Precontoured dynamic compression plate using patient-specific 3D-printed models in minimally invasive surgical technique for midshaft clavicle fractures.

INTRODUCTION: This study introduced a novel approach for the treatment of midshaft clavicle fractures, utilizing patient-specific 3D-printed models for accurate preoperative contouring of dynamic compression plates (DCPs) and an alternative minimally invasive plate osteosynthesis (MIPO) technique with precontoured DCPs through small vertical separated incisions. PATIENT AND METHODS: Mirror image 3D clavicular models were reproduced from 40 patients with acute displaced midshaft clavicle fractures who underwent MIPO using precontoured DCPs inserted through small, vertical separated incisions. Exclusion criteria included patients with open fractures, pathological fractures, ipsilateral limb injury, skeletal immature patients, and those who had previous clavicle fractures or surgery. Postoperative evaluation was conducted using clinical and radiographic review. The Constant-Murley and American Shoulder and Elbow Surgeons Shoulder Scores were used for clinical evaluations, and the Patient and Observer Scar Assessment Scale was used to assess surgical scars. RESULTS: The average time to union of all fractures was 12.88 weeks (range, 8-15) without loss of reduction. The patient-specific precontoured DCPs fitted well in all cases, with fracture consolidation and minimal three cortical sides connecting the fracture fragment. No hardware prominence and skin complications occurred, and clinical evaluation showed no existing difference compared with the contralateral sides. The average Constant-Murley and American Shoulder and Elbow Surgeons Shoulder Scores were 96.33 ± 3.66 and 93.26 ± 5.15, respectively. Two patients requested their implant removal, and scar qualities were satisfactory. CONCLUSIONS: Our study demonstrated that the use of a patient-specific precontoured DCP, in combination with 3D printing technology, provides accurate preoperative planning, effective fracture reduction, and improved postoperative outcomes in displaced midshaft clavicle fractures. The MIPO with a patient-specific precontoured DCP through separated vertical incisions along the Langer's lines appears to be a promising option, regarding appearance, avoiding associated complications, and obviating the need for reoperation. These results suggest that this technique has merit and can be a viable option for the treatment of midshaft clavicle fractures.

Safe zone of supraclavicular nerve during clavicle fixation and its anatomical variations, a cadaveric study.

BACKGROUND: Supraclavicular nerve injury is usually at risk during clavicular fracture fixation. This study aimed to examine the anatomical features and estimate the precise location of supraclavicular nerve branches related to adjacent structural landmarks and to evaluate the differences between sex and side. To highlight the clinical purposes and surgical relevance, this study attempted to define a surgical safe zone that would probably protect the supraclavicular nerve during clavicle fixation. METHOD: A total of 64 shoulders obtained from 15 female and 17 male adult cadavers were examined, identifying the branching patterns of the supraclavicular nerve, measuring the clavicle length and the course of the supraclavicular nerve referring to the sternoclavicular (SC) and acromioclavicular (AC) joint. Data were categorized by sex and side, and their differences were evaluated using Student T-Test and Mann-Whitney U Test. Clinically relevant predictable safe zones were also statistically analyzed. RESULT: The results revealed 7 branching patterns of the supraclavicular nerve. The medial and lateral nerve branches formed a shared trunk, and the medial nerve branches separated to form the intermediate branch, i.e., the most frequent pattern (67.19%). The safe zones were determined to be 6.1 mm among both sexes of the SC joint medially, and 0.7 mm among females and 0 mm among males of the AC joint laterally. Surgical incisions between 29.3 to 51.2% and 60.5 to 79.7% of the clavicle length from the SC joint were the safe zones at the midclavicular shaft among both sexes. CONCLUSION: The findings of this study have provided new insights into the anatomy of the supraclavicular nerve and its variations. It has been revealed that the terminal branches of the nerve consistently pass over the clavicle in a predictable pattern, emphasizing the importance of considering the supraclavicular nerve's safe zones during clinically relevant surgeries. Nevertheless, due to individual anatomical variations, meticulous dissection between these safe zones is necessary to avoid iatrogenic nerve injury among patients. LEVEL OF EVIDENCE: Basic Science Study, Anatomic Study.

