Mid-infrared emissivity of partially dehydrated asteroid (162173) Ryugu shows strong signs of aqueous alteration.

The near-Earth asteroid (162173) Ryugu, the target of Hayabusa2 space mission, was observed via both orbiter and the lander instruments. The infrared radiometer on the MASCOT lander (MARA) is the only instrument providing spectrally resolved mid-infrared (MIR) data, which is crucial for establishing a link between the asteroid material and meteorites found on Earth. Earlier studies revealed that the single boulder investigated by the lander belongs to the most common type found on Ryugu. Here we show the spectral variation of Ryugu's emissivity using the complete set of in-situ MIR data and compare it to those of various carbonaceous chondritic meteorites, revealing similarities to the most aqueously altered ones, as well as to asteroid (101955) Bennu. The results show that Ryugu experienced strong aqueous alteration prior to any dehydration.

Effects of microwave radiation on house dust mites, Dermatophagoides pteronyssinus and Dermatophagoides farinae (Astigmata: Pyroglyphidae).

Dermatophagoides pteronyssinus and Dermatophagoides farinae mites are commonly found in house dust, and are important sources of allergens affecting humans. Various approaches to killing the mites have been examined. This study investigated the mortalities of adult mites exposed to 2,450 MHz microwave radiation produced by 3 ovens at various exposure times and power settings. The ovens all had 3 power settings. The average maximum water temperatures generated at high, medium and low power settings were 99.4 +/- 0.2, 84.1 +/- 0.4 and 44.8 +/- 0.9 degrees C, respectively. At high and medium settings, there was 100.0% mortality in both species when exposed for 300 seconds. The mean mortality rates at low power were 10.8 +/- 0.7% for D. pteronyssinus and 9.7 +/- 2.6% for D. farinae. When mites were exposed in the presence of culture media, the mortality rates decreased with increasing weight of media. The mean mortality with the largest amount of media tested at high power setting was 61.4%.

Burst firing induces postsynaptic LTD at developing mossy fibre-CA3 pyramid synapses.

Synaptic development is an activity-dependent process utilizing coordinated network activity to drive synaptogenesis and subsequent refinement of immature connections. Hippocampal CA3 pyramidal neurons (PYRs) exhibit intense burst firing (BF) early in development, concomitant with the period of mossy fibre (MF) development. However, whether developing MF-PYR synapses utilize PYR BF to promote MF synapse maturation remains unknown. Recently, we demonstrated that transient tonic depolarization of postsynaptic PYRs induces a persistent postsynaptic form of long-term depression (depolarization-induced long-term depression, DiLTD) at immature MF-PYR synapses. DiLTD induction is NMDAR independent but does require postsynaptic Ca(2+) influx through L-type voltage gated Ca(2+) channels (L-VGCCs), and is expressed as a reduction in AMPAR function through the loss of GluR2-lacking AMPARs present at immature MF-PYR synapses. Here we examined whether more physiologically relevant phasic L-VGCC activation by PYR action potential (AP) BF activity patterns can trigger DiLTD. Using combined electrophysiological and Ca(2+) imaging approaches we demonstrate that PYR BF effectively drives L-VGCC activation and that brief periods of repetitive PYR BF, produced by direct current injection or intrinsic network activity induces NMDAR-independent LTD by promoting Ca(2+) influx through the activated L-VGCCs. This BF induced LTD, just like DiLTD, is specific for developing MF-PYR synapses, is PICK1 dependent, and is expressed postsynaptically. Our results demonstrate that DiLTD can be induced by phasic L-VGCC activation driven by PYR BF, suggesting the engagement of natural PYR network activity patterns for MF synapse maturation.

Morphology of Glycycometus malaysiensis, a domestic mite in Malaysia.

Glycycometus malaysiensis is an allergenic domestic mite found in houses. G. malaysiensis is known to be highly similar to and is often mistaken as Blomia tropicalis, one of the major house dust mite species that causes asthma and allergic diseases in many tropical and subtropical regions. It was also suggested that these mites cross-react with each other and that the prevalence of G. malaysiensis might be higher than previous reports. A review on the taxonomic keys as well as light and scanning electron micrographs of G. malaysiensis are presented to appreciate the fine morphological structures of G. malaysiensis. The mouth, setae, legs (trochanter, femur, genu, tibia and tarsus) and the sexual organs (genital openings, genital setae and genital suckers) of G. malaysiensis are outlined. The morphology of G. malaysiensis is also compared with that of B. tropicalis to delineate the key features for the differentiation between these two mite species.

