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Two new genera of tube-making spittlebugs (Hemiptera: Machaerotidae: Enderleiniini)

Bell AJ, Cryan JR

Zootaxa, 2013;3640:57-69.
PMID: 26000404

Two new monotypic spittlebug genera and their type species in the family Machaerotidae, subfamily Enderleiniinae, are described and illustrated: Labramachaerota korupa gen. & sp. n. (with type locality in Cameroon) and Kyphomachaerota maaia gen. & sp. n. (with type locality in Sarawak, Malaysia).
Wallace's line, Wallacea, and associated divides and areas: history of a tortuous tangle of ideas and labels

Ali JR, Heaney LR

Biol Rev Camb Philos Soc, 2021 06;96(3):922-942.
PMID: 33502095 DOI: 10.1111/brv.12683

Due to its position between the highly distinct Oriental and Australasian biogeographical realms, much effort has been spent demarcating associated separations and transitions in the faunal assemblages of the Indo-Australian Archipelago. Initially, sharp boundary lines were proposed, with the earliest dating from the mid-1800s. Notably, the one published by Alfred R. Wallace in 1863, based upon land-mammal and land-bird distributions, has since achieved iconic status and today its significance is recognized well beyond the confines of the biogeography community. Over the next four decades many such divides were engraved onto plates and inked onto charts of SE Asia using additional information, different organisms or other criteria. However, it became apparent that, as Wallace had noted, all such lines were to some degree permeable, and by the 1880s transition zones were being put forward instead; the label 'Wallacea' was introduced in 1924. Interestingly, the last decade has seen new divides and sub-regions being proposed, some departing markedly from earlier offerings. Although currently there is general agreement regarding much of the terminology associated with both the lines and the areas, the record of publication indicates that this consensus has emerged obliquely, and in some cases is weakly founded. This review does not present new data nor new analyses; rather it summarizes the development of ideas and reflects upon attendant issues that have emerged. After reviewing the key proposals, recommendations are presented that should in future alleviate perceived difficulties or inadequacies. Reference to specific divides must be true to their original definitions; there are many instances where the secondary literature has portrayed them incorrectly and with some this has rippled through into later publications. Moreover, Wallace's 1863 line is not the one that he finally settled upon (in 1910); its path around Sulawesi was transferred from the west to the east of the Island. Ideally, Huxley's divide (1868) should carry his name rather than Wallace's; the latter never accepted the proposition. Lydekker's Line (1896) ought to be labelled the Heilprin-Lydekker Line in recognition of Angelo Heilprin's 1887 contribution. Concerning transition zones, ideally Wallacea should correspond to its original 1924 description, which incorporated the Philippine islands bar the Palawan group. Notably, though, a smaller form (introduced by Darlington in 1957, used frequently from 1998 onwards) in which all of the Philippine islands are excluded is entrenched within the recent literature, but this is often without evident justification. It should also be recognized that the 'reduced' (=southern) Wallacea area was effectively defined by Heilprin in 1887, but was then labelled the 'Austro-Malaysian Transition Zone'. Finally, the application in recent years of modern analytical techniques has not led to a consensus view on where the lines/areas should run/be placed; with such a large, diverse set of organisms, each with differing histories, this is perhaps not surprising.
Fulltext A Rare Case of Spinal Extradural Arachnoid Cyst with Cord Compression

Lin LC, Jason R

Asian J Neurosurg, 2018 4 24;13(2):468-470.
PMID: 29682063 DOI: 10.4103/ajns.AJNS_310_16

Spinal extradural arachnoid cysts are rare lesions which typically involve the thoracic spine and are an asymptomatic condition of unknown origin. They may also produce symptoms by compressing the spinal cord or nerve roots. Surgery is the treatment of choice in such lesions, but asymptomatic patients can be managed conservatively. We present a case of symptomatic, probable traumatic origin, spinal arachnoid cyst at our center in Hospital Kuala Lumpur, Malaysia. Magnetic resonance imaging spine showed well-defined, nonenhancing extradural cystic lesion from T5 to T6 vertebrae level compressing spinal cord anteriorly. The patient underwent T5, T6 laminoplasty, T4 partial laminectomy and excision of the cyst. Histologically, the cyst wall comprised of collagen and meningothelial cells. This surgical intervention achieved neurological improvement in terms of motor power in our follow-up of this patient.
Biomimetic bacterial and viral-based nanovesicles for drug delivery, theranostics, and vaccine applications

Loo YS, Bose RJ, McCarthy JR, Mat Azmi ID, Madheswaran T

Drug Discov Today, 2021 04;26(4):902-915.
PMID: 33383213 DOI: 10.1016/j.drudis.2020.12.017

