Spatial-temporal and phylogenetic analyses of epidemiologic data to help understand the modes of transmission of endemic typhoid fever in Samoa.

Salmonella enterica serovar Typhi (S. Typhi) is either widely distributed or proximally transmitted via fecally-contaminated food or water to cause typhoid fever. In Samoa, where endemic typhoid fever has persisted over decades despite water quality and sanitation improvements, the local patterns of S. Typhi circulation remain unclear. From April 2018-June 2020, epidemiologic data and GPS coordinates were collected during household investigations of 260 acute cases of typhoid fever, and 27 asymptomatic shedders of S. Typhi were detected among household contacts. Spatial and temporal distributions of cases were examined using Average Nearest Neighbor and space-time hotspot analyses. In rural regions, infections occurred in sporadic, focal clusters contrasting with persistent, less clustered cases in the Apia Urban Area. Restrictions to population movement during nationwide lockdowns in 2019-2020 were associated with marked reductions of cases. Phylogenetic analyses of isolates with whole genome sequences (n = 186) revealed one dominant genotype 3.5.4 (n = 181/186) that contains three Samoa-exclusive sub-lineages: 3.5.4.1, 3.5.4.2, and 3.5.4.3. Variables of patient sex, age, and geographic region were examined by phylogenetic groupings, and significant differences (p<0.05) associated genetically-similar isolates in urban areas with working ages (20-49 year olds), and in rural areas with age groups typically at home (<5, 50+). Isolates from asymptomatic shedders were among all three sub-lineages. Whole genome sequencing provided evidence of bacterial genetic similarity, which corroborated 10/12 putative epidemiologic linkages among cases and asymptomatic shedders, as well as 3/3 repeat positives (presumed relapses), with a median of one single nucleotide polymorphism difference. These findings highlight various patterns of typhoid transmission in Samoa that differ between urban and rural regions as well as genomic subtypes. Asymptomatic shedders, detectable only through household investigations, are likely an important reservoir and mobile agent of infection. This study advances a "Samoan S. Typhi framework" that supports current and future typhoid surveillance and control efforts in Samoa.

Persistence of Rare Salmonella Typhi Genotypes Susceptible to First-Line Antibiotics in the Remote Islands of Samoa.

For decades, the remote island nation of Samoa (population ~200,000) has faced endemic typhoid fever despite improvements in water quality, sanitation, and economic development. We recently described the epidemiology of typhoid fever in Samoa from 2008 to 2019 by person, place, and time; however, the local Salmonella enterica serovar Typhi (S. Typhi) population structure, evolutionary origins, and genomic features remained unknown. Herein, we report whole genome sequence analyses of 306 S. Typhi isolates from Samoa collected between 1983 and 2020. Phylogenetics revealed a dominant population of rare genotypes 3.5.4 and 3.5.3, together comprising 292/306 (95.4%) of Samoan versus 2/4934 (0.04%) global S. Typhi isolates. Three distinct 3.5.4 genomic sublineages were identified, and their defining polymorphisms were determined. These dominant Samoan genotypes, which likely emerged in the 1970s, share ancestry with other 3.5 clade isolates from South America, Southeast Asia, and Oceania. Additionally, a 106-kb pHCM2 phenotypically cryptic plasmid, detected in a 1992 Samoan S. Typhi isolate, was identified in 106/306 (34.6%) of Samoan isolates; this is more than double the observed proportion of pHCM2-containing isolates in the global collection. In stark contrast with global S. Typhi trends, resistance-conferring polymorphisms were detected in only 15/306 (4.9%) of Samoan S. Typhi, indicating overwhelming susceptibility to antibiotics that are no longer effective in most of South and Southeast Asia. This country-level genomic framework can help local health authorities in their ongoing typhoid surveillance and control efforts, as well as fill a critical knowledge gap in S. Typhi genomic data from Oceania. IMPORTANCE In this study, we used whole genome sequencing and comparative genomics analyses to characterize the population structure, evolutionary origins, and genomic features of S. Typhi associated with decades of endemic typhoid fever in Samoa. Our analyses of Samoan isolates from 1983 to 2020 identified a rare S. Typhi population in Samoa that likely emerged around the early 1970s and evolved into sublineages that are presently dominant. The dominance of these endemic genotypes in Samoa is not readily explained by genomic content or widespread acquisition of antimicrobial resistance. These data establish the necessary framework for future genomic surveillance of S. Typhi in Samoa for public health benefit.

