Water, Sanitation, and Hygiene (WaSH) insecurity in unhoused communities of Los Angeles, California

BACKGROUND

Access to water and sanitation is a basic human right; however, in many parts of the world, communities experience water, sanitation, and hygiene (WaSH) insecurity. While WaSH insecurity is prevalent in many low and middle-income countries, it is also a problem in high-income countries, like the United States, as is evident in vulnerable populations, including people experiencing homelessness. Limited knowledge exists about the coping strategies unhoused people use to access WaSH services. This study, therefore, examines WaSH access among unhoused communities in Los Angeles, California, a city with the second-highest count of unhoused people across the nation.

METHODS

We conducted a cross-sectional study using a snowball sampling technique with 263 unhoused people living in Skid Row, Los Angeles. We calculated frequencies and used multivariable models to describe (1) how unhoused communities cope and gain access to WaSH services in different places, and (2) what individual-level factors contribute to unhoused people's ability to access WaSH services.

RESULTS

Our findings reveal that access to WaSH services for unhoused communities in Los Angeles is most difficult at night. Reduced access to overnight sanitation resulted in 19% of the sample population using buckets inside their tents and 28% openly defecating in public spaces. Bottled water and public taps are the primary drinking water source, but 6% of the sample reported obtaining water from fire hydrants, and 50% of the population stores water for night use. Unhoused people also had limited access to water and soap for hand hygiene throughout the day, with 17% of the sample relying on hand sanitizer to clean their hands. Shower and laundry access were among the most limited services available, and reduced people's ability to maintain body hygiene practices and limited employment opportunities. Our regression models suggest that WaSH access is not homogenous among the unhoused. Community differences exist; the odds of having difficulty accessing sanitation services is two times greater for those living outside of Skid Row (Adj OR: 2.52; 95% CI: 1.08-6.37) and three times greater for people who have been unhoused for more than six years compared to people who have been unhoused for less than a year (Adj OR: 3.26; 95% CI: 1.36-8.07).

CONCLUSION

Overall, this study suggests a need for more permanent, 24-h access to WaSH services for unhoused communities living in Skid Row, including toilets, drinking water, water and soap for hand hygiene, showers, and laundry services.

A quantitative PCR assay for antiviral activity screening of medicinal plants against Herpes simplex 1

Herpes simplex virus one is one of the most prevalent pathogens worldwide. Strains resistant to current treatment have been reported, so it is necessary to search for new antiviral molecules. The most common method to quantify antiviral activity from natural products is the plaque reduction assay, a technically demanding method. In order to provide a simple alternative to this method, we have established a procedure for viral quantification by qPCR, and coupled with a cytotoxicity evaluation system using resazurin. In this way, it is possible to obtain both the estimation of cytotoxicity and the antiviral activity simultaneously, allowing rapid screening of plant extracts. Ten out of twenty-eight Paraguayan medicinal plant extracts evaluated using this method showed antiviral activity, and the EC₅₀, CC₅₀, and SI values were calculated for each extract. Our experience supports the employment of the described method for a rapid identification of plant extracts with antiviral activity.

Antidepressant-like effect of Kyllinga brevifolia rhizomes in male mice and chemical characterization of the components of the active ethyl acetate fraction

ETHNO-PHARMACOLOGICAL RELEVANCE

Kyllinga brevifolia rhizomes (Cyperaceae) are used in Paraguayan traditional medicine as a refreshing beverage, and is claimed to own digestive, diuretic, sedative, tonic, antispasmodic and sudorific properties. We have previously reported that its hydro- ethanolic rhizome extract possess sedative, anxiolytic and anti-aggressive-like effects in mice. However, information on its potential for treatment of syndromes associated with mood disorders is scarce.

AIM OF THE STUDY

The purpose of this study is to characterize the putative antidepressant-like effects of the hydro-ethanolic extract (CEKb) and the ethyl acetate fraction (KbF-ethyl-ac) obtained from the rhizome of K. brevifolia (Rottb) on male mice exposed to forced swimming test. Also, chemical characterization of the components of the active ethyl acetate fraction was described.

MATERIALS AND METHODS

The antidepressant-like effects of CEKb and KbF-ethyl-ac were measured using the forced swimming test (FST) performance of male mice in single (acute), short-term and chronic modalities. Treatments in all modalities were made 1h before swimming test. The KbF-ethyl-ac was analyzed by LC-DAD-ESI-MS and LC-ESI-MS/MS in order to identify the active components.

