Corneal pannus, Herbert's pits and conjunctival inflammation in older children in Papua New Guinea

PURPOSE

The prevalence of trachomatous inflammation-follicular (TF) in Papua New Guinea (PNG) suggests antibiotic mass drug administration (MDA) is needed to eliminate trachoma as a public health problem but the burden of trichiasis is low. As a result, WHO issued bespoke recommendations for the region. If ≥ 20% of 10-14-year-olds have both any conjunctival scarring (C1 or C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued. Equally, if ≥ 5% of that group have both moderate/severe conjunctival scarring (C2 or C3) and corneal pannus and/or Herbert's pits, MDA should be continued.

METHODS

We identified 14 villages where > 20% of 1-9-year-olds had TF during baseline mapping undertaken 4 years and 1 month previously. Every child aged 10-14 years in those villages was eligible to be examined for clinical signs of corneal pannus, Herbert's pits and conjunctival scarring. A grading system that built on existing WHO grading systems was used.

RESULTS

Of 1,293 resident children, 1,181 (91%) were examined. Of 1,178 with complete examination data, only one (0.08%) individual had concurrent scarring and limbal signs.

CONCLUSIONS

The WHO-predefined criteria for continuation of MDA were not met. Ongoing behavioural and environmental improvement aspects of the SAFE strategy may contribute to integrated NTD control. Surveillance methods should be strengthened to enable PNG health authorities to identify future changes in disease prevalence.

Gender differences in the surgical management of trachomatous trichiasis: an exploratory analysis of global trachoma survey data, 2015-2019

BACKGROUND

Trachomatous trichiasis (TT) is a painful, potentially blinding eye condition that can be managed through epilation or surgery. Women are affected by TT approximately twice as often as men and are believed to face gendered barriers to receiving surgical care to prevent vision loss.

METHODS

We used data from 817 cross-sectional surveys conducted during 2015-2019 in 20 African countries to estimate the prevalence difference (PD) between female and male eyes for four outcomes potentially indicating gender-related differences in TT management: (1) received surgery and developed postoperative TT (PTT), (2) never offered surgery, (3) offered surgery but declined it, and (4) offered epilation but never offered surgery.

RESULTS

The prevalence was modestly elevated among female eyes compared with male eyes for having PTT (PD:1.8 [95% confidence limits (CL): 0.6, 3.0]) and having declined surgery for the eye (PD: 6.2 [95% CL: 1.8, 10.7]). The proportion offered epilation was similar by gender (PD:0.5 [95% CL: -0.4, 1.3]), while never having been offered surgery was somewhat more prevalent among male eyes (PD: -2.1 [95% CL: -3.5, -0.7]).

CONCLUSIONS

Our results suggest potential gender differences in TT management. More research is needed to determine the causes and implications of the observed differences.

Tropical Data: Approach and Methodology as Applied to Trachoma Prevalence Surveys

PURPOSE

Population-based prevalence surveys are essential for decision-making on interventions to achieve trachoma elimination as a public health problem. This paper outlines the methodologies of Tropical Data, which supports work to undertake those surveys.

METHODS

Tropical Data is a consortium of partners that supports health ministries worldwide to conduct globally standardised prevalence surveys that conform to World Health Organization recommendations. Founding principles are health ministry ownership, partnership and collaboration, and quality assurance and quality control at every step of the survey process. Support covers survey planning, survey design, training, electronic data collection and fieldwork, and data management, analysis and dissemination. Methods are adapted to meet local context and needs. Customisations, operational research and integration of other diseases into routine trachoma surveys have also been supported.

RESULTS

Between 29th February 2016 and 24th April 2023, 3373 trachoma surveys across 50 countries have been supported, resulting in 10,818,502 people being examined for trachoma.