The effectiveness of ICSI versus conventional IVF in couples with non-male factor infertility: study protocol for a randomised controlled trial.

STUDY QUESTIONS: Does ICSI result in a higher live birth rate as compared with conventional IVF in couples with non-male factor infertility? WHAT IS KNOWN ALREADY: ICSI is primarily indicated for severe male factor infertility. While the use of ICSI for couples with non-male factor infertility has been increasing worldwide, this is not supported by data from randomised controlled trials. Evidence from non-randomised studies suggest no benefit from ICSI compared with conventional IVF in non-male factor infertility, if not a harm. STUDY DESIGN SIZE DURATION: This randomised, open-label, multi-centre trial aims to compare the effectiveness of one ICSI cycle and one conventional IVF cycle in infertile couples with non-male factor infertility. A total of 1064 couples will be randomly allocated to an ICSI group and a conventional IVF group. The estimated duration of the study is 30 months. PARTICIPANTS/MATERIALS SETTING METHODS: Eligible couples are those whose husbands' total sperm count and motility are normal, have undergone ≤2 previous IVF/ICSI attempts, use antagonist protocol for ovarian stimulation, agree to have ≤2 embryos transferred and are not participating in another IVF study at the same time. Women undergoing IVM cycles, using frozen semen or having a poor fertilisation (≤25%) in previous cycle will not be eligible. Couples will be randomised to undergo ICSI or conventional IVF (1:1) with ongoing pregnancy resulting in live birth after the first embryo transfer of the started treatment cycle as the primary endpoint. All analyses will be conducted on an intention-to-treat basis. Effect sizes will be summarised as relative risk (RR), with precision evaluated by 95% CIs. STUDY FUNDING/COMPETING INTERESTS: All authors declare having no conflict of interests with regards to this trial. This work was supported by a grant from MSD [MISP #57508]. TRIAL REGISTRATION NUMBER: NCT03428919. TRIAL REGISTRATION DATE: 8 February 2018. DATE OF FIRST PATIENT'S ENROLMENT: 16 March 2018.

Images from the surface of asteroid Ryugu show rocks similar to carbonaceous chondrite meteorites.

The near-Earth asteroid (162173) Ryugu is a 900-m-diameter dark object expected to contain primordial material from the solar nebula. The Mobile Asteroid Surface Scout (MASCOT) landed on Ryugu's surface on 3 October 2018. We present images from the MASCOT camera (MASCam) taken during the descent and while on the surface. The surface is covered by decimeter- to meter-sized rocks, with no deposits of fine-grained material. Rocks appear either bright, with smooth faces and sharp edges, or dark, with a cauliflower-like, crumbly surface. Close-up images of a rock of the latter type reveal a dark matrix with small, bright, spectrally different inclusions, implying that it did not experience extensive aqueous alteration. The inclusions appear similar to those in carbonaceous chondrite meteorites.

Residual activity of benzyl benzoate against Dermatophagoides pteronyssinus (Acari: Pyroglyphidae).

The residual effect of a commercial spray containing 2.0% benzyl benzoate against Dermatophagoides pteronyssinus was evaluated in the laboratory. Filter papers treated with benzyl benzoate were dried for 2 hours and placed in Petri dishes. Adult mites were then added and mortality was assessed following 24 hour contact and at succeeding 4 weeks intervals up to week 28 post-treatment using the same treated filter papers. There was 100% mortality at 24 hours post-treatment, declining progressively to 71% by week 28. Probit analysis estimated a median lethal time (LT50) of 59 weeks.

Ticks (Ixodidae) and other ectoparasites in Ulu Muda Forest Reserve, Kedah, Malaysia.

A survey of ticks and other ectoparasites was carried out during a national biodiversity scientific expedition at Ulu Muda Forest Reserve, Kedah, Malaysia from 23-29 March 2003. A total of 161 animals comprising 20 species of birds, 16 species of bats, six species of non-volant small mammals and 12 species of reptiles were examined for ticks and other ectoparasites. From these animals, nine species in five genera of ticks, 10 species in two families of Mesostigmatid mites and five species of chiggers were collected. Three of the ectoparasitic species found, Dermacentor auratus, Ixodes granulatus and Leptotrombidium deliense are of known public health importance. This survey produced the first list of ticks and other ectoparasites in the forest reserve and the third study of ectoparasites in Kedah. Fourteen species of these ectoparasites are new locality records.