Point-of-Care Ultrasound by Nonexpert Operators Demonstrates High Sensitivity and Specificity in Detecting Gallstones: Data from the Samoa Typhoid Fever Control Program.

Approximately 90% of chronic typhoid carriers with persistent Salmonella enterica serovar Typhi (S. Typhi) gallbladder infection have gallstones. In Samoa, where typhoid fever has been endemic for many decades, risk factors predisposing to the development of gallstones are increasing among adults. The Samoa Typhoid Fever Control Program dispatches a "Typhoid Epidemiologic SWAT Team" to perform a household investigation of every blood culture-confirmed case of acute typhoid fever. Investigations include screening household contacts to detect chronic carriers. Following limited training, two nonexpert ultrasound operators performed point-of-care ultrasound (POCUS) on 120 Samoan adults from August to September 2019 to explore the feasibility of POCUS to detect individuals with gallstones during household investigations and community screenings. POCUS scans from 120 Samoan adults in three cohorts (28 food handlers, two typhoid cases and their 18 household contacts, and 72 attendees at an ambulatory clinic) were reviewed by a board-certified radiologist who deemed 96/120 scans (80%) to be interpretable. Compared with the radiologist (gold standard), the nonexpert operators successfully detected 6/7 Samoans with gallstones (85.7% sensitivity) and correctly identified 85/89 without gallstones (95.5% specificity). The proportion (24/120) of uninterpretable scans from this pilot that used minimally trained clinicians (who are neither radiologists nor ultrasound technicians) indicates the need for additional training of POCUS operators. Nevertheless, this pilot feasibility study engenders optimism that in the Samoan setting nonexperts can be trained to use POCUS to diagnose cholelithiasis, thereby helping (along with stool cultures and Vi serology) to identify possible chronic S. Typhi carriers.

Tenacious Endemic Typhoid Fever in Samoa.

BACKGROUND: Typhoid fever has been endemic on the island nation of Samoa (2016 population, 195 979) since the 1960s and has persisted through 2019, despite economic development and improvements in water supply and sanitation. METHODS: Salmonella enterica serovar Typhi isolates from the 2 hospitals with blood culture capability and matched patient demographic and clinical data from January 2008 through December 2019 were analyzed. Denominators to calculate incidence by island, region, and district came from 2011 and 2016 censuses and from 2017-2019 projections from Samoa's Bureau of Statistics. Data were analyzed to describe typhoid case burden and incidence from 2008 to 2019 by time, place, and person. RESULTS: In sum, 53-193 blood culture-confirmed typhoid cases occurred annually from 2008 to 2019, without apparent seasonality. Typhoid incidence was low among children age < 48 months (17.6-27.8/105), rose progressively in ages 5-9 years (54.0/105), 10-19 years (60.7-63.4/105), and 20-34 years (61.0-79.3/105), and then tapered off; 93.6% of cases occurred among Samoans < 50 years of age. Most typhoid cases and the highest incidence occurred in Northwest Upolu, but Apia Urban Area (served by treated water supplies) also exhibited moderate incidence. The proportion of cases from short-cycle versus long-cycle transmission is unknown. Samoan S. Typhi are pansusceptible to traditional first-line antibiotics. Nevertheless, enhanced surveillance in 2019 detected 4 (2.9%) deaths among 140 cases. CONCLUSIONS: Typhoid has been endemic in Samoa in the period 2008-2019. Interventions, including mass vaccination with a Vi-conjugate vaccine coadministered with measles vaccine are planned.

CT findings of bilateral congenital absence of the long process of the incus.

Bilateral conductive deafness due to congenital absence of the long process of the incus (CALPI) is rare. The authors present the case of a patient with bilateral CALPI. To the best of our knowledge, this is the first reported case preoperatively diagnosed as bilateral CALPI by computed tomography. Multislice computed tomography is very useful for the diagnosis of minute abnormalities of the ossicles.

Asymmetric synthesis and determination of the absolute configuration of FK584, an agent for the treatment of overactive detrusor.

FK584[(-)-N-tert-butyl-4,4-diphenyl-2-cyclopentenylamine hydrochloride, (-)-4-HCl], a potential candidate for the treatment of overactive detrusor, was synthesized in a 4-step approach starting with Sharpless oxidation of cyclopentenol 6 (kinetic resolution). This epoxidation is a rare case in that the empirical rule does not work. Regio- and stereoselective introduction of tert-butylamine to the obtained epoxycyclopentanol 5 and subsequent conversion of the resulting diol to an olefin completed the synthesis. The absolute configuration of FK584 was determined to be S by X-ray crystallographic analysis of the salt of S-(+)-mandelic acid.

