomographic scan permitted the use of a sublabial intraoral incision with good visual access to the lesion and facilitated its complete extirpation without incurring external scars.

Supraorbital nerve conduction study in normal subjects.

There is currently no examination technique that allows direct measurement of supraorbital nerve conduction velocity and amplitude. Therefore, in this study we describe a novel nerve conduction technique that allows measurement of the supraorbital sensory nerve action potential (SNAP) distal to the supraorbital foramen. Supraorbital SNAPs were recorded bilaterally from 17 healthy volunteers using an antidromic technique. The SNAPs were consistently recordable over the site 6 cm lateral to the midline point that was marked 10 cm above the nasion. Measured parameters included peak latency (mean 2.3 ms, SD 0.3), amplitude (mean 14.6 µV; SD 10.5), and velocity (mean 51.3 m/s, SD 6.8). The mean percentage of interside difference in amplitude was 25.6% (SD 17.3). Cut-off values (97th percentile) were 2.7 ms (peak latency), 3.3 µV (amplitude), 41.9 m/s (conduction velocity), and 54.9% (interside difference in amplitude). Supraorbital SNAPs can be recorded in all normal subjects and used as a quantitative measure of the functioning large fibers in the nerve.

Microevolution of Trypanosoma cruzi reveals hybridization and clonal mechanisms driving rapid genome diversification.

Protozoa and fungi are known to have extraordinarily diverse mechanisms of genetic exchange. However, the presence and epidemiological relevance of genetic exchange in Trypanosoma cruzi, the agent of Chagas disease, has been controversial and debated for many years. Field studies have identified both predominantly clonal and sexually recombining natural populations. Two of six natural T. cruzi lineages (TcV and TcVI) show hybrid mosaicism, using analysis of single-gene locus markers. The formation of hybrid strains in vitro has been achieved and this provides a framework to study the mechanisms and adaptive significance of genetic exchange. Using whole genome sequencing of a set of experimental hybrids strains, we have confirmed that hybrid formation initially results in tetraploid parasites. The hybrid progeny showed novel mutations that were not attributable to either (diploid) parent showing an increase in amino acid changes. In long-term culture, up to 800 generations, there was a variable but gradual erosion of progeny genomes towards triploidy, yet retention of elevated copy number was observed at several core housekeeping loci. Our findings indicate hybrid formation by fusion of diploid T. cruzi, followed by sporadic genome erosion, but with substantial potential for adaptive evolution, as has been described as a genetic feature of other organisms, such as some fungi.

Application of an adapted FMEA framework for robot-inclusivity of built environments.

Mobile robots are deployed in the built environment at increasing rates. However, lack of considerations for a robot-inclusive planning has led to physical spaces that would potentially pose hazards to robots, and contribute to an overall productivity decline for mobile service robots. This research proposes the use of an adapted Failure Mode and Effects Analysis (FMEA) as a structured tool to evaluate a building's level of robot-inclusivity and safety for service robot deployments. This Robot-Inclusive FMEA (RIFMEA) framework, is used to identify failures in the built environment that compromise the workflow of service robots, assess their effects and causes, and provide recommended actions to alleviate these problems. The method was supported with a case study of deploying telepresence robots in a university campus. The study concluded that common failures were related to poor furniture design, a lack of clearance and hazard indicators, and sub-optimal interior planning.

Genome-scale multilocus microsatellite typing of Trypanosoma cruzi discrete typing unit I reveals phylogeographic structure and specific genotypes linked to human infection.

Trypanosoma cruzi is the most important parasitic infection in Latin America and is also genetically highly diverse, with at least six discrete typing units (DTUs) reported: Tc I, IIa, IIb, IIc, IId, and IIe. However, the current six-genotype classification is likely to be a poor reflection of the total genetic diversity present in this undeniably ancient parasite. To determine whether epidemiologically important information is "hidden" at the sub-DTU level, we developed a 48-marker panel of polymorphic microsatellite loci to investigate population structure among 135 samples from across the geographic distribution of TcI. This DTU is the major cause of resurgent human disease in northern South America but also occurs in silvatic triatomine vectors and mammalian reservoir hosts throughout the continent. Based on a total dataset of 12,329 alleles, we demonstrate that silvatic TcI populations are extraordinarily genetically diverse, show spatial structuring on a continental scale, and have undergone recent biogeographic expansion into the southern United States of America. Conversely, the majority of human strains sampled are restricted to two distinct groups characterised by a considerable reduction in genetic diversity with respect to isolates from silvatic sources. In Venezuela, most human isolates showed little identity with known local silvatic strains, despite frequent invasion of the domestic setting by infected adult vectors. Multilocus linkage indices indicate predominantly clonal parasite propagation among all populations. However, excess homozygosity among silvatic strains and raised heterozygosity among domestic populations suggest that some level of genetic recombination cannot be ruled out. The epidemiological significance of these findings is discussed.

Cancer of the gastric cardia is rising in incidence in an Asian population and is associated with adverse outcome.