CONCLUSION

This health ministry-led, standardised approach, with support from the start to the end of the survey process, has helped all trachoma elimination stakeholders to know where interventions are needed, where interventions can be stopped, and when elimination as a public health problem has been achieved. Flexibility to meet specific country contexts, adaptation to changes in global guidance and adjustments in response to user feedback have facilitated innovation in evidence-based methodologies, and supported health ministries to strive for global disease control targets.

Trachoma, Anti-Pgp3 Serology, and Ocular Chlamydia trachomatis Infection in Papua New Guinea

BACKGROUND

In Melanesia, the prevalence of trachomatous inflammation-follicular (TF) suggests that public health-level interventions against active trachoma are needed. However, the prevalence of trachomatous trichiasis is below the threshold for elimination as a public health problem and evidence of conjunctival infection with trachoma's causative organism (Chlamydia trachomatis [CT]) is rare. Here, we examine the prevalence of ocular infection with CT and previous exposure to CT in three evaluation units (EUs) of Papua New Guinea.

METHODS

All individuals aged 1-9 years who were examined for clinical signs of trachoma in 3 Global Trachoma Mapping Project EUs were eligible to take part in this study (N = 3181). Conjunctival swabs were collected from 349 children with TF and tested by polymerase chain reaction to assess for ocular CT infection. Dried blood spots were collected from 2572 children and tested for anti-Pgp3 antibodies using a multiplex assay.

RESULTS

The proportion of children with TF who had CT infection was low across all 3 EUs (overall 2%). Anti-Pgp3 seroprevalence was 5.2% overall and there was no association between anti-Pgp3 antibody level and presence of TF. In 2 EUs, age-specific seroprevalence did not increase significantly with increasing age in the 1- to 9-year-old population. In the third EU, there was a statistically significant change with age but the overall seroprevalence and peak age-specific seroprevalence was very low.

CONCLUSIONS

Based on these results, together with similar findings from the Solomon Islands and Vanuatu, the use of TF to guide antibiotic mass drug administration decisions in Melanesia should be reviewed.

Short-Term Low-Dose Propofol Anaesthesia Associated with Severe Metabolic Acidosis

Propofol-induced metabolic acidosis is well recognised in the paediatric literature, but the existence of such a syndrome in adults remains contentious. In most reported cases, metabolic acidosis complicated prolonged administration of propofol in critically ill patients. We present a case of severe non-fatal reversible metabolic acidosis, without ventilatory depression or hypoxia, related to short-term propofol infusion in an adult during and after coronary artery bypass grafting. We suggest that lactic acidosis occurred in a genetically susceptible patient with an abnormality of mitochondrial function. This report discusses an unusual adverse effect of propofol anaesthesia and sedation and highlights the need for further investigation to define propofol toxicity.

Population-Based Trachoma Mapping in Six Evaluation Units of Papua New Guinea

PURPOSE

We sought to determine the prevalence of trachomatous inflammation - follicular (TF) in children aged 1-9 years, and trachomatous trichiasis (TT) in those aged ≥15 years, in suspected trachoma-endemic areas of Papua New Guinea (PNG).

METHODS

We carried out six population-based prevalence surveys using the protocol developed as part of the Global Trachoma Mapping Project.

RESULTS

A total of 19,013 individuals were sampled for inclusion, with 15,641 (82.3%) consenting to participate. Four evaluation units had prevalences of TF in children ≥10%, above which threshold the World Health Organization (WHO) recommends mass drug administration (MDA) of azithromycin for at least three years; Western Province (South Fly/Daru) 11.2% (95% confidence interval, CI, 6.9-17.0%), Southern Highlands (East) 12.2% (95% CI 9.6-15.0%), Southern Highlands (West) 11.7% (95% CI 8.5-15.3%), and West New Britain 11.4% (95% CI 8.7-13.9%). TF prevalence was 5.0-9.9% in Madang (9.4%, 95% CI 6.1-13.0%) and National Capital District (6.0%. 95% CI 3.2-9.1%) where consideration of a single round of MDA is warranted. Cases of TT were not found outside West New Britain, in which four cases were seen, generating an estimated population-level prevalence of TT in adults of 0.10% (95% CI 0.00-0.40%) for West New Britain, below the WHO elimination threshold of 0.2% of those aged ≥15 years.