Live birth rate after human chorionic gonadotropin priming in vitro maturation in women with polycystic ovary syndrome.

BACKGROUND: In vitro maturation (IVM) has some advantages over conventional in vitro fertilization (IVF), particularly in polycystic ovary syndrome (PCOS) where the risk of ovarian hyperstimulation is high. We studied the live birth rate in a large series of PCOS women undergoing human chorionic gonadotropin (hCG)-priming IVM. METHODS: This retrospective study included women with PCOS aged 18-42 years undergoing IVM with hCG priming. We reported live birth rate after the first embryo transfer and cumulative live birth rate from embryos obtained in the IVM cycle. We also performed logistic regression to assess which factors predicted number of oocytes and live birth. RESULTS: We included 921 women (age 28.9±3.5 years, body mass index 21.8±3.1 kg/m2, infertility duration 3.7±2.6 years, 81% primary infertility, 88% first IVF attempt, 94% ovulation induction failure). Live birth rate after the first embryo transfer was 31.7%, with a cumulative live birth rate from the cycle of 33.7%. High anti-Müllerian hormone levels predicted a high number of oocytes and a high oocyte maturation rate while the opposite was the case when luteinizing hormone levels were high. CONCLUSIONS: In women with PCOS, hCG priming IVM was feasible and resulted in acceptable live birth rates.

Laboratory contact and topical evaluations of household disinfectants against house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae (Acari: Pyroglyphidae).

The contact and topical activity of two household disinfectants containing chloroxylenol and benzyl chlorophenol against, Dermatophagoides pteronyssinus and Dermatophagoides farinae mites were evaluated in the laboratory. For contact activity, 30 adult mites were placed for 24 hrs on Whatman No. 1 filter paper impregnated with disinfectant. For topical activity, each disinfectant was directly applied to individual body of all 30 dust mites and observed for 24hrs. All treatments were replicated 12 times. Chloroxylenol disinfectant was found to be more effective compared to benzyl chlorophenol disinfectant in killing pyroglyphid mites.

A survey of ectoparasites in Gunung Stong Forest Reserve, Kelantan, Malaysia.

A survey of ticks and other ectoparasites was carried out during a national biodiversity scientific expedition at Gunung Stong Forest Reserve, Kelantan, Malaysia from 23-29 May 2003. A total of 272 animals comprised of 12 species of birds, 21 species of bats, 7 species of rodents and 2 species of insects were examined for ticks and other ectoparasites. From these animals, 5 species in 4 genera of ticks; 7 species in 2 families of Mesostigmatid mites and 5 species of chiggers were collected. Among the ectoparasites found were Ixodes granulatus and Leptotrombidium deliense, which are of known medical importance. A tick island consisting of 10 nymphal stages of Dermacentor spp was observed feeding on Rattus tiomanicus.

The first graduates in 1910.

The Medical School in Singapore was founded on 3 July 1905 and named the Straits and Federated Malay States Government Medical School. There were 23 students in the first enrollment; 16 students attended the full course, while 7 attended a 2-year course for hospital assistants. The pioneer group of 7 that graduated in May 1910 (the Magnificent Seven) consisted of Drs Chen Su Lan, Edwin Williborod deCruz, and John Gnanapragasam from Singapore; Drs Willie Carnegie and Mark W Chill from Penang; Dr SR Krishnan from Seramban and Dr John Scott Lee from Ipoh. In December 1910, a further 6 students graduated. Of this first batch of 13 graduates in 1910, we describe the careers of 6; no records exist of the remaining 7.

Sero-prevalence study of IgE responses to allergens from Malaysian house dust (HDM) and storage mites (SM).