Minimally invasive plate osteosynthesis for displaced midshaft clavicle fractures: An indirect reduction using joystick technique.

BACKGROUND: A minimally invasive plate osteosynthesis (MIPO) technique has become increasingly popular in long bone fracture fixation as it could eliminate postoperative complications. However, the most challenging aspect of employing the MIPO for midshaft clavicle fractures among general orthopedic surgeons is the technically demanding that indirect reduction is typically a closed maneuver. METHODS: We present a consecutive series of patients with displaced midshaft clavicle fractures undergoing clavicular fixation using the MIPO technique between January 2017 and October 2019. The joystick technique was used to obtain anatomical reduction. Clinical outcomes were assessed using the Constant-Murley and the American shoulder and elbow surgeons shoulder scores. RESULTS: Thirty patients with a mean age of 42.44 years were included. The functional shoulder scores showed no disabilities compared with those of a healthy population. No major complications requiring re-operation were noted, and all fractures were completely healed with an average time of 12.53 weeks. CONCLUSION: This study demonstrated that facilitating the MIPO for midshaft clavicle fractures using simple operative devices and techniques was possible. The joystick technique with the use of an external fixator for temporary stabilization is a safe and effective method that can be added to achieve anatomical alignment with the fracture site unexposed. This technique could be performed either in a fresh fracture or a delayed case with failed conservative treatment.

Rhoptry neck protein 11 has crucial roles during malaria parasite sporozoite invasion of salivary glands and hepatocytes.

The malaria parasite sporozoite sequentially invades mosquito salivary glands and mammalian hepatocytes; and is the Plasmodium lifecycle infective form mediating parasite transmission by the mosquito vector. The identification of several sporozoite-specific secretory proteins involved in invasion has revealed that sporozoite motility and specific recognition of target cells are crucial for transmission. It has also been demonstrated that some components of the invasion machinery are conserved between erythrocytic asexual and transmission stage parasites. The application of a sporozoite stage-specific gene knockdown system in the rodent malaria parasite, Plasmodium berghei, enables us to investigate the roles of such proteins previously intractable to study due to their essentiality for asexual intraerythrocytic stage development, the stage at which transgenic parasites are derived. Here, we focused on the rhoptry neck protein 11 (RON11) that contains multiple transmembrane domains and putative calcium-binding EF-hand domains. PbRON11 is localised to rhoptry organelles in both merozoites and sporozoites. To repress PbRON11 expression exclusively in sporozoites, we produced transgenic parasites using a promoter-swapping strategy. PbRON11-repressed sporozoites showed significant reduction in attachment and motility in vitro, and consequently failed to efficiently invade salivary glands. PbRON11 was also determined to be essential for sporozoite infection of the liver, the first step during transmission to the vertebrate host. RON11 is demonstrated to be crucial for sporozoite invasion of both target host cells - mosquito salivary glands and mammalian hepatocytes - via involvement in sporozoite motility.

Protection against Fasciola gigantica infection in mice by vaccination with recombinant juvenile-specific cathepsin L.