[Effects of thapsigargin and ryanodine on cochlear electrical potentials in guinea pigs examined by the perilymphatic perfusion method].

The effect of thapsigargin and ryanodine on cochlear microphonics (CM) and the endocochlear DC potential (EP) in the guinea pig was investigated by the perilymphatic perfusion method. These chemicals were considered to be pharmacological tools to reduce the amount of Ca2+ stored within the endoplasmic reticulum (ER), although the sites of their action were different; thapsigargin inhibits Ca2+ uptake of the ER, while ryanodine locks Ca2+ channels of the ER in an open state. Both CM and EP were measured with a glass microelectrode inserted into scala media. The amplitude of CM started to decrease soon after the beginning of thapsigargin perfusion and fell to 35% of the initial value in 30 minutes. Ryanodine, like thapsigargin, reduced the CM amplitude depending on the concentration between 1 x 10(-6) approximately 3 x 10(-5)M. These results suggest that Ca2+ ions which regulate the ciliar movements of outer hair cells are due not only to entry from extracellular fluid but to their release from the intracellular storage sites, probably through the mechanisms of Ca(2+)-induced Ca2+ release.

Agents for the treatment of overactive detrusor. V. Synthesis and inhibitory activity on detrusor contraction of N-tert-butyl-4,4-diphenyl-2-cyclopentenylamine.

N-tert-Butyl-4,4-diphenyl-2-cyclopentenylamine ((+/-)-3) was designed to restrict the conformation of terodiline 1 and was synthesized in a 6-step approach starting with diphenylacetaldehyde (10) or in a 4-step approach starting with 2,2-diphenyl-4-pentenoic acid (17). Using di-p-toluoyltartaric acid as a resolving agent, the synthetic (+/-)-3 was resolved into its optically pure forms, (-)- and (+)-3. The (-)-enantiomer (-)-3.HCl (FK584) showed about ten times more potent inhibitory activity on urinary bladder rhythmic contraction in rats (ED30 = 0.18 mg/kg, i.v.) than terodiline (ED30 = 1.9 mg/kg, i.v.), while the (+)-enantiomer (+)-3.HCl showed no inhibitory activity at 1.0 mg/kg i.v. Compound (-)-3.HCl (FK584) has pharmacological properties similar to those of terodiline, as evaluated by in vitro assay and is currently in clinical development for the treatment of overactive detrusor.

Magnetic resonance imaging and histology of a large cystic meningioma--case report.

A 9-year-old boy presented with a meningioma containing a large cyst. Magnetic resonance (MR) imaging demonstrated tumor cells in the solid part of the tumor, part of the cyst wall, and cyst septum. The presence of the tumor cells in the thin cyst wall or the cyst septum is important to recognize preoperatively, and MR imaging is very useful to differentiate intratumoral cysts from peritumoral cysts in meningiomas.

Agents for the treatment of overactive detrusor. VIII. Synthesis and pharmacological properties of 4,4-diphenyl-2-cycloalkenylamines including FK584 and 3,3- or 4,4-diphenylcycloalkylamines.

This article describes the synthesis of 4,4-diphenyl-2-cycloalkenylamines (3, 5a) including FK584 (S(-)-3a) and 3,3- or 4,4-diphenylcycloalkylamines (2, 4, 5b) and their inhibitory activities against detrusor contraction. The order of inhibitory activity (i.v.) of the N-tert-butylamine derivatives against urinary bladder rhythmic contraction in rats was as follows: S(-)-4,4-diphenyl-2-cyclopentenylamine (FK584, S(-)-3a) > 4,4-diphenylcyclohexylamine (5b) = R(-)-3,3-diphenylcyclopentylamine (R(-)-4) > or = 3,3-diphenylcyclobutylamine (2) > or = terodiline hydrochloride (HCl) (1) = RS(+/-)-4,4-diphenyl-2-cyclohexenylamine (5a) > R(+)-4,4-diphenyl-2-cyclopentenylamine (R(+)-3a) > or = S(+)-3,3-diphenylcyclopentylamine (S(+)-4). Although the inhibitory activity of FK584 and compounds R(-)-4 and 5b against detrusor contraction in vitro induced with KCl in guinea-pigs was less potent than that of terodiline HCl, their inhibitory activities against detrusor contractions in vitro induced by electrical field stimulation and carbachol were more potent than those of terodiline HCl.