Smart nanocarriers obtained from bacteria and viruses offer excellent biomimetic properties which has led to significant research into the creation of advanced biomimetic materials. Their versatile biomimicry has application as biosensors, biomedical scaffolds, immobilization, diagnostics, and targeted or personalized treatments. The inherent natural traits of biomimetic and bioinspired bacteria- and virus-derived nanovesicles show potential for their use in clinical vaccines and novel therapeutic drug delivery systems. The past few decades have seen significant progress in the bioengineering of bacteria and viruses to manipulate and enhance their therapeutic benefits. From a pharmaceutical perspective, biomimetics enable the safe integration of naturally occurring bacteria and virus particles to achieve high, stable rates of cellular transfection/infection and prolonged circulation times. In addition, biomimetic technologies can overcome safety concerns associated with live-attenuated and inactivated whole bacteria or viruses. In this review, we provide an update on the utilization of bacterial and viral particles as drug delivery systems, theranostic carriers, and vaccine/immunomodulation modalities.
Fulltext Hand Sanitizers: A Review on Formulation Aspects, Adverse Effects, and Regulations

Jing JLJ, Pei Yi T, Bose RJC, McCarthy JR, Tharmalingam N, Madheswaran T

Int J Environ Res Public Health, 2020 05 11;17(9).
PMID: 32403261 DOI: 10.3390/ijerph17093326

Hand hygiene is of utmost importance as it may be contaminated easily from direct contact with airborne microorganism droplets from coughs and sneezes. Particularly in situations like pandemic outbreak, it is crucial to interrupt the transmission chain of the virus by the practice of proper hand sanitization. It can be achieved with contact isolation and strict infection control tool like maintaining good hand hygiene in hospital settings and in public. The success of the hand sanitization solely depends on the use of effective hand disinfecting agents formulated in various types and forms such as antimicrobial soaps, water-based or alcohol-based hand sanitizer, with the latter being widely used in hospital settings. To date, most of the effective hand sanitizer products are alcohol-based formulations containing 62%-95% of alcohol as it can denature the proteins of microbes and the ability to inactivate viruses. This systematic review correlated with the data available in Pubmed, and it will investigate the range of available hand sanitizers and their effectiveness as well as the formulation aspects, adverse effects, and recommendations to enhance the formulation efficiency and safety. Further, this article highlights the efficacy of alcohol-based hand sanitizer against the coronavirus.
Fulltext Combating Intracellular Pathogens with Nanohybrid-Facilitated Antibiotic Delivery

Bose RJC, Tharmalingam N, Choi Y, Madheswaran T, Paulmurugan R, McCarthy JR, et al.

Int J Nanomedicine, 2020;15:8437-8449.
PMID: 33162754 DOI: 10.2147/IJN.S271850

BACKGROUND: Lipid polymer hybrid nanoparticles (LPHNPs) have been widely investigated in drug and gene delivery as well as in medical imaging. A knowledge of lipid-based surface engineering and its effects on how the physicochemical properties of LPHNPs affect the cell-nanoparticle interactions, and consequently how it influences the cytological response, is in high demand.
METHODS: Herein, we have engineered antibiotic-loaded (doxycycline or vancomycin) LPHNPs with cationic and zwitterionic lipids and examined the effects on their physicochemical characteristics (size and charge), antibiotic entrapment efficiency, and the in vitro intracellular bacterial killing efficiency against Mycobacterium smegmatis or Staphylococcus aureus infected macrophages.
RESULTS: The incorporation of cationic or zwitterionic lipids in the LPHNP formulation resulted in a size reduction in LPHNPs formulations and shifted the surface charge of bare NPs towards positive or neutral values. Also observed were influences on the drug incorporation efficiency and modulation of the drug release from the biodegradable polymeric core. The therapeutic efficacy of LPHNPs loaded with vancomycin was improved as its minimum inhibitory concentration (MIC) (2 µg/mL) versus free vancomycin (4 µg/mL). Importantly, our results show a direct relationship between the cationic surface nature of LPHNPs and its intracellular bacterial killing efficiency as the cationic doxycycline or vancomycin loaded LPHNPs reduced 4 or 3 log CFU respectively versus the untreated controls.
CONCLUSION: In our study, modulation of surface charge in the nanomaterial formulation increased macrophage uptake and intracellular bacterial killing efficiency of LPHNPs loaded with antibiotics, suggesting alternate way for optimizing their use in biomedical applications.
Fulltext Scaling up evidence-based approaches to tuberculosis screening in prisons

Charalambous S, Velen K, Rueda Z, Croda J, Herce ME, Shenoi SV, et al.

