Southern ocean carbon and heat impact on climate

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

Broad responses and attitudes to having music in surgery (the BRAHMS study) - a South African perspective

BACKGROUND

Music is played in operating theatres (OTs) throughout the world, though controversy around its use exists. While some clinicians may find background music favourable to the theatre mood and a way to augment surgical performance, there is concern raised over its distracting and noise-creating properties.

METHODS

In this prospective observational study, between August and December 2021, 110 surgeons and registrars in South Africa responded to a survey investigating the way they use music, and their perceptions and attitudes towards its effect on the OT environment.

RESULTS

In this cohort, 66% were male, 29% were consultants and the most common age range was 30-39 years old. Eighty per cent of respondents reported that music was played at least "sometimes", with 74% reporting that they enjoyed it. Easy Listening was the most played and preferred genre followed by Top 40/Billboard hits. Overwhelmingly, respondents reported that background music in the OT improved temperament, focus, mood, and performance, though over a quarter felt it worsened communication. Thirty-one per cent of respondents reported that the choice of music depended on the type of operation, and 70% would turn music down or off during crises. Those who enjoyed music in their spare time were significantly more likely to enjoy music in the OT and perceive it positively.

CONCLUSION

This study provides a window into the surgeons' use of and attitudes to intraoperative music in South Africa. While overall, music is viewed positively by this cohort, some concerns remain regarding communication and distractedness. Further interventional and qualitative studies would be useful.

1515 A Survey on The Perceived Effect of Background Music on Intra-Operative Stress, Anxiety and Surgical Task Load On the Operating Surgeon

Introduction

Music is commonly played in operating theatres throughout the world though its use remains controversial. There is growing literature supporting the notion that playing background music can improve a surgeon’s task performance and reduce performance stress. We present findings from our survey of surgeons about their perceptions of the effect of intra-operative music on their stress levels.

Method

Surgeons and registrars from three different specialties – general, vascular, and paediatric surgery – in a single tertiary centre were surveyed on their views on the effect of music in theatre. Two instruments were used to assess parameters of stress: the modified 6-point state trait anxiety inventory (STAI-6) and the surgical task load index (SURG-TLX).

Results

There were 35 respondents across the three surgical specialties (78% response rate). Pop and “easy listening” were the most popular genres. A majority felt music improved their temperament (75%) and perceived stress (63%). 59% of respondents reported no to low perceived anxiety with music, compared with 31% reporting moderate and 9% high anxiety based on STAI-6 parameters. Regarding SURG-TLX parameters and music, respondents overall perceived feeling less anxious, rushed and mentally fatigued though more distracted.

Conclusions

Music is generally thought to have positive subjective effects on the theatre environment with regards to anxiety levels, temperament, perceived stress, and parameters within the surgical task load index. This is counterbalanced by a smaller group of respondents who felt that music can impair communication and increase distraction within theatre. Music used appropriately may reduce perceptions of stress in theatre.

A split-tattoo randomized Q-switched neodymium-doped yttrium-aluminium-garnet laser trial comparing the efficacy of a novel three-pass, one-session method with a conventional method in the treatment of blue/black tattoos in darker skin types

Tattoos with blue/black ink show good lightening of pigment after treatment with 1064 nm Q-switched (QS) neodymium-doped yttrium-aluminium-garnet (Nd:YAG) laser. In this randomized trial, we compared the efficacy of a novel three pass, one session procedure (R15 method) with a conventional method for treating blue/black tattoos in darker skin types. Tattoos were treated with 1064 nm QS Nd:YAG Laser with a spot size of 4 mm, fluence of 5 J/cm² and frequency of 5 Hz. The tattoo pigment lightening was comparable with both methods. Thread-like tattoos had significantly better pigment lightening with fewer side effects than the broad band-like tattoos. We would like to recommend the R15 method of the QS Nd:YAG laser for thread-like tattoos, which can save patients' time, cut short the frequency of their hospital visits and, more importantly, decrease the cost involved in it.

504 Can Measuring Heart Rate Variability in The Operating Surgeon Provide Insight into Intra-Operative Stress? A Literature Review and Direction for Research

Introduction

Stress affects the internal environment of the operating surgeon. Examining ways to mitigate this could prove important to the health of both surgeon, and patients.