Agents for the treatment of overactive detrusor. VII. Synthesis and pharmacological properties of 2,3- and 3,4-diphenylcyclopentylamines, 2,3-diphenyl-2-cyclopentenylamines, and related compounds.

As part of our search for new agents for the treatment of overactive detrusor, 2,3- and 3,4-diphenylcyclopentylamines (3), 2,3-diphenyl-2-cyclopentenylamines (4), and related compounds (5 and 18) were synthesized and evaluated for inhibitory activity (i.v.) against urinary bladder rhythmic contraction in rats. Among them, some compounds involving N-tert-butyl-2,3-diphenyl-2-cyclopentenylamine (4b) exhibited inhibitory activity against bladder contraction superior to that of terodiline (2). Mydriatic activity (i.v.) of compound 4b in rats, an index of its side effects due to antimuscarinic activity, was found to be relatively weak in comparison with its inhibitory activity against bladder contraction. The pharmacological profile of 4b was examined in comparison with that of terodiline. Most of the objective amines (3, 4, 5) were synthesized by preparation of Schiff bases from the corresponding cyclic ketones (6, 7, 8) and amines in the presence of TiCl4 in CH2Cl2 and subsequent reduction with NaBH4 in the presence of MeOH in one pot (method A).

Agents for the treatment of overactive detrusor. VI. Synthesis and pharmacological properties of acetamide derivatives bearing cyclic amines in N-substituents.

With the aim of improving of the efficacy and decreasing the side effects of oxybutynin (1), N-[(tetrahydro-3- or 4-pyridyl)methyl]-, N-(4-piperidyl)-, and N-(3- or 4-piperidylalkyl)-2-hydroxyacetamides (3a-n, 4a-g) and the related carboxamides (3o-r, 4h-k, 13', 17) were synthesized and evaluated for inhibitory activity against urinary bladder rhythmic contraction in rats and for mydriatic activity in rats. Some of these compounds were superior to oxybutynin in both inhibitory activity against bladder contraction and selectivity between inhibitory activity against bladder contraction and mydriatic activity. Among them, N-[(1,2,3,6-tetrahydro-4-pyridyl)methyl]- and N-[(1,2,3,6-tetrahydro-1-methyl-4-pyridyl)methyl]-2-hydroxy-2,2- diphenylacetamide (3e, 3f) exhibited the most potent inhibitory activity against bladder contraction (ED30 = 0.005 and 0.003 mg/kg i.v., respectively). Judging from the effect of 3e on detrusor contraction in vitro in guinea-pigs, it appeared that the inhibitory activity of 3e against bladder contraction in vivo was related mainly to its inhibitory activity against detrusor contraction in vitro induced with carbachol (antimuscarine-like activity). The selectivity (20-fold) of 3e between inhibitory activity against bladder contraction and mydriatic activity was greatly superior to that (0.48-fold) of oxybutynin. Compound 3e was synthesized by debenzylation (method E or F) of the corresponding N-[[1-(4-methoxybenzyl)-tetrahydro-4-pyridyl]methyl] derivative (3k), which was prepared by acylation (method B) of the corresponding (tetrahydro-4-pyridyl)methylamine (7k) or by reduction (method D) of the corresponding pyridinium chloride (14k) with NaBH4.

Agents for the treatment of overactive detrusor. IV. Synthesis and structure-activity relationships of cyclic analogues of terodiline.

A series of pyrrolidine derivatives were synthesized and examined for inhibitory activity on detrusor contraction in vivo. Among those compounds, 5,5-dimethyl-2-(2,2-diphenylethyl)-3-isopropylidenepyrrolidine+ ++ hydrochloride (41.HCl), 2-(2,2-di(4-fluorophenyl)ethylene)-5,5-dimethyl-3-isopropylidenepyrro lidine hydrochloride (42.HCl), (+)-5,5-dimethyl-2-(N,N-diphenylaminomethyl)-3-isopropylidenepy rrolidine hydrochloride (+)-(43a.HCl), (-)-5,5-dimethyl-2-(N,N-diphenylaminomethyl)-3-isopropylidenepy rrolidine hydrochloride (-)-(43a.HCl), and 2-(N,N-di(4-fluorophenyl)aminomethyl)-5,5-dimethyl-3-isopropylidenepy rrolidine methanesulfonate (43b.MsOH) showed stronger inhibitory activity on detrusor contraction than terodiline.