Allergens of Dermatophagoides and Blomia species are well-characterized but not for other species. This study was conducted to determine the prevalence of allergic sensitization to house dust (HDM) and storage mites (SM). One hundred adult subjects (aged ≥ 18) were recruited. The mite specific IgE of all allergic subjects were higher compared with healthy subjetcs despite being not statistically significant except for D. farinae and G. malaysiensis. The mean serum IgE levels against HDM and SM for allergic subjects were significantly higher compared with those in healthy subjects. They were mainly sensitized to Dermatophagoides farinae (35%) and Glycycometus malaysiensis (37%). Immunoblots revealed not all allergic subjects showed positive immuno-reactivity against the mites tested. Single or multiple bands were observed for different species. The subjects were commonly sensitized to Group 2 (9-12 kDa), 10 (38 kDa) and 18 (40-48 kDa) allergens. Twenty-one out of 60 allergic subjects were sensitized to either one or more species. The majority of them (71%) were sensitized to single species. The allergic subjects were mainly sensitized to D. pteronyssinus, followed by Tyrophagus putrecentiae and Aleuroglyphus ovatus. Seven were solely sensitized to HDM while 10 were solely sensitized to SM. Four subjects were sensitized to both. Pre-adsorption study revealed no cross-reactivity. There was difference between the prevalence and reactivity to allergens of HDM and SM in these subjects. Both ELISA and immunoblot did not correlate well but can complement each other in improving the detection of mite allergens to the species level.

Expression of recombinant proteins of Orientia tsutsugamushi and their applications in the serodiagnosis of scrub typhus.

In this study, recombinant proteins that encompassed the AD I-AD III regions of 56 kDa immunodominant gene of 2 Orientia tsutsugamushi (OT) serotypes; Gilliam and TA763 were expressed in Escherichia coli. Both recombinant proteins exhibited serologic cross-reactivity with the rabbit antisera against various OT serotypes, as evaluated by enzyme-linked immunosorbent assay (ELISA), but not against other rickettsial species, including Rickettsia typhi, R. prowazekii and TT118 SFG rickettsiae. The feasibility of using the recombinant proteins as a diagnostic reagent was further evaluated by ELISA using sera from blood donors and scrub typhus patients. The results suggested a higher affinity of the antihuman IgM than IgG with both recombinant proteins. The IgM ELISA findings were agreeable with the results of indirect immunoperoxidase (IIP) assay especially with sera of high antibody (1:1600). However, more than one antigen are probably needed for development of an effective assay for serodiagnosis of scrub typhus in endemic areas.

Antibodies to Orientia tsutsugamushi, Rickettsia typhi and spotted fever group rickettsiae among febrile patients in rural areas of Malaysia.

A serosurvey was conducted in 1995-97 among 1596 febrile patients from 8 health centres in Malaysia for antibodies against Orientia tsutsugamushi (OT), Rickettsia typhi (RT) and TT118 spotted fever group rickettsiae (SFGR) by using an indirect immunoperoxidase assay. A total of 51.4% patients had antibody against at least 1 of those rickettsiae. Antibody to SFGR was most prevalent (42.5%), followed by RT (28.1%) and OT (24.9%). The seroprevalences of antibodies to SFGR, RT or OT alone were 12.4, 3.6 and 4.3%, respectively. Antibodies against more than 1 species of rickettsiae were presence in 31.1% of the patients, suggesting the possibility of co-infection, previous exposures or serological cross-reactivities. Seroprevalence of the various rickettsiae varied according to locality, with SFGR antibodies being the most prevalent in most areas. There was no significant association of prevalence of rickettsial antibody with gender. The seroprevalence of OT, SFGR and RT increased with patient age but an increase of antibody titre with age was not significant. Those working in the agricultural sectors had significantly higher seroprevalence of OT, SFGR and RT than those not related with agricultural activities. Scrub typhus remains a public health problem with an estimated annual attack rate of 18.5%. Tick typhus and murine typhus as shown in this serosurvey appear much more widespread than scrub typhus in this country.

Efficacy of three pyrethroids against Leptotrombidium fletcheri (Acari: Trombiculidae) infected and noninfected with scrub typhus.

Toxicities of three pyrethroids, d-phenothrin, decamethrin, and permethrin, were evaluated in the laboratory against Leptotrombidium fletcheri (Womersley & Heaslip). The susceptibilities between populations of the species infected and noninfected with scrub typhus were investigated. The three pesticides exhibited different toxicities to the chiggers. D- phenothrin was the most toxic, followed by decamethrin, then permethrin. There were no significant differences between susceptibilities of the infected and noninfected populations. Log-probit regression lines indicated that the species was most sensitive to increasing concentrations of d-phenothrin and least sensitive to permethrin. The results show that the three pesticides are potential candidates for chemical control of L. fletcheri. It may be possible in the future to conduct similar bioassays only with the noninfected population, thus reducing risk of infection to workers conducting the bioassays. Similarly, there may not be a need to separate field-collected chiggers into the two populations before performing the bioassays.