BACKGROUND: Tumors arising from the esophagogastric junction (OGJ) are increasing in incidence in the west, but data from Asian populations are conflicting. Singapore has a mixed-Asian population with an international lifestyle. This study was designed to examine the changing trends in incidence of gastric cardia cancer (type III) within this population and to compare the clinicopathological characteristics and outcome of these tumors with gastric tumors. METHODS: Trends in cancer incidence were obtained from the Singapore Cancer Registry. Clinicopathological data were prospectively collected from patients undergoing surgery for gastric cancer who presented to the National University Hospital between 2000 and 2005. Patients underwent surgery with or without (neo)adjuvant therapy. Survival duration was analyzed. RESULTS: The incidence of cardia tumors has increased each decade since 1968 (1968-1982, 6.3%; 1983-1992, 7.6%; 1993-1997, 8.4%; 1998-2002, 9.1%; 2003-2007, 16.2%). Among the study population (n = 159) cardia tumors were associated with male sex (p < 0.01) and dysphagia (p < 0.01). Although R0 resection rates were similar, systemic recurrence rates were higher among patients with cardia cancer (p = 0.031) and survival was reduced compared with patients with non-cardia gastric cancer (median survival 26 vs. 69 months; p < 0.001). Cardia location of the tumor and metastatic lymph node ratio were identified as independent adverse prognostic indicators on multivariate analysis. CONCLUSIONS: Similar to western societies, the incidence of proximal gastric cancer is increasing in Singapore. Cardia tumors are associated with poorer outcomes, suggesting that cardia cancer is a distinct disease from true gastric cancer requiring different management strategies to improve the outcome for these patients.

The kidney dish as a template for titanium mesh contouring in supraorbital rim fractures: a simple and effective method.

The supraorbital rims are an integral part of facial esthetics and fractures to this region can result in obvious cosmetic deformities. When there is significant bone loss, using titanium mesh is an effective method of reconstructing the supraorbital rim. Conventional methods of contouring the rim include polyurethane skull models, customized implants, and free-form intraoperative bending of the mesh. Conventional skull models are usually based on an average 6-foot-tall Caucasian man and may not accurately simulate the supraorbital rim in persons of Asian descent. Free-form bending is associated with mesh contour irregularities, leading to palpability and protrusion and to nonanatomic conformation of mesh. The kidney dish, a commonly available implement in the operating room, can be used as a template for reconstruction of the supraorbital rims and this technique is described in the present report.

Repeat-Driven Generation of Antigenic Diversity in a Major Human Pathogen, Trypanosoma cruzi.

Trypanosoma cruzi, a zoonotic kinetoplastid protozoan parasite, is the causative agent of American trypanosomiasis (Chagas disease). Having a very plastic, repetitive and complex genome, the parasite displays a highly diverse repertoire of surface molecules, with pivotal roles in cell invasion, immune evasion and pathogenesis. Before 2016, the complexity of the genomic regions containing these genes impaired the assembly of a genome at chromosomal level, making it impossible to study the structure and function of the several thousand repetitive genes encoding the surface molecules of the parasite. We here describe the genome assembly of the Sylvio X10/1 genome sequence, which since 2016 has been used as a reference genome sequence for T. cruzi clade I (TcI), produced using high coverage PacBio single-molecule sequencing. It was used to analyze deep Illumina sequence data from 34 T. cruzi TcI isolates and clones from different geographic locations, sample sources and clinical outcomes. Resolution of the surface molecule gene distribution showed the unusual duality in the organization of the parasite genome, a synteny of the core genomic region with related protozoa flanked by unique and highly plastic multigene family clusters encoding surface antigens. The presence of abundant interspersed retrotransposons in these multigene family clusters suggests that these elements are involved in a recombination mechanism for the generation of antigenic variation and evasion of the host immune response on these TcI strains. The comparative genomic analysis of the cohort of TcI strains revealed multiple cases of such recombination events involving surface molecule genes and has provided new insights into T. cruzi population structure.

Genomic analysis of natural intra-specific hybrids among Ethiopian isolates of Leishmania donovani.

Parasites of the genus Leishmania (Kinetoplastida: Trypanosomatidae) cause widespread and devastating human diseases. Visceral leishmaniasis due to Leishmania donovani is endemic in Ethiopia where it has also been responsible for major epidemics. The presence of hybrid genotypes has been widely reported in surveys of natural populations, genetic variation reported in a number of Leishmania species, and the extant capacity for genetic exchange demonstrated in laboratory experiments. However, patterns of recombination and the evolutionary history of admixture that produced these hybrid populations remain unclear. Here, we use whole-genome sequence data to investigate Ethiopian L. donovani isolates previously characterized as hybrids by microsatellite and multi-locus sequencing. To date there is only one previous study on a natural population of Leishmania hybrids based on whole-genome sequences. We propose that these hybrids originate from recombination between two different lineages of Ethiopian L. donovani occurring in the same region. Patterns of inheritance are more complex than previously reported with multiple, apparently independent, origins from similar parents that include backcrossing with parental types. Analysis indicates that hybrids are representative of at least three different histories. Furthermore, isolates were highly polysomic at the level of chromosomes with differences between parasites recovered from a recrudescent infection from a previously treated individual. The results demonstrate that recombination is a significant feature of natural populations and contributes to the growing body of data that shows how recombination, and gene flow, shape natural populations of Leishmania.

Global genome diversity of the Leishmania donovani complex.

Protozoan parasites of the Leishmania donovani complex - L. donovani and L. infantum - cause the fatal disease visceral leishmaniasis. We present the first comprehensive genome-wide global study, with 151 cultured field isolates representing most of the geographical distribution. L. donovani isolates separated into five groups that largely coincide with geographical origin but vary greatly in diversity. In contrast, the majority of L. infantum samples fell into one globally-distributed group with little diversity. This picture is complicated by several hybrid lineages. Identified genetic groups vary in heterozygosity and levels of linkage, suggesting different recombination histories. We characterise chromosome-specific patterns of aneuploidy and identified extensive structural variation, including known and suspected drug resistance loci. This study reveals greater genetic diversity than suggested by geographically-focused studies, provides a resource of genomic variation for future work and sets the scene for a new understanding of the evolution and genetics of the Leishmania donovani complex.