Heart rate variability (HRV) is emerging as a novel, validated measure of autonomic nervous system (ANS) function with developing accessible and non-invasive technologies. HRV parameters correlate to ANS function and can be used to measure responses to various stimuli.

Method

A search strategy was developed to identify 23 articles that matched inclusion criteria. These included data collected intra-operatively with ambulatory monitoring, in simulated settings and one systematic review.

Results

Several studies found increased sympathetic response in the operating surgeon – which correlates with subjective reporting of stress. Some studies compared variables; one study suggested that laparoscopic colorectal surgery caused higher mental strain than open, while another suggested higher stress in surgeons while teaching compared to when primary operator. There have been no comparative trials using HRV in surgeons.

Conclusions

We present a review of the growing literature regarding HRV measurement in surgeons. This novel tool is a promising avenue to provide psychophysiological insight into the operating surgeon. This could guide future research into optimising the theatre environment for intra-operative performance using controlled or in-situ design.

Development and initial validation of the Cat HEalth and Wellbeing (CHEW) Questionnaire: a generic health-related quality of life instrument for cats

OBJECTIVES

The aims of the study were to define factors that owners consider relevant to the health-related quality of life (HRQoL) of cats, to develop an instrument based on this information, and to evaluate the validity and reliability of the final instrument (the Cat HEalth and Wellbeing [CHEW] Questionnaire).

METHODS

Psychometric research techniques and guidance from the US Food and Drug Administration on outcome measures were used to develop a valid and reliable instrument. Fifty-four cat owners and caregivers participated in the qualitative research, while 1303 cat owners were included in the quantitative validation phase (development dataset, n = 648; validation dataset, n = 655). A random subset of cat owners (n = 391) also participated in test-retest evaluation. Qualitative research was used to generate a draft instrument, which was then subjected to quantitative validation techniques. These included item reduction, domain identification, data quality assessment, and exploratory and confirmatory analysis to develop a final instrument, which underwent confirmatory reliability and validity assessment.

RESULTS

A draft instrument with 11 domains and 100 items based on qualitative research underwent online quantitative validation testing which refined the instrument to eight domains and 33 items. Confirmatory reliability and validity assessment showed that the final instrument had good validity, was able to discriminate between cats by age and overall health status, and demonstrated good internal and test-retest reliability.

CONCLUSIONS AND RELEVANCE

The CHEW Questionnaire was developed and validated. Additional research is needed to verify its ability to differentiate cats with and without disease, and to assess its potential as a screening tool.

Damage assessment in concrete structures using piezoelectric based sensors

Damage assessment in concrete structures using piezoelectric based sensorsABSTRACTPiezoelectric based PZT (Lead Zirconate Titanate) smart sensors offer significant potential for continuously monitoring the development and progression of internal damage in concrete structures. Changes in the resonant behavior in the measured electrical conductance obtained from electro-mechanical (EM) response of a PZT bonded to a concrete substrate is investigated for increasing levels of damage. Changes in the conductance resonant signature from EM conductance measurements are detected before visible signs of cracking. The root mean square deviation of the conductance signature at resonant peaks is shown to accurately reflect the level of damage in the substrate. The findings presented here provide a basis for developing a sensing methodology using PZT patches for continuous monitoring of concrete structures.Keywords: PZT; electro-mechanical impedance; conductance; microcracks.Evaluación de daños en estructuras de concreto utilizando sensores piezoeléctricosRESUMENLos sensores inteligentes PZT (Lead Zirconate Titanate) basados en piezoeléctricos ofrecen un potencial significativo para monitorear continuamente el desarrollo y la progresión de los daños internos en estructuras de concreto. Se investigan los cambios en el comportamiento resonante a través de la conductancia eléctrica medida, obtenida a partir de la respuesta electromecánica (EM) de un PZT unido a un sustrato de concreto para aumentar los niveles de daño. Los cambios en la resonancia de la conductancia EM se detectan antes de que aparezcan signos visibles de agrietamiento. La desviación cuadrática media de la raíz de la conductancia en los picos resonantes refleja con precisión el nivel de daño en el sustrato. Los hallazgos presentados aquí proporcionan una base para desarrollar una metodología de detección utilizando parches PZT para el monitoreo continuo de estructuras de concreto.Palabras clave: PZT; impedancia electromecánica; conductancia; microfisuras.Avaliação de danos em estruturas de concreto usando sensores piezoelétricos RESUMOOs sensores piezoelétricos inteligentes PZT (Lead Zirconate Titanate) oferecem um potencial significativo para o monitoramento contínuo do desenvolvimento e progressão de danos internos em estruturas de concreto. As alterações de ressonância através da medida da condutância elétrica obtida a partir da resposta eletromecânica (EM) de um PZT ligado a um substrato de concreto é investigada para níveis crescentes de danos. As alterações no perfil de ressonância de condutância EM são detectadas antes de sinais visíveis de fissuras. O desvio quadrático médio da raiz do perfil de condutância nos picos ressonantes é mostrado para refletir com precisão o nível de dano no substrato. Os resultados aqui apresentados fornecem uma base para o desenvolvimento de uma metodologia de detecção usando PZT para monitoramento contínuo de estruturas de concretoPalavras chave: PZT; impedância eletromecânica; condutância; microfissuras.