RESULTS

A single doses (1.0, 10.0 and 100.0mg/kg, p.o; p<0.05) of CEKb, in male mice provoked a significant reduction of the immobility time. Such effect was also observed with oral short-term treatment (7 days) with doses of 10.0 and 100.0mg/kg/day (p<0.05) of CEKb. Moreover, in the treatments during 14 days with doses of 1.0 (p<0.05), 10.0 (p<0.05), and 100.0 (p<0.001) mg/kg, p.o, of CEKb, a statistically significant reduction of the immobility time were induced. Additionally, in a different set of experiments acute dose of 1.0 (p<0.05) and 10.0 (p<0.01) mg/kg, p.o, of KbF-ethyl-ac in male mice, a significant reduction of the immobility time were provoked. Likewise, short-term treatment (7 days) with 1.0, and 10.0mg/kg (p<0.05); and after 14 days of treatment with 0.01 (p<0.01) 0.1 (p<0.001), 1.0 (p<0.001), and 10.0 (p<0.05) mg/kg of KbF-ethyl-ac in male mice, a statistically significant reduction of the immobility time, were observed. Imipramine 32mg/kg/days, i.p, induced a statistically significant reduction of immobility time and was used as positive control to validate the method employed. Moreover, it was noted important differences in the onset of the antidepressant-like effect in the FST, depending on the modality of treatment with CEKb or KbF-ethyl-ac (acute, short-term or chronic). Both, efficacy and potency were higher when repeated administration of CEKb was used, and surprisingly the efficacy of 1.0mg/kg of KbF-ethyl-ac (14 days) was similar to imipramine. The main constituents of the KbF-ethyl-ac were identified as catechins and their dimers by LC-DAD-ESI-MS and LC-ESI-MS/MS, according to their UV and MS spectra, as compared with the literature data. These results indicate an important antidepressant-like profile of action for the CEKb and KbF-ethyl-ac; and meanwhile, this effect may partially reside on catechins and their dimers isolated from the KbF-ethyl-ac.

CONCLUSION

These findings indicate that K. brevifolia exerts antidepressant -like effects in mice and suggest its potential usefulness for the treatment of depression in humans and encourage us to pursue the isolation of the molecules associated to the effect observed in CEKb and KbF-ethyl-ac, and to determine the mechanism of antidepressant-like effect of Kyllinga brevifolia using adequate complementary test.

Antihypertensive effect of nuatigenin-3-O-β-chacotriose from Solanum sisymbriifolium Lam. (Solanaceae) (ñuatî pytâ) in experimentally hypertensive (ARH+DOCA) rats under chronic administration

The aim of the study is to assess the hypotensive properties of the hydro-ethanolic crude root extract (CRE), the n-butanol fraction (F(BtOH)) and nuatigenin-3-O-β-chacotriose, from Solanum sisymbriifolium Lam., in adrenal regeneration hypertension+deoxycorticosterone acetate (ARH+DOCA) rats, following a chronic administration. The roots of S. sisymbriifolium Lam. (Solanaceae) were extracted by reflux with ethanol-water 7:3 and the active extract was fractionated by bioassay-guided liquid-liquid separation. Nuatigenin-3-O-β-chacotriose (B(3-1)) was identified as the main hypotensive compound from the crude drug by spectroscopic methods. Immature Wistar rats of both sexes were submitted to both surgery and deoxycorticosterone acetate treatment to obtain adrenal regeneration hypertensive rats (ARH+DOCA). Different groups of experimentally induced hypertensive rats were randomly allotted and received during 16 weeks a daily oral administration of 1% saline solution (0.1 mL/100g body weigh), 100.0 mg/kg of CRE, 10.0, 30.0 and 50.0 mg/kg of F(BtOH), and 1.0 mg/kg of B(3-1), respectively. In addition, two groups of ARH+DOCA rats were randomly assigned to receive either B(3-1) (1.0 mg/kg/day) or 1% of saline solution (0.1 mL/100g body weight/day) for 7 weeks and then a cross over procedure was performed in order to complete the 16th-week treatment. After 16 weeks of oral administration of crude root extract (CRE), butanolic fraction (F(BtOH)) and nuatigenin-3-O-β-chacotriose (B(3-1)) a significant reduction of blood pressure value was induced in hypertensive animals (ARH+DOCA) in comparison to the control group receiving 1% saline solution, at the end of experiment. Administration of B(3-1) (1.0 mg/kg/day p.o.) to ARH+DOCA rats provoked a significant reduction of blood pressure, observed gradually from 5th week (p<0.05) to the end of the 16th week period of treatment (p<0.01). Moreover, in a cross over design it was observed that the reduction of blood pressure to normotensive condition is associated to B(3-1). The latest demonstrated that the blood pressure-lowering effect, in clearly hypertensive animals, is reversible and depend upon administration of nuatigenin-3-O-β-chacotriose (B(3-1)). Our results demonstrated that daily oral administration of CRE, F(BtOH) and nuatigenin-3-O-β-chacotriose from S. sisymbriifolium for a 16-week period exhibits an antihypertensive effect in experimentally hypertensive (ARH+DOCA) rats.