CONCLUSION

Trachoma is a public health issue in PNG. However, other than in West New Britain, there are few data to support the idea that trachoma is a cause of blindness in PNG. Further research is needed to understand the stimulus for the active trachoma phenotype in these populations.

A Japanese-specific recurrent mutation and a novel splice site mutation in the LAMC2 gene identified in two Japanese families with Herlitz junctional epidermolysis bullosa

BACKGROUND

Herlitz junctional epidermolysis bullosa (H-JEB) is an extremely rare genodermatosis characterized by lethality owing to severe blister formation. We report two unrelated Japanese patients with H-JEB. Genetic analyses detected a single nonsense mutation on the LAMC2 gene in these two patients.

AIM

To identify the mutation involved and describe the first reported Japanese recurrent mutation in the LAMC2 gene.

METHODS

Direct sequencing was performed of DNA from either peripheral blood or fetal cells in amniotic fluid. Reverse transcriptase PCR was used to confirm that an aberrant transcript resulted from the splice site mutation. A haplotype analysis was performed to define the origin of the recurrent mutation.

RESULTS

Both patients had blisters and erosions on the trunk and limbs at birth, with nail dystrophy. Patient 1 died as a result of sepsis at 30 weeks of age, and patient 2 died as a result of disseminated intravascular coagulation at 20 weeks of age. Mutation analysis of the LAMC2 gene revealed that patient 1 was compound heterozygous for a nonsense mutation (p.Cys553X) and a novel splice site mutation (c.2868+1delG), and patient 2 was a homozygous for p.Cys553X. Prenatal diagnosis performed during a subsequent pregnancy in family 2 revealed that this second child was heterozygous for p.Cys553X, and was thus not affected. Haplotype analysis suggested that a p.Cys553X allele derived from the same origin had been independently inherited by these two unrelated families.

CONCLUSIONS

p.Cys553X in the LAMC2 gene may be a Japanese-specific recurrent mutation as a result of a founder effect, and it may therefore be useful for initial screening in the mutation analysis of H-JEB.

The current status of percutaneous nephrolithotomy in the management of kidney stones

Large kidney stones (>2 cm) is a common problem affecting all population groups across the globe and may result in significant complications if left untreated. The treatment for this condition has evolved dramatically over the past seven decades with the advent of minimally invasive treatment options. At the forefront of this paradigm shift is the development of percutaneous nephrolithotomy (PCNL). This has resulted in shorter hospital stays, reduced postoperative pain, and quicker convalescence compared with the previous criterion standard of open stone surgery. PCNL is only one of the many minimally invasive treatment options available for this condition, but remains the most efficient in all patient groups. However, it continues to be one of the more challenging urological procedures, which if not performed well, can be associated with significant complications. Refinements in techniques, improvement in equipment and increasing clinical experience have led to improved stone free rates being achieved with acceptably low patient morbidity. In this article, authors review the technical aspects, outcomes, and current role of PCNL in the treatment of large kidney stones.

Surgical treatment of simple syndactylism with secondary deep digital flexor tendon contracture in a Basset Hound

A five-month-old, female Basset Hound was presented for lameness associated with a fused 3rd and 4th digital pad on the left hind limb (simple incomplete syndactyly), and secondary contracture of the deep digital flexure tendon of the 3rd and 4th digit. An onychectomy of the third phalanx of the third and fourth digits was performed. Following the operation, the dog gained good use of the affected limb for one month until intermittent non-weight bearing lameness developed. A second surgery was performed six months later, partially removing the second phalanx of digits three and four. Follow-up reports indicate that the dog is doing well and is without lameness. This is the first report of deep digital flexor tendon contracture and surgical treatment of this complication in canine simple syndactylism.

