The geology and geophysics of Kuiper Belt object (486958) Arrokoth.

The Cold Classical Kuiper Belt, a class of small bodies in undisturbed orbits beyond Neptune, is composed of primitive objects preserving information about Solar System formation. In January 2019, the New Horizons spacecraft flew past one of these objects, the 36-kilometer-long contact binary (486958) Arrokoth (provisional designation 2014 MU69). Images from the flyby show that Arrokoth has no detectable rings, and no satellites (larger than 180 meters in diameter) within a radius of 8000 kilometers. Arrokoth has a lightly cratered, smooth surface with complex geological features, unlike those on previously visited Solar System bodies. The density of impact craters indicates the surface dates from the formation of the Solar System. The two lobes of the contact binary have closely aligned poles and equators, constraining their accretion mechanism.

A novel case of chronic conjunctivitis in a 58-year-old woman caused by Raoultella.

A 58-year-old woman presented to eye emergency with a chronic conjunctivitis which was diagnosed by laboratory microbiological testing to be due to the environmental pathogen Raoultella planticola. The organism was sensitive to Chloramphenicol and the patient made a rapid recovery on these drops. This is the first report of this organism infecting the eye.

Bilateral hand-assisted laparoscopic nephrectomy in adult polycystic kidney disease patients: a UK centre experience.

PURPOSE: We report our experience with bilateral hand-assisted laparoscopic nephrectomy in patients with adult polycystic kidney disease. MATERIALS & METHODS: Between November 2009 and November 2010, 3 patients with adult polycystic kidney disease underwent bilateral hand-assisted laparoscopic nephrectomy in our institution. Indications for bilateral nephrectomy included recurrent cyst hemorrhage, impaired gastrointestinal function and early satiety due to direct intestinal compression by large polycystic kidneys, and anatomical lack of space for future renal transplantation. We retrospectively reviewed the records of these patients and we are reporting our experience. RESULTS: All three patients successfully underwent bilateral hand-assisted laparoscopic nephrectomy with a mean operating time of 208 minutes (range 195 to 220). There were no conversions to open procedure. Blood loss was less than 100 ml in all cases. Mean renal unit size was of 2037 g (range 1798 to 2214). Hospital stay ranged from 10 to 12 days. One patient developed a chest infection postoperatively and suffered from a prolonged ileus. Another patient developed a retroperitoneal hematoma, which was treated conservatively. CONCLUSIONS: Bilateral hand-assisted laparoscopic nephrectomy is a feasible and safe procedure in adult polycystic kidney disease patients, which has potential benefits of a shorter hospital stay and reduced morbidity and mortality in comparison to open procedure.

Antimicrobial peptides expression by ocular surface cells in response to Acanthamoeba castellanii: an in vitro study.

AIMS: Antimicrobial peptides (AMPs) are natural effectors of the innate immune response. Much work has been done to study their response and effects on bacterial and viral infection. Little if any information is available in relation to protozoal infections. The aim of the study was to comprehensively study the gene expression of the ocular AMPs in human corneal limbal epithelial cells stimulated with Acanthamoeba castellanii (AC). METHODS: Human corneal limbal epithelial cells were exposed to AC at different time points, up to 9 h, the genomic profile of the AMPs were analysed at these time point using real time PCR. corneal limbal epithelial cells not infected with AC were used as controls. RESULTS: Seven of the eight studied AMPs showed statistically significant upregulation in gene expression. Human beta Defensin 3 (hBD3) showed a very significant 10-fold upregulation in the exposed cells and Ribonuclease-7 (RNase-7) showed a very early and consistent increase. Human beta Defensin 1 (hBD1) was the only downregulated AMP. CONCLUSIONS: The study data suggests a possible role of the AMPs in combating the amoebic infection at the ocular surface. Using AMPs singly or in combination is a promising avenue for further exploration in the treatment of the sight threatening Acanthamoeba keratitis.

Early bleb leak after trabeculectomy and prognosis for bleb failure.

AIM: To determine whether early bleb leak after MMC trabeculectomy affects intermediate intraocular pressure (IOP) outcome. METHODS: Retrospective case note review. All cases of MMC trabeculectomy with at least 1-year follow-up were included. Cases where a bleb leak occurred within the first month were identified. All cases without an early bleb leak formed the control group. Patient demographics and clinical factors were analysed to determine any factors predisposing to bleb leakage. IOPs were compared for 1 year postoperatively and final follow-up. RESULTS: A total of 119 trabeculectomies were included. Of these 27 (22.7%) had an early bleb leak. The remaining 92 cases formed the control group. Mean age of cases was 70.7 years. Mean follow-up time was 19.5 months. Mean time of detection of the bleb leak was 9 days (range 1-21 days). Four cases (14.8%) were managed by primary resuturing. Thirteen cases (48.1%) were managed conservatively with a bandage contact lens. Ten cases (37.0%) resolved with expectant management. There was no statistically significant difference between the two groups with regards to IOP measurement at any time point. Intervention rates were similar with regards to bleb massage, 5-fluorouracil injection, and needling revision. No factors were identified between the two groups that predisposed to bleb leaks occurring. CONCLUSION: Our data suggest that early bleb leak is not a poor prognostic indicator for intermediate bleb survival and IOP control in patients undergoing MMC trabeculectomy. No additional bleb manipulations compared with the control group were required to achieve a satisfactory IOP outcome.