Oral supplementation of trans-cinnamaldehyde reduces uropathogenic Escherichia coli colonization in a mouse model

Urinary tract infections (UTIs) in the United States result in more than 7 million hospital visits per year. Uropathogenic Escherichia coli (UPEC) is responsible for more than 80% of UTIs. Although antibiotics are the drug of choice to control UTIs, their repeated use has resulted in the emergence of antibiotic-resistant UPEC. Thus, there is a need for effective alternate strategies to control UPEC infections. This study investigated the efficacy of trans-cinnamaldehyde (TC), a food-grade molecule present in cinnamon, in reducing UPEC colonization and pathogenesis in the lower UTI. Female C57BL/6 mice (6-8 weeks old) were fed ad libitum with 0, 0·1, 0·2 and 0·4% TC containing mouse chow for 10 days. Following TC supplementation, animals were experimentally infected with UPEC by transurethral catheterization. Mice were euthanized on days 1, 2 and 4 postinfection, and the bladder, urethra and urine were collected for bacterial enumeration. Prophylactic TC supplementation significantly (P ≤ 0·05) reduced UPEC colonization in the urinary bladder and urethra compared to the control. Results indicate that TC could potentially be used as an oral supplement to control UPEC-associated lower UTIs, however, follow-up clinical trials are warranted.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this study, we have demonstrated that oral supplementation of trans-cinnamaldehyde (TC) reduced uropathogenic Escherichia coli (UPEC)-associated lower urinary tract infection (UTI) in mice. Specifically, in-feed supplementation of TC significantly decreased UPEC populations in the urethra and bladder, thereby reducing the infectious load. These findings are particularly significant given the increase in incidence and prevalence of antibiotic-resistant UTIs. Our study offers new insights into the potential use of natural antimicrobials including TC, the active ingredient in cinnamon, as a nonantibiotic-based natural dietary intervention in the prophylaxis of lower UTIs.

Population Pharmacokinetics and Pharmacodynamics of the Calcimimetic Etelcalcetide in Chronic Kidney Disease and Secondary Hyperparathyroidism Receiving Hemodialysis

Etelcalcetide is a novel calcimimetic in development for the treatment of secondary hyperparathyroidism (SHPT). A population pharmacokinetic/pharmacodynamic (PK/PD) model was developed relating etelcalcetide exposures to markers of efficacy (parathyroid hormone [PTH]) and safety (calcium) using data from three clinical studies. The semimechanistic model was developed that included allosteric activation pharmacology and understanding of calcium homeostasis. The temporal profiles for all biomarkers were well described by the model. The cooperativity constant was 4.94, confirming allosteric activation mechanism. Subjects with more severe disease (higher PTH baseline) were predicted to experience less pronounced reduction in PTH (percentage change from baseline), but more reduction in calcium (Ca; percentage change from baseline). There was no evidence that dose adjustment by any covariate was needed. Model‐based simulations provided quantitative support to several elements of dosing, such as starting dose, monitoring, and titration timing for registration trials.

Inaccessible Masturbation, Impossible Mourning: Collective Melancholia, the Prohibition on Female Sexual Subjects in India, and Masturbation Fantasy as a Zone of the Strange

This paper explores a subjective experience-and identification-that a cohort of Indian women identifies as "home." This experience of "home" provides an attachment to a collective melancholia that keeps in place a prohibited female sexual subjectivity. The paper provides a brief historical overview of the prohibition of female sexual subjectivity and erotic agency in India. Following this, it discusses women's masturbation fantasies that illustrate the toggle between women's permitted and prohibited identifications. A clinical case example is presented to illustrate the hopelessness and mourning inherent in the psychoanalytic journey into subjectivity, a journey involving a departure from a shared cultural history.