Identification and characterization of two distinct GnRH receptor subtypes in a teleost, the medaka Oryzias latipes

We report the identification and characterization of two distinct GnRH receptor (GnRH-R) subtypes, designated GnRH-R1 and GnRH-R2, in a model teleost, the medaka Oryzias latipes. These seven-transmembrane receptors of the medaka contain a cytoplasmic C-terminal tail, which has been found in all other nonmammalian GnRH-Rs cloned to date. The GnRH-R1 gene is composed of three exons separated by two introns, whereas the GnRH-R2 gene has an additional intron and therefore consists of four exons and three introns. The GnRH-R1 and GnRH-R2 genes, both of which exist as single-copy genes in the medaka genome, were mapped to linkage groups 3 and 16, respectively. Inositol phosphate assays using COS-7 cells transfected with GnRH-R1 and GnRH-R2 demonstrated that they had remarkably different ligand sensitivities, although both receptors showed highest preference for chicken-II-type GnRH. Phylogenetic analysis showed the presence of three paralogous lineages for vertebrate GnRH-Rs and indicated that neither GnRH-R1 nor GnRH-R2 is the medaka ortholog to mammalian GnRH-Rs that lack a cytoplasmic tail. This, together with an observation that medaka-type GnRH had low affinity for GnRH-R1 and GnRH-R2, suggests that a third GnRH-R may exist in the medaka.

Structural and functional analysis of the Xestia c-nigrum granulovirus matrix metalloproteinase

Sequence analysis of the Xestia c-nigrum granulovirus (XcGV) genome identified an open reading frame encoding a 469-amino-acid (54-kDa) protein with over 30% amino acid sequence identity to a region of about 150 amino acids that includes the catalytic domains of human stromelysin 1 (Str1)/matrix metalloproteinase 3 (MMP-3) (EC 3.4.24.17) and sea urchin hatching enzyme (HE). Stromelysin homologs have not been reported from baculoviruses or other viruses. Unlike human Str1 and sea urchin HE, the putative XcGV-MMP does not have a signal peptide and lacks the peptide motif involved in the cysteine switch that maintains other MMPs in an inactive form. The putative XcGV-MMP, however, possesses a conserved zinc-binding motif in its putative catalytic domain. The XcGV-MMP homolog was cloned, and a recombinant Bombyx mori nucleopolyhedrovirus (BmNPV) that expresses XcGV-MMP under the polyhedrin promoter was constructed. A distinct pattern of melanization was observed in B. mori larvae infected with MMP-expressing BmNPV. Fat body extracts from larvae overexpressing the 54-kDa recombinant MMP digested dye-impregnated collagen (Azocoll). The enzymatic activity was inhibited by two metalloproteinase inhibitors, EDTA and 1,10-phenanthroline. These results suggest that the XcGV MMP-3 gene homolog encodes a functional metalloproteinase.

Sequence analysis of the Xestia c-nigrum granulovirus genome

The nucleotide sequence of the Xestia c-nigrum granulovirus (XcGV) genome was determined and found to comprise 178,733 bases with a G+C content of 40.7%. It contained 181 putative genes of 150 nucleotides or greater that showed minimal overlap. Eighty-four of these putative genes, which collectively accounted for 43% of the genome, are homologs of genes previously identified in the Autographa californica multinucleocapsid nucleopolyhedrovirus (AcMNPV) genome. These homologs showed on average 33% amino acid sequence identity to those from AcMNPV. Several genes reported to have major roles in AcMNPV biology including ie-2, gp64, and egt were not found in the XcGV genome. However, open reading frames with homology to DNA ligase, two DNA helicases (one similar to a yeast mitochondrial helicase and the other to a putative AcMNPV helicase), and four enhancins (virus enhancing factors) were found. In addition, several ORFs are repeated; there are 7 genes related to AcMNPV orf2, 4 genes related to AcMNPV orf145/150, and a number of repeated genes unique to XcGV. Eight major repeated sequences (XcGV hrs) that are similar to sequences found in the Trichoplusia ni GV genome (TnGV) were found.