Fasciola gigantica cathepsin L1H (FgCatL1H) is one of the major cathepsin L released by juveniles of F. gigantica to aid in the invasion of host's tissues. Due to its high sequence similarity with other cathepsin L (CatL) isoforms of late stage F. gigantica, it was considered to be a good vaccine candidate that can block all CatL-mediated protease activities and affect juveniles as well as adult parasites. In this study, recombinant proFgCatL1H protein expressed in yeast, Pichia pastoris, system was mixed with Freund's adjuvants and used to subcutaneously immunize mice that were later challenged with metacercariae of F. gigantica. The percentage of worm protection in the rproFgCatL1H-vaccinated mice compared to the non-immunized and adjuvant control mice were approximately 62.7% and 66.1%, respectively. Anti-rproFgCatL1H antisera collected from vaccinated mice reacted specifically with rproFgCatL1H and other cathepsin L isoforms of F. gigantica, but the antibodies did not cross react with antigens from other trematode and nematode parasites, including Eurytrema pancreaticum, Opisthorchis viverrini, Fischoederius cobboldi, Cotylophoron cotylophorum, Gigantocotyle explanatum, Paramphistomum cervi, and Setaria labiato-papillosa. The levels of IgG1 and IgG2a in mouse sera increased significantly at two weeks after immunization and were highest during the sixth to eighth weeks after immunization. The IgG1 level was higher than IgG2a at all periods of immunization, implicating the dominance of the Th2 response. The levels of IgG1 and IgG2a in the immune sera were shown to be strongly correlated with the numbers of worm recovery, and the correlation coefficient was higher for IgG1. The levels of serum aspartate aminotransferase and alanine transaminase were significantly lower in the sera of rproFgCatL1H-vaccinated mice than in the infected control mice indicating a lower degree of liver damage. This study demonstrated a high potential of FgCatL1H vaccine, and its efficacy is currently being studied in the larger economic animals.

The in vitro anthelmintic effects of plumbagin on newly excysted and 4-weeks-old juvenile parasites of Fasciola gigantica.

The effect of plumbagin (PB, 5-hydroxy-2-methyl-1,4-naphthoquinone) against newly excysted juveniles (NEJs) and 4-weeks-old immature parasites of Fasciola gigantica were compared with triclabendazole (TCZ). The anthelmintic efficacy of 1, 10 and 100µg/ml of PB or TCZ following incubation in vitro for 1-24h was compared using a combination of relative motility (RM), survival index (SI) and larval migration inhibition (LMI) assays for parasite viability. The RM and SI values of the PB-treated group decreased at a more rapid rate than the TCZ-treated group. For NEJs, the decreased RM values were first observed at 1h incubation with 1µg/ml PB, and 90% of flukes were killed at 24h. In contrast, in TCZ-treated groups a 10-fold higher concentration of TCZ (10µg/ml) resulted in only 9% dead parasites after 24h incubation. In 4-weeks-old juvenile parasites, PB reduced the RM value at 10µg/ml with 100% of flukes dead after 3h, while TCZ decreased RM values at the concentration of 100µg/ml but with only 5% of flukes killed at 24h. NEJs treated with PB exhibited 88%, 99% and 100% of LMIs at the concentrations of 1, 10 and 100µg/ml, respectively. NEJs incubated with TCZ have an LMI of only 32% at the highest concentration of 100µg/ml. Similarly PB had a significantly greater killing of immature 4weeks juvenile stages than TCZ at all concentrations; however, 4-weeks-old juvenile parasites were more resistant to killing by PB or TCZ at all concentrations when compared to NEJs. Further studies were carried out to investigate the alterations of the parasite tegument by scanning electron microscope (SEM). PB caused similar tegumental alterations in 4-weeks-old juveniles as those observed in TCZ treatment but with greater damage at comparative time points, comprising of swelling, blebbing and rupture of the tegument, loss of spines, and eventual erosion, lesion and desquamation of the total tegument. These data indicate that PB had a greater fasciolicidal effect against immature stages of F. gigantica parasites than TCZ and warrant further studies for use as a potential new anthelmintic against Fasciola infections.

Vaccine potential of recombinant cathepsin B against Fasciola gigantica.

In Fasciola gigantica, cathepsin Bs, especially cathepsin B2 and B3 are expressed in early juvenile stages, and are proposed to mediate the invasion of host tissues. Thus they are thought to be the target vaccine candidates that can block the invasion and migration of the juvenile parasite. To evaluate their vaccine potential, the recombinant cathepsin B2 (rFgCatB2) and cathepsin B3 (rFgCatB3) were expressed in yeast, Pichia pastoris, and used to immunize mice in combination with Freund's adjuvant to evaluate the protection against the infection by F. gigantica metacercariae, and the induction of immune responses. Mice immunized with both recombinant proteins exhibited high percent of parasite reduction at 60% for rFgCatB2 and 66% for rFgCatB3. Immunization by both antigens induced continuously increasing levels of IgG1 and IgG2a with a higher level of IgG1 isotype, indicating the mixed Th1/Th2 responses with Th2 predominating. When examined individually, the higher levels of IgG1 and IgG2a were correlated with the lower numbers of worm recoveries. Thus, both cathepsin B2 and cathepsin B3 are plausible vaccine candidates whose potential should be further tested in large economic animals.