The antidepressant-like effects of Aloysia polystachya (Griseb.) Moldenke (Verbenaceae) in mice

The aim of the present work is to evaluate the putative antidepressant-like effects of a hydro-ethanolic extract (CEAp) and their fractions from the aerial parts of Aloysia polystachya (Griseb.) Moldenke (Verbenaceae) on the performance of male mice in the forced swimming test (FST). A single dose (100.0mg/kgp.o.) of CEAp, in male mice provoked a significant reduction of the immobility time (p<0.01). Such effect was also observed with short-term treatment (7 days) with single doses of 1.0 (p<0.01), 10.0 (p<0.05) and 100.0 (p<0.05)mg/kg/day of CEAp. Additionally, in a different set of experiments, repeated administration in a 24-h period (24, 18 and 1h before swimming test) with doses of 1.0 (p<0.05) and 10.0 (p<0.05)mg/kg p.o., of CEAp and 10.0mg/kgp.o., (p<0.05) of ethyl acetate fraction, provoked significant reduction of the immobility time of male mice in the FST. Moreover, it was noted important differences in the onset of the antidepressant-like effect in the FST, depending on the modality of treatment with CEAp (acute, short-term or repeated). Both, efficacy and potency were higher when repeated administration of CEAp was used, and surprisingly the dose of 10mg/kg (24, 18 and 1h before swimming test) was more effective than imipramine. In the same way, the short term administration (7 days) improved significantly efficacy and potency of the CEAp in comparison to a single dose treatment. The ethyl acetate fraction submitted to TLC demonstrated that main and minor components are phenolics and terpenes, respectively. In addition, this fraction gives a negative Shinoda's test for flavonoids. These results indicate an antidepressant-like profile of action for the hydro-ethanolic extract and the component(s) of the ethyl acetate fraction obtained from A. polystachya, which deserve further investigation.

A new lupane caffeoyl ester from Hippocratea volubilis

The extract of the rootbark of Hippocratea volubilis afforded a new triterpene caffeoyl ester, lupeol caffeate (1). Its structure was determined by means of spectroscopic evidence.

Isolation of hypotensive compounds from Solanum sisymbriifolium Lam

The crude hydroalcoholic root extract (CRE) of Solanum sisymbriifolium Lam. has formerly been shown to have hypotensive activity both in normo-and hypertensive rats. Hypotensive activity-guided fractionation of the CRE was performed in anaesthetized normotensive rats, which led to the isolation of the active principles. The intravenous (i.v.) and intraperitoneal (i.p.) values of the CRE in mice were found to be, respectively, 343 and 451 mg/kg, and no lethal effect was caused by doses up to 5.0 g/kg when administered by oral route. Depression of locomotion, increase of breathing rate and piloerection was observed in a general behavior test with doses up to 200 mg/kg i.p., and 1000 mg/kg p.o., respectively. Increase in the gastrointestinal transit was found using 0.1 g/kg, whereas at doses of 0.5 and 1 g/kg, no significant activity was observed in comparison with the control mice. Hexanic and butanolic fractions induced a remarkable hypotension in anaesthetized normotensive rats in doses of 1, 5, 7.5 and 10 mg/kg i. v. Two compounds isolated from the butanolic fraction induced a significant decrease of the blood pressure, HR, amplitude of the ECG and breathing rate when injected in a dose of 1 mg/kg i.v; and both systofic and diastolic, blood pressures were affected in a proportional mode. The hypotensive effect of the two compounds were not influenced by pretreatment with atropine and propranolol; and the pressor response to noradrenaline was not affected by any of them which suggests that neither a direct muscarinic activity, beta-adrenoceptor activation nor decrease of sympathetic vascular tone (sympatholitic activity) are probably involved in the mechanism of hypotension. The present study shows that the CRE of S. sisymbriifolium contains at least two hypotensive compounds whose characterization is under way.

Insecticidal activity of Maytenus species (Celastraceae) nortriterpene quinone methides against codling moth, Cydia pomonella (L.) (Lepidoptera: tortricidae)

The insecticidal effects of nortriterpene quinone methides (pristimerin, tingenonee, and 20-alpha-hydroxytingenone) are reported for the first time. The natural products were isolated from Maytenus sp. (Celastraceae) and their effects tested on larvae of codling moth (Cydia pomonella, Lepidoptera: Tortricidae). The three metabolites produce the same effects on codling moth larvae that azadirachtin does, although at higher concentrations. 20-alpha-Hydroxytingenone was the most active compound, showing lethal, antifeedant, and insect growth regulation activities. Pristimerin showed also a high antifeedant activity together with its molt effect suppression. Tingenone showed the lowest activity. The differences in the activity of the three products are related to the structure of the E ring.