Identification of an ATP-driven, osmoregulated glycine betaine transport system in Listeria monocytogenes

The ability of the gram-positive, food-borne pathogen Listeria monocytogenes to tolerate environments of elevated osmolarity and reduced temperature is due in part to the transport and accumulation of the osmolyte glycine betaine. Previously we showed that glycine betaine transport was the result of Na(+)-glycine betaine symport. In this report, we identify a second glycine betaine transporter from L. monocytogenes which is osmotically activated but does not require a high concentration of Na(+) for activity. By using a pool of Tn917-LTV3 mutants, a salt- and chill-sensitive mutant which was also found to be impaired in its ability to transport glycine betaine was isolated. DNA sequence analysis of the region flanking the site of transposon insertion revealed three open reading frames homologous to opuA from Bacillus subtilis and proU from Escherichia coli, both of which encode glycine betaine transport systems that belong to the superfamily of ATP-dependent transporters. The three open reading frames are closely spaced, suggesting that they are arranged in an operon. Moreover, a region upstream from the first reading frame was found to be homologous to the promoter regions of both opuA and proU. One unusual feature not shared with these other two systems is that the start codons for two of the open reading frames in L. monocytogenes appear to be TTG. That glycine betaine uptake is nearly eliminated in the mutant strain when it is assayed in the absence of Na(+) is an indication that only the ATP-dependent transporter and the Na(+)-glycine betaine symporter occur in L. monocytogenes.

Adverse reactions to watch for in patients using herbal remedies

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Polyhedron-like inclusion body formation by a mutant nucleopolyhedrovirus expressing the granulin gene from a granulovirus

The polyhedrin gene in Bombyx mori nucleopolyhedrovirus (BmNPV) was replaced with the granulin gene of Trichoplusia ni granulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infected B. mori and BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability.

Glycine betaine confers enhanced osmotolerance and cryotolerance on Listeria monocytogenes

Listeria monocytogenes is a gram-positive food-borne pathogen that is notably resistant to osmotic stress and can grow at refrigerator temperatures. These two characteristics make it an insidious threat to public health. Like several other organisms, L. monocytogenes accumulates glycine betaine, a ubiquitous and effective osmolyte, intracellularly when grown under osmotic stress. However, it also accumulates glycine betaine when grown under chill stress at refrigerator temperatures. Exogenously added glycine betaine enhances the growth rate of stressed but not unstressed cells, i.e., it confers both osmotolerance and cryotolerance. Both salt-stimulated and cold-stimulated accumulation of glycine betaine occur by transport from the medium rather than by biosynthesis. Direct measurement of glycine betaine uptake shows that cells transport betaine 200-fold faster at high salt concentration (4% NaCl) than without added salt and 15-fold faster at 7 than at 30 degrees C. The kinetics of glycine betaine transport suggest that the two transport systems are indistinguishable in terms of affinity for betaine and may be the same. Hyperosmotic shock and cold shock experiments suggest the transport system(s) to be constitutive; activation was not blocked by chloramphenicol. A cold-activated transport system is a novel observation and has intriguing implications concerning the physical state of the cell membrane at low temperature.

Microbial reduction of 1-(4-fluorophenyl)-4-[4-(5-fluoro-2-pyrimidinyl)-1- piperazinyl]butan-1-one