Lancet Public Health, 2023 Apr;8(4):e305-e310.
PMID: 36780916 DOI: 10.1016/S2468-2667(23)00002-6

People deprived of liberty have among the highest rates of tuberculosis globally. The incidence of tuberculosis is ten times greater than the incidence of tuberculosis in the general population. In 2021, WHO updated its guidance to strongly recommend systematic screening for tuberculosis in prisons and penitentiary systems. Which case-finding strategies should be adopted, and how to effectively implement these strategies in these settings, will be crucial questions facing ministries of health and justice. In this Viewpoint, we review the evidence base for tuberculosis screening and diagnostic strategies in prisons, highlighting promising approaches and knowledge gaps. Drawing upon past experiences of implementing active case-finding and care programmes in settings with a high tuberculosis burden, we discuss challenges and opportunities for improving the tuberculosis diagnosis and treatment cascade in these settings. We argue that improved transparency in reporting of tuberculosis notifications and outcomes in prisons and renewed focus and resourcing from WHO and other stakeholders will be crucial for building the commitment and investments needed from countries to address the continued crisis of tuberculosis in prisons.
Fulltext High shear in situ exfoliation of 2D gallium oxide sheets from centrifugally derived thin films of liquid gallium

Vimalanathan K, Palmer T, Gardner Z, Ling I, Rahpeima S, Elmas S, et al.

Nanoscale Adv, 2021 Oct 12;3(20):5785-5792.
PMID: 36132680 DOI: 10.1039/d1na00598g

A diversity of two-dimensional nanomaterials has recently emerged with recent attention turning to the post-transition metal elements, in particular material derived from liquid metals and eutectic melts below 330 °C where processing is more flexible and in the temperature regime suitable for industry. This has been explored for liquid gallium using an angled vortex fluidic device (VFD) to fabricate ultrathin gallium oxide (Ga2O3) sheets under continuous flow conditions. We have established the nanosheets to form highly insulating material and have electrocatalytic activity for hydrogen evolution, with a Tafel slope of 39 mV dec-1 revealing promoting effects of the surface oxidation (passivation layer).
Fulltext Hell's Gate globin I: an acid and thermostable bacterial hemoglobin resembling mammalian neuroglobin

Teh AH, Saito JA, Baharuddin A, Tuckerman JR, Newhouse JS, Kanbe M, et al.

FEBS Lett, 2011 Oct 20;585(20):3250-8.
PMID: 21925500 DOI: 10.1016/j.febslet.2011.09.002

Hell's Gate globin I (HGbI), a heme-containing protein structurally homologous to mammalian neuroglobins, has been identified from an acidophilic and thermophilic obligate methanotroph, Methylacidiphilum infernorum. HGbI has very high affinity for O(2) and shows barely detectable autoxidation in the pH range of 5.2-8.6 and temperature range of 25-50°C. Examination of the heme pocket by X-ray crystallography and molecular dynamics showed that conformational movements of Tyr29(B10) and Gln50(E7), as well as structural flexibility of the GH loop and H-helix, may play a role in modulating its ligand binding behavior. Bacterial HGbI's unique resistance to the sort of extreme acidity that would extract heme from any other hemoglobin makes it an ideal candidate for comparative structure-function studies of the expanding globin superfamily.
Building a tuberculosis-free world: The Lancet Commission on tuberculosis

Reid MJA, Arinaminpathy N, Bloom A, Bloom BR, Boehme C, Chaisson R, et al.

Lancet, 2019 Mar 30;393(10178):1331-1384.
PMID: 30904263 DOI: 10.1016/S0140-6736(19)30024-8
Congenital Titinopathy: Comprehensive Characterization of the Most Severe End of the Disease Spectrum

Coppens S, Deconinck N, Sullivan P, Smolnikov A, Clayton JS, Griffin KR, et al.

Ann Neurol, 2025 Jan 24.
PMID: 39853809 DOI: 10.1002/ana.27087

Congenital titinopathy has recently emerged as one of the most common congenital muscle disorders.
OBJECTIVE: To better understand the presentation and clinical needs of the under-characterized extreme end of the congenital titinopathy severity spectrum.
METHODS: We comprehensively analyzed the clinical, imaging, pathology, autopsy, and genetic findings in 15 severely affected individuals from 11 families.
RESULTS: Prenatal features included hypokinesia or akinesia and growth restriction. Six pregnancies were terminated. Nine infants were born at or near term with severe-to-profound weakness and required resuscitation. Seven died following withdrawal of life support. Two surviving children require ongoing respiratory support. Most cohort members had at least 1 disease-causing variant predicted to result in some near-normal-length titin expression. The exceptions, from 2 unrelated families, had homozygous truncating variants predicted to induce complete nonsense mediated decay. However, subsequent analyses suggested that the causative variant in each family had an additional previously unrecognized impact on splicing likely to result in some near-normal-length titin expression. This impact was confirmed by minigene assay for 1 variant.
INTERPRETATION: This study confirms the clinical variability of congenital titinopathy. Severely affected individuals succumb prenatally/during infancy, whereas others survive into adulthood. It is likely that this variability is because of differences in the amount and/or length of expressed titin. If confirmed, analysis of titin expression could facilitate clinical prediction and increasing expression might be an effective treatment strategy. Our findings also further-support the hypothesis that some near-normal-length titin expression is essential to early prenatal survival. Sometimes expression of normal/near-normal-length titin is due to disease-causing variants having an additional impact on splicing. ANN NEUROL 2025.