Linear magnetoresistance caused by mobility fluctuations in n-doped Cd(3)As(2)

Cd(3)As(2) is a candidate three-dimensional Dirac semimetal which has exceedingly high mobility and nonsaturating linear magnetoresistance that may be relevant for future practical applications. We report magnetotransport and tunnel diode oscillation measurements on Cd(3)As(2), in magnetic fields up to 65 T and temperatures between 1.5 and 300 K. We find that the nonsaturating linear magnetoresistance persists up to 65 T and it is likely caused by disorder effects, as it scales with the high mobility rather than directly linked to Fermi surface changes even when approaching the quantum limit. From the observed quantum oscillations, we determine the bulk three-dimensional Fermi surface having signatures of Dirac behavior with a nontrivial Berry phase shift, very light effective quasiparticle masses, and clear deviations from the band-structure predictions. In very high fields we also detect signatures of large Zeeman spin splitting (g∼16).

Takotsubo cardiomyopathy following electroconvulsive therapy: an increasingly recognised phenomenon

Treatment of patients with severe depressive illnesses requiring electroconvulsive therapy (ECT) is challenging. This is compounded by the presence of physical comorbidities and potential complications. We report the case of a patient, on long-term bisoprolol, who developed acute epigastric pain and dyspnoea shortly after receiving ECT for treatment-refractory depression. An ECG showed new-onset ischaemic changes and a troponin-I level was elevated at 12 h. A diagnosis of Takotsubo cardiomyopathy was reached following angiography, which demonstrated left ventricular hypokinesia in the absence of coronary artery disease. With supportive treatment the patient made a good recovery. This report highlights the risk of developing Takotsubo cardiomyopathy following ECT despite β-adrenergic receptor blockade, and adds to a growing number of cases reporting this complication. Clinicians involved in the care of patients undergoing ECT must be aware of this complication and should consider Takotsubo cardiomyopathy in patients who develop atypical chest pain after ECT.

The Dental Practice Questionnaire: a patient feedback tool for improving the quality of dental practices

BACKGROUND

The recently introduced Practice Accreditation Scheme as part of the Australian National Safety and Quality Health Service (NSQHS) standards raises the question of how dental practices can implement valid and reliable patient experience feedback mechanisms for performance evaluation and enhancement. This article describes the development and use of a dental patient questionnaire (DPQ) that can be used for this purpose.

METHODS

DPQ was piloted on 58 voluntary dental practices across Australia and resulted in an average of just over 50 patient responses to 35 practices returned. Statistical properties of the DPQ were tested through validity (construct, content and criterion), structural integrity and reliability measurements.

RESULTS

DPQ is valid and reliable, with statistical analysis showing that there are significant differences in patients' scores depending on their age, gender, regularity of visit and number of years attending the practice. Two patient satisfaction models were derived. However, there may be scope for improving DPQ to more effectively produce patient feedback on summative aspects of services provided by dental practices.

CONCLUSIONS

DPQ has been shown to be 'fit for purpose' in its first pilot and may prove to be a useful tool for supporting dental practices in the Practice Accreditation Scheme.

The snoRNA domain of vertebrate telomerase RNA functions to localize the RNA within the nucleus

Telomerase RNA is an essential component of the ribonucleoprotein enzyme involved in telomere length maintenance, a process implicated in cellular senescence and cancer. Vertebrate telomerase RNAs contain a box H/ACA snoRNA motif that is not required for telomerase activity in vitro but is essential in vivo. Using the Xenopus oocyte system, we have found that the box H/ACA motif functions in the subcellular localization of telomerase RNA. We have characterized the transport and biogenesis of telomerase RNA by injecting labeled wild-type and variant RNAs into Xenopus oocytes and assaying nucleocytoplasmic distribution, intranuclear localization, modification, and protein binding. Although yeast telomerase RNA shares characteristics of spliceosomal snRNAs, we show that human telomerase RNA is not associated with Sm proteins or efficiently imported into the nucleus. In contrast, the transport properties of vertebrate telomerase RNA resemble those of snoRNAs; telomerase RNA is retained in the nucleus and targeted to nucleoli. Furthermore, both nuclear retention and nucleolar localization depend on the box H/ACA motif. Our findings suggest that the H/ACA motif confers functional localization of vertebrate telomerase RNAs to the nucleus, the compartment where telomeres are synthesized. We have also found that telomerase RNA localizes to Cajal bodies, intranuclear structures where it is thought that assembly of various cellular RNPs takes place. Our results identify the Cajal body as a potential site of telomerase RNP biogenesis.