Among various micro-organisms screened for the stereoselective reduction of 4-chloro-1-(4-fluorophenyl)butan-1-one (1), Hansenula polymorpha [American Type Culture Collection (A.T.C.C.) 26012 and 86014], Nocardia salmonicolor [Squibb Culture (S.C.) 6370], Arthobacter simplex (A.T.C.C. 6949), Mycobacterium vaccae (A.T.C.C. 29678), Candida boidinii (A.T.C.C. 13821) and Saccharomyces cerevisiae (A.T.C.C. 13792) reduced compound 1 to the corresponding (R)-(+)-alcohol (2). In contrast, Lactobacillus kefir (A.T.C.C. 35411), Pullularia pullulans (A.T.C.C. 16623), Trigonopsis variabilis (A.T.C.C. 10679) and Cunninghamella echinulata (A.T.C.C. 26269) reduced compound 1 to the (S)-(-)-alcohol (2). When 1-(4-fluorophenyl)-4-(1-piperazinyl)butan-1-one (3) was used as substrate for the reduction, only Nocardia globerula (A.T.C.C. 12505) and Saccharomyces cerevisiae (A.T.C.C. 13792) converted compound 3 into the corresponding (R)-(+)-alcohol (4). Organisms which reduced compound 1 were inactive for the reduction of compound 3. 1-(4-Fluorophenyl)-4-[4-(5-fluoro-2- pyrimidinyl)butan-1-one (5) was reduced to the corresponding (R)-(+)-alcohol (6) by Mortierella ramanniana (A.T.C.C. 38191) and to the (S)-(-)-alcohol (6) by Pullularia pullulans (A.T.C.C. 16623). (R)-(+)-compound 2 and compound 4 are key chiral intermediates in the total chemical synthesis of (R)-(+)-compound 6, an effective antipsychotic agent under development at Bristol-Myers Squibb. A single-stage (fermentation/biotransformation) process and two-stage (fermentation and subsequent biotransformation by cell suspensions) process were developed for the stereoselective reduction of compound 5 to (R)-(+)-compound 6 by Mortierella ramanniana (A.T.C.C. 38191). In both processes, the reaction yield of 98% and the optical purity of 99.4% were obtained for (R)-(+)-compound 6. The enzyme which catalysed the reduction of compound 5 to (R)-(+)-compound 6 was purified to homogeneity. The purified protein consisted of a single polypeptide of 29 kDa.

Acetaminophen does not impair clearance of zidovudine

OBJECTIVE

To determine whether concurrent treatment with acetaminophen and zidovudine impairs clearance of zidovudine, thereby increasing the risk for zidovudine-induced hematologic toxicity.

DESIGN

Dose escalation, drug interaction study.

SETTING

University clinical research center.

PATIENTS

Patients with the acquired immunodeficiency syndrome (AIDS) or advanced AIDS-related complex.

INTERVENTIONS

Acetaminophen and 200 mg of zidovudine simultaneously every 4 hours. For 13 patients, the unit dosage of acetaminophen was 325 mg for 3 days; for 8 patients, the dosage was 650 mg for 3 days; and, for 6 patients, the dosage was 650 mg for 7 days.

MEASUREMENTS

Zidovudine clearance and production of the glucuronide conjugate of zidovudine were assessed after acetaminophen treatment.

MAIN RESULTS

Neither zidovudine clearance nor production of the glucuronide conjugate of zidovudine was impaired after treatment with acetaminophen. Clearance of zidovudine was actually accelerated by 5%, 11%, and 33% with the three acetaminophen regimens, respectively (P = 0.002 by analysis of variance; P = 0.04 for linear trend when changes in the area-under-the-curve for zidovudine were compared).

CONCLUSION

Because serum concentrations of zidovudine decrease after the coadministration of acetaminophen, a pharmacokinetic interaction between zidovudine and acetaminophen is unlikely to increase the risk for hematologic toxicity associated with zidovudine.

Phase I toxicity and pharmacology study of trimethylcolchicinic acid in patients with advanced malignancies

A phase I study of trimethylcolchicinic acid (TMCA) given orally once daily for 5 days every 3rd week was performed in 19 patients with advanced malignancies. Myelosuppression and mucositis were the major toxicities observed. Serum TMCA levels were monitored and appear to be useful in predicting toxicities. A partial response was seen in one lymphoma patient and stabilization of disease was noted in one patient each with prostatic and ovarian cancer.