Choroidal detachment in perforated corneal ulcers: frequency and management.

AIMS: To determine the frequency of choroidal detachment (CD) in eyes with non-traumatic corneal ulcer perforation and, also, to assess the efficacy and safety of cyanoacrylate glue in sealing corneal perforations. METHODS: 18 eyes of 17 patients were studied. Inclusion criterion was any patient with a non-traumatic perforated corneal ulcer. All patients had a thorough history taken and complete ophthalmic examination including B-scan ultrasonography. Patient demographics, presence of CD, and efficacy of corneal gluing were assessed. RESULTS: Eight of the 18 eyes (44%) were documented to have a CD. Among perforations of >2 mm2, six eyes (75%) were documented to have CD compared with two eyes (20%) with perforations of

An uncommonly serious case of an uncommon sport injury.

BACKGROUND: A 55 year old man sustained a severe ocular injury when hit by a cricket ball even though he was wearing a helmet. METHODS: A suprachoroidal haemorrhage was drained and dense intravitreal blood was removed. An inferior buckle was applied with the use of intraocular gas. A macular haemorrhage resolved slowly. RESULTS: Despite several surgical procedures over 1.5 years, the final visual acuity of the patient was only 6/60 because of a dense macular scar. CONCLUSIONS: Helmets worn as protection when playing cricket need to be designed better and be of better material. Eye protection should be worn at all levels of play.

Some biochemical effects of long term oral contraceptive therapy on Egyptian females living in rural areas.

PIP: The serum activity of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and alkaline phosphatase, serum nilirubin (total, direct and indirect), serum proteins (total, albumin, alpha 1, alpha 2, beta and gamma globulins), serum glycoproteins (glyco-albumin, alpha 1, alpha 2, beta and glycoglobulins) and serum lipoproteins (alpha,pre beta, beta and chylomicrons) were studied in 131 Egyptian females receiving either 1 of 2 types of oral contraceptives. These parameters were evaluated before and after 6 and 12 months of continuous use of either 1) mg lynestrenol + 0.05 mg ethinyl estradiol) or (0.5 mg lynestrenol). All these biochemical entities remained within normal limits except serum albumin which showed a significant decrease from the pretreatment level. This decrease could be attributed to a decreased rate of albumin synthesis. Since the liver is the main organ for albumin synthesis, the reduction in albumin might indicate a possible deleterious effect of the hormones on the liver. The determination of the albumin level in the serum may serve as an index to the effect of contraceptive hormones on the liver. Tables for the mean and standard deviation values of studied parameters for group 1 and group 2 before and after 6 and 12 months of continuous use of the combined pill and the minipill are included.^ieng

Effect of oral contraceptives on some biochemical aspects in bilharzial Egyptian females living in rural areas.

PIP: The serum activity of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, and alkaline phosphatase; serum proteins (total, albumin, alpha-1, alpha-2, B and gamma globulins); glycoproteins (glycoalbumin, alpha-1, alpha-2, B and gamma glycoglobulins) and lipoproteins (alpha-, pre B, B and chylomicrons) were studied in 42 bilharzial Egyptian females with hepatic or hepatosplenic affections. These parameters were evaluated before and after 6 and 12 months of continuous use of either a combined pill (0.05 mg ethinyl estradiol + 1 mg lynestrenol) or a minipill (0.5 mg lynestrenol). All these biochemical entities remained within the normal limits except serum albumin and total serum proteins which showed significcant decreases after 6 and 12 months use of either contraceptive. The decrease of serum albumin could be attributed to a decreased rate of its synthesis. No significant increase in globulins was observed. Therefore a significant decrease in total proteins occurred. The decrease of serum albumin during the use of either contraceptive had previously been recorded by the authors in normal females living under the same socioeconomic status as the cases in this study. The same decrease in serum albumin had previously been recorded in non Egyptian females. The determination of albumin level in the serum may serve as an index to the effect of contraceptive hormones on the liver. In contradistinction to the finding in normal cases, alpha-1 glycoprotein failed to increase in response to the contraceptive hormones. This finding may indicate an inadequate response of the liver in bilharzial females to the effect of these hormones.^ieng