Beneficial effects of garlic (Allium sativum Linn) on rats fed with diets containing cholesterol and either of the oil seeds, coconuts or groundnuts

Feeding of 2% cholesterol diet increased lipid parameters in serum and tissues of rats during a period of one month. In addition to the above, lipid peroxidation also increased and activities of certain enzymes were significantly altered in the tissues. Similar changes were also observed to a greater extent with diets containing 40% by weight of coconut kernel or groundnut with and without 2% cholesterol. The enzymes studied were HMGCoA reductase, AST, ALT and ALP in tissues and serum as the case may be. In general the atherogenic effects were observed more with groundnut containing diets than those with coconut. Even though the oil from the former is mostly unsaturated and that from the latter is mostly saturated, these analytical criteria do not relate to their atherogenic effects. When 5% garlic was incorporated with any of the high fat diets, the lipid parameters, their peroxidation and alterations in enzyme activities were significantly decreased. These results show that garlic contains some principles that counteract the atherogenicity of the above oil seeds.

Internal modification of U2 small nuclear (sn)RNA occurs in nucleoli of Xenopus oocytes

U2 small nuclear (sn)RNA contains a large number of posttranscriptionally modified nucleotides, including a 5' trimethylated guanosine cap, 13 pseudouridines, and 10 2'-O-methylated residues. Using Xenopus oocytes, we demonstrated previously that at least some of these modified nucleotides are essential for biogenesis of a functional snRNP. Here we address the subcellular site of U2 internal modification. Upon injection into the cytoplasm of oocytes, G-capped U2 that is transported to the nucleus becomes modified, whereas A-capped U2 that remains in the cytoplasm is not modified. Furthermore, by injecting U2 RNA into isolated nuclei or enucleated oocytes, we observe that U2 internal modifications occur exclusively in the nucleus. Analysis of the intranuclear localization of fluorescently labeled RNAs shows that injected wild-type U2 becomes localized to nucleoli and Cajal bodies. Both internal modification and nucleolar localization of U2 are dependent on the Sm binding site. An Sm-mutant U2 is targeted only to Cajal bodies. The Sm binding site can be replaced by a nucleolar localization signal derived from small nucleolar RNAs (the box C/D motif), resulting in rescue of internal modification as well as nucleolar localization. Analysis of additional chimeric U2 RNAs reveals a correlation between internal modification and nucleolar localization. Together, our results suggest that U2 internal modification occurs within the nucleolus.

Failure of presynaptic purinoceptors to modulate noradrenaline release from sympathetic nerves in human dental pulp

The effects of putative presynaptic P1- and/or P2-purinoceptors on the release of noradrenaline from sympathetic nerves in human dental pulp were examined by testing the effects of agonists and an antagonist of these receptors on the stimulation-induced overflow of [(3)H]noradrenaline from tissue treated with desipramine (0.3 micromol/l) and preincubated with [(3)H]noradrenaline (0.6 micromol/l). The P1-purinoceptor agonists adenosine (1.0 mmol/l) and 2-chloroadenosine (0.01-1.0 mmol/l) and the antagonist 8-cyclopentyl-1,3-dipropyl xanthine (1.0 micromol/l), and the P2-purinoceptor agonists ATP (0.1 mmol/l) and beta, gamma-methylene-ATP (0.01 mmol/l), did not modulate the release of noradrenaline. Adenosine was also without effect in dental pulp treated with the alpha(2)-adrenoceptor antagonist rauwolscine. It is concluded that presynaptic P1-purinoceptors and those P2-purinoceptors activated by adenine nucleotides are either not present on sympathetic nerves in human dental pulp or that they exert little or no effect on the release of noradrenaline.