Agents for the treatment of overactive detrusor. III. Synthesis and structure-activity relationships of N-(4-amino-2-butynyl)acetamide derivatives.

A series of N-(4-amino-2-butynyl)acetamides were synthesized and examined for their inhibitory activity on detrusor contraction and mydriatic activity as an index of anticholinergic side effect. Among those compounds synthesized, (+)-2-cyclohexyl-N-(4-dimethylamino-2-butynyl)-2-hydroxy-2-phenylacet amide hydrochloride ((+)-13b.HCl), 2-cyclohexyl-2-hydroxy-N-(4-methylamino-2-butynyl)-2-phenylacetamide+ ++ hydrochloride (13c.HCl), N-(4-dimethylamino-2-butynyl)-2,2-diphenyl-2-hydroxyacetamide hydrochloride (14a.HCl), and 2,2-diphenyl-N-(4-ethylamino-2-butynyl)-2-hydroxyacetamide hydrochloride (14b.HCl) showed equipotent inhibitory activity on detrusor contraction to oxybutynin (1) and less mydriatic activity. Further evaluation of these compounds as an agent for the treatment of overactive detrusor has been examined.

Agents for the treatment of overactive detrusor. II. Synthesis and inhibitory activity on detrusor contraction of 1,1'-biphenyl-2,6-dicarboxylic acid diesters with an aminoalkyl group in the ester function.

A series of 1,1'-biphenyl-2,6-dicarboxylic acid diesters with an aminoalkyl group in the ester function were synthesized and examined for their inhibitory activity on detrusor contraction in vitro and in vivo. In the in vivo test, arrhythmia was observed as a side effect. Among those compounds synthesized, 2-methyl 6-[4-(1-methylpiperidinyl)] 3-hydroxy-5-methyl-2'-nitro-1,1'-biphenyl-2,6-dicarboxylate (18) showed strong inhibitory activity on detrusor contractions in vivo (ED50 = 0.54 mg/kg i.v., ED50 = 7.2mg/kg i.d.) and good separation from the side effect. Compound 18 was chosen for further pharmacological evaluation as an agent for the treatment of overactive detrusor.

Agents for the treatment of overactive detrusor. I. Synthesis and structure-activity relationships of 1,1'-biphenyl derivatives.

A series of 1,1'-biphenyl-2,6-dicarboxylic acid diesters were synthesized and examined for their inhibitory activity on guinea-pig detrusor muscle contraction at electrical field stimulation in vitro. Among them, 6-isopropyl 2-methyl 3-hydroxy-5-methyl-2'-nitro-(1,1'-biphenyl)-2,6-dicarboxylate, FR75513 (8a) was one of the potent compounds (IC50 = 3.3 x 10(-6) g/ml). This compound (8a) exhibited a strong inhibitory activity on detrusor contraction after intravenous administration in anesthetized rats (ID50 = 0.04 mg/kg).

Low activity of angiotensin-converting enzyme in cerebral microvessels of young spontaneously hypertensive rats.

Angiotensin-converting enzyme (ACE) activity was measured in microvessels prepared from cerebral cortices of 4-week-old spontaneously hypertensive rats (SHR). The Vmax value of the ACE activity in the cerebral microvessels of SHR was lower than that of Wistar Kyoto controls of the same age by 25% without difference in Km value for substrate. The low activity of ACE in the cerebral microvessels of young SHR indicates that in this animal model of hypertension the function of ACE is genetically altered in the cerebral microvessels, which may be correlated with the alteration of the cerebral microcirculation and pathogenesis of hypertension.

Angiotensin-converting enzyme activity is reduced in brain microvessels of spontaneously hypertensive rats.

Angiotensin -converting enzyme (ACE) activity in brain microvessels of spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) controls was measured. Cerebral microvessels, prepared from the cerebral cortices by the albumin flotation and glass bead filtration technique, were free of neuronal and glial elements. ACE activity in brain microvessels of SHR was lower than that of WKY. A Woolf - Augustinsson -Hofstee plot showed that the reduction of the enzyme activity in SHR was due to a 30% decrease in Vmax, without any change in Km for substrate. The decrease of ACE activity in brain microvessels of SHR may indicate an impairment of the central renin-angiotensin system and may be related to cerebral microvascular dysfunctions occurring in hypertension.