Development and evaluation of dot-immunobinding assay for detection of scrub typhus infection in Leptotrombidium fletcheri (Acari: Trombiculidae).

A dot-immunobinding assay (DIBA) was compared with a direct fluorescent antibody technique (DFAT) for the detection of Rickettsia tsutsugamushi infection in Leptotrombidium fletcheri (Womersley & Heaslip). Laboratory colonies of infected and noninfected chiggers were examined. The relative proportions of positive, negative, and indeterminate results were significantly different between DIBA and DFAT for infected but not for noninfected chiggers. DIBA was more sensitive and had a better negative predictive value and a lower false negative percentage than DFAT. It was concluded that DIBA is a suitable alternative to DFAT for detecting scrub typhus infection in chiggers.

Detection and characterization of Rickettsia tsutsugamushi (Rickettsiales: Rickettsiaceae) in infected Leptotrombidium (Leptotrombidium) fletcheri chiggers (Acari: Trombiculidae) with the polymerase chain reaction.

We developed a method for detecting and characterizing the DNA of Rickettsia tsutsugamushi in chiggers (larval trombiculid mites) by polymerase chain reaction (PCR). Three procedures for extracting DNA from frozen chiggers were compared by evaluating the yield of PCR amplicand obtained with nine oligonucleotide primer pairs derived from the rickettsial 22 kD, 47 kD, groESL, 56 kD, and 110 kD antigen genes. Although extracts and primer pairs differed in amplification efficiency, R. tsutsugamushi DNA was successfully detected in extracts of colonized infected Leptotrombidium (Leptotrombidium) fletcheri (Wormersley & Heaslip) chiggers and in uninfected chigger extracts seeded with known amounts of Karp-strain rickettsiae. The 22 kD gene restriction fragment length polymorphisms (RFLP) observed in PCR amplicands from five rickettsial isolates obtained from the infected chigger colony over a 26-yr period were identical to those of PCR amplicands derived directly from infected chiggers taken from the same colony. This suggests that stable transmission of R. tsutsugamushi occurs in mites (62 generations), and isolates encompass the full genetic heterogeneity found in the chigger. PCR/RFLP analysis is an important new tool for investigating the complex epidemiology of scrub typhus rickettsiae in their mite vectors.

Our dilemma: the self-marginal people.

Cultural diversity is nowadays a common phenomenon in most developed countries. Its impact is felt in daily life, as well as in health care settings. Hospital del Mar, due to its geographical location, receives some of the 34.7% of immigrants from a varied cultural background. Endeavours are made to promote cultural awareness among staff and to facilitate communication. However, a Spanish Gypsy group, albeit not immigrants, are by large the problematic cultural group. A questionnaire study was conducted to validate the difficulty in treating these Gypsies versus migrant patients. The questionnaire was distributed to different health care professionals in the hospital. The result is not surprising. The problems encountered with the migrant patients are mainly due to language barrier. Concerning these Gypsies who speak fluent Spanish, the problems are by far more extensive. These are often generated by their abiding cultural values, distinctive lifestyle, low educational level and rejection of the shared norms of the majority. Any attempt to encourage adherence to hospital rules are often futile as a result of the gypsies' negative attitudes. Staff have expressed occasional feelings of weariness when dealing with such situations.

Laboratory evaluation of two commercial repellants against Leptotrombidium fletcheri (Acari: Trombiculidae).

Two commercial repellants were evaluated in the laboratory against Leptotrombidium fletcheri chiggers. The active ingredient in one was DEET and in the other was citrus oil. Excito-toxicity effect was studied and it was determined by the time ("escape time") chiggers took to move off filter papers treated with the repellants. All chiggers exposed on filter papers treated with DEET died and did not move off the treated papers. None of the chiggers that were placed on papers treated with citrus oil were killed. Escape times on papers treated with a 2-sec spray of citrus oil were longer than those for the 4- and 8-sec sprays. The weights of citrus oil deposited increased with increasing spray times. Electron microscopy showed that the repellants had no effect on the texture of the filter papers. It was concluded that the spray containing DEET was more effective; however, both repellants should be further evaluated under field conditions for protection against chigger bites.