The anthelmintic effect of plumbagin on Schistosoma mansoni.

The anthelmintic effects of plumbagin (PB, 5-hydroxy-2-methyl-1,4-naphthoquinone) and praziquantel (PZQ) against adult Schistosoma mansoni in vitro were compared by estimating the relative motility (RM) values, survival indices (SI) and alterations of the tegument of flukes incubated in M-199 medium containing 1, 10 and 100 µg/ml of the drugs, at 1, 3, 6, 12 and 24 h. For the parasites incubated in 10 µg/ml, the RM values of the PB-treated group decreased at a more rapid rate than the PZQ-treated group. When incubated in 100 µg/ml all PB-treated flukes appeared immobile from 1 to 24 h when 91-100% died, while in the PZQ-treated group RM values were higher than that of PB and most flukes were still alive at 1-12 h, and at 24 h only 21% of flukes were killed. Furthermore, male parasites were more affected by PZQ than females as their RM values were significantly less than that of females at all doses. While in PB treatment, males and females showed less difference in response to the drug as their RM values were closer than those treated with PZQ. When observed by SEM, the tegument of untreated S. mansoni displayed no alteration, while in PB treated parasites it exhibited swelling, blebbing, loss of spines, disruption of tubercles and ridges, leading to erosion and lesion, exposure of the basal lamina, and sloughing of the tegument. PZQ induced similar tegumental changes as those observed in PB treatment but at longer incubation time and higher doses. These data indicated that PB had more anthelmintic effect on both sexes of adult S. mansoni than PZQ.

Paramphistomum cervi: the in vitro effect of plumbagin on motility, survival and tegument structure.

Paramphistomiasis causes enteritis and anemia in livestocks and result in substantial production and economic losses. It is considered a neglected tropical disease, with no effective trematodicidal compound for treatment. Plumbagin (PB), a compound founds to be rich in the roots of Plumbago indica, is a naphthoquinone derivatives which can induce oxidative stress in parasites. In this study we have evaluated the anthelmintic activity of PB against adult Paramphistomum cervi by incubating the parasites in M-199 medium containing 0.1, 1.0, 10 and 100 µg/ml of the PB, and albendazole (ABZ) at the concentration of 100 µg/ml as the positive control, for 3, 6, 12 and 24 h, using relative motility (RM) assay and observed by scanning electron microscopy (SEM). After 12 h exposure with 100 µg/ml ABZ, flukes showed decreased contraction and motility. At 24 h incubation they showed only active movement of some part of the body. The PB-treated flukes at all concentrations showed rapid decrease of motility at 3 h incubation. In 0.1, 1.0 and 10 µg/ml of PB, the RM values were decreased sharply from 3 to 12 h, and then they were killed since 12 h in the incubation with 10 µg/ml of PB. The highest parasite mortality was found as early as 3h when they were incubated with 100 µg/ml of PB. The morphological changes on the tegumental surface were similar in both flukes treated with ABZ and PB, which sequentially comprised of swelling, followed by blebbings that later ruptured, leading to the erosion and desquamation of the tegument syncytium. As the result, lesions were formed which exposed the basal lamina. The damage appeared more severe on the ventral than the dorsal surface, and earlier on the anterior part and lateral margins of middle third when compared to the posterior part of the parasites's bodies. The severity and rapidity of the damages were enhanced with increasing concentration of PB, which showed stronger activity than ABZ. Hence, PB has a potential to be an anthelmintic drug against adult P.cervi.