Nuclear retention elements of U3 small nucleolar RNA

The processing and methylation of precursor rRNA is mediated by the box C/D small nucleolar RNAs (snoRNAs). These snoRNAs differ from most cellular RNAs in that they are not exported to the cytoplasm. Instead, these RNAs are actively retained in the nucleus where they assemble with proteins into mature small nucleolar ribonucleoprotein particles and are targeted to their intranuclear site of action, the nucleolus. In this study, we have identified the cis-acting sequences responsible for the nuclear retention of U3 box C/D snoRNA by analyzing the nucleocytoplasmic distributions of an extensive panel of U3 RNA variants after injection of the RNAs into Xenopus oocyte nuclei. Our data indicate the importance of two conserved sequence motifs in retaining U3 RNA in the nucleus. The first motif is comprised of the conserved box C' and box D sequences that characterize the box C/D family. The second motif contains conserved box sequences B and C. Either motif is sufficient for nuclear retention, but disruption of both motifs leads to mislocalization of the RNAs to the cytoplasm. Variant RNAs that are not retained also lack 5' cap hypermethylation and fail to associate with fibrillarin. Furthermore, our results indicate that nuclear retention of U3 RNA does not simply reflect its nucleolar localization. A fragment of U3 containing the box B/C motif is not localized to nucleoli but retained in coiled bodies. Thus, nuclear retention and nucleolar localization are distinct processes with differing sequence requirements.

Nucleolar localization signals of box H/ACA small nucleolar RNAs

The two major families of small nucleolar RNAs (snoRNAs), Box C/D and Box H/ACA, are generated in the nucleoplasm and transported to the nucleolus where they function in rRNA processing and modification. We have investigated the sequences involved in the intranuclear transport of Box H/ACA snoRNAs by assaying the localization of injected fluorescent RNAs in Xenopus oocyte nuclear spreads. Our analysis of U17, U64 and U65 has revealed that disruption of either of the conserved sequence elements, Box H or Box ACA, eliminates nucleolar localization. In addition, the stem present at the base of the 3' hairpin is required for efficient nucleolar localization of U65. Fragments or rearrangements of U65 that consist of Box H and Box ACA flanking either the 5' or 3' hairpin are targeted to the nucleolus. The targeting is dependent on the presence of the Box sequences, but not on their orientation. Our results indicate that in each of the two major families of snoRNAs, a motif composed of the signature conserved sequences and an adjacent structural element that tethers the sequence elements directs the nucleolar localization of the RNAs. We demonstrate that telomerase RNA is also targeted to the nucleolus by a Box ACA-dependent mechanism.

Role of the box C/D motif in localization of small nucleolar RNAs to coiled bodies and nucleoli

Small nucleolar RNAs (snoRNAs) are a large family of eukaryotic RNAs that function within the nucleolus in the biogenesis of ribosomes. One major class of snoRNAs is the box C/D snoRNAs named for their conserved box C and box D sequence elements. We have investigated the involvement of cis-acting sequences and intranuclear structures in the localization of box C/D snoRNAs to the nucleolus by assaying the intranuclear distribution of fluorescently labeled U3, U8, and U14 snoRNAs injected into Xenopus oocyte nuclei. Analysis of an extensive panel of U3 RNA variants showed that the box C/D motif, comprised of box C', box D, and the 3' terminal stem of U3, is necessary and sufficient for the nucleolar localization of U3 snoRNA. Disruption of the elements of the box C/D motif of U8 and U14 snoRNAs also prevented nucleolar localization, indicating that all box C/D snoRNAs use a common nucleolar-targeting mechanism. Finally, we found that wild-type box C/D snoRNAs transiently associate with coiled bodies before they localize to nucleoli and that variant RNAs that lack an intact box C/D motif are detained within coiled bodies. These results suggest that coiled bodies play a role in the biogenesis and/or intranuclear transport of box C/D snoRNAs.

Early results from indirect drug susceptibility test for tubercle bacilli

The indirect susceptibility test results on L-J medium for tubercle bacilli against streptomycin, isoniazid and rifampicin were read at the end of 2 wk and compared with the results at 4 wk. It was found that drug resistance could be correctly predicted in over 70 per cent of cultures including multi-drug resistant tuberculosis (MDR TB) strains at the end of 2 wk. The susceptibility to para-nitrobenzoic acid (PNB) read at 2 wk was able to distinguish non-tuberculous mycobacteria from Mycobacterium tuberculosis cultures. The early detection of resistance by this procedure requires only minimum inputs, and can benefit the majority of patients harbouring drug resistant tubercle bacilli.