Review Article White Piedra: Review of 131 cases.

This study analyzes the clinical characteristics of patients diagnosed with White Piedra through a systematic review of cases in the literature. A sample of 131 subjects was considered, of which 91.6% were female and most were 18 years of age or younger. Most studies were conducted in Brazil, followed by India, and Mexico. The most common etiologic agent found was Trichosporon spp (34.3%). Most affected patients were asymptomatic (94.6%) and predisposing factors included long hair, use of a hair band or hair accessories, and wet hair. The most common clinical feature was the presence of nodules. The evaluation of treatment effectiveness was hindered by the scarcity of follow-up information in the majority of the studies. It is concluded that White Piedra infection is more common in young women and is associated with hair-related factors.

Epidemiology of neurocognitive disorders in adults from urban-marginalized areas: a door-to-door population-based study in Puente Piedra, Lima, Peru.

Background: In Latin America (LA), the prevalence of dementia is expected to triple to 150 million people by 2050. The 2020 Lancet Commission report identified several modifiable dementia risk factors, yet few social and environmental factors, most relevant to vulnerable regions of LA, were highlighted in this report. We sought to assess the epidemiology of neurocognitive disorders (NCD) in Puente Piedra, one of the most socially and economically vulnerable districts of Lima, the capital of Peru. Methodology: This was a cross-sectional door-to-door observational study that used two-stage household sampling. One young adult (30-59 years) and one older adult (>60 years) per household were enrolled. We collected demographic, clinical, and neurocognitive data. Addenbrooke's Cognitive Examination (young adults) and the RUDAS-PE (older adults) were used, classifying participants as cognitively normal, possible mild NCD, or possible major NCD. Results: We enrolled 247 participants (median age 46 years; 67% female). One-fourth had not completed secondary school and more than 50% completed only secondary school. Most participants were housewives (46%) and 21% did not have health insurance. The overall prevalence of possible NCD was 30% (25.6 and 41.8% among younger adults and older adults, respectively). Among younger adults, those ages 55-59 years more frequently had NCD (70%) compared to younger age ranges. Among older adults, only 3 subjects (4.5%) had major NCD. Conclusion: We found a high frequency of possible NCDs in a socially and economically vulnerable community in Lima, Peru, with younger adults showing levels of NCD higher than expected. Our findings support the need for health systems to incorporate cognitive screenings programs for NCD in younger ages. Future research on NCD would include younger populations, particularly in vulnerable communities.

Quantifying dispersal between two colonies of northern elephant seals across 17 birth cohorts.

Dispersal drives extinction-recolonization dynamics of metapopulations and is necessary for endangered species to recolonize former ranges. Yet few studies quantify dispersal and even fewer examine consistency of dispersal over many years. The northern elephant seal (Mirounga angustirostris) provides an example of the importance of dispersal. It quickly recolonized its full range after near extirpation by 19th century hunting, and though dispersal was observed it was not quantified. Here we enumerate lifetime dispersal events among females marked as pups at two colonies during 1994-2010, then correct for detection biases to estimate bidirectional dispersal rates. An average of 16% of females born at the Piedras Blancas colony dispersed northward 200 km to breed at Año Nuevo, while 8.0% of those born at Año Nuevo dispersed southward to Piedras Blancas. The northward rate fluctuated considerably but was higher than southward in 15 of 17 cohorts. The population at Piedras Blancas expanded 15-fold during the study, while Año Nuevo's declined slightly, but the expectation that seals would emigrate away from high density colonies was not supported. During the 1990s, dispersal was higher away from the small colony toward the large. Moreover, cohorts born later at Piedras Blancas, when the colony had grown, dispersed no more than early cohorts. Consistently high natal dispersal in northern elephant seals means the population must be considered a single large unit in terms of response to environmental change. High dispersal was fortuitous to the past recovery of the species, and continued dispersal means elephant seals will likely expand their range further.

Assessing parasite epidemiology in the epidemiological importance of Patagonian Late Holocene rockshelters using carnivore coprolites in the past: new data from Piedra Parada, Argentina.

The aim of this research was to analyse the variability of parasite assemblages on a small spatial scale, by examining carnivore coprolites from the archaeological site Campo Moncada 2 (CM2), Piedra Parada area, Chubut province, Argentina, and comparing the results with those previously obtained from the archaeological site Campo Cerda 1 (CCe1), located in the same area. Six carnivore coprolites from CM2 were analysed: 4 obtained in sub-level 2a and 2 obtained in sub-level 2a/b. Two radiocarbon dates associated with the coprolites placed the samples chronologically between 780 ± 80 and 860 ± 80 years before present. The rehydrated sediments were sieved and then allowed to sediment spontaneously. The sediment was used for parasitological examination under light microscopy. Conservative estimation of total parasite richness resulted in 21 parasitic taxa. The taxa with the highest fecal prevalence (>50%) corresponded to parasites prevalent in modern carnivores (Alaria sp., Toxocara cf. canis, Toxascaris sp., Eucoleus cf. aerophila, Trichuris sp. and Ancylostomatidae gen. sp.). Assuming that the fox coprolites are contemporaneous, the total fecal parasite richness estimated for CM2 and previously for CCe1 was similar. The high total parasite richness found suggests a network of host­parasite relationships that could include regional hunter-gatherers. The results obtained in carnivore coprolites allow us to infer a very diverse biological community in Piedra Parada area, so the regional caves and rockshelters could have a proportional epidemiological importance as parasite exchange nodes.

The epidemiological follow-up process for suspected and confirmed cases of COVID-19 in migrant shelters on the northern border of Mexico from July to December 2020: Between contagion underestimation and containment.

Background: Elements associated with an increased risk factor for the contagion of COVID-19 in shelters include the turnover and overcrowding of people, time spent in communal areas, daily supply needs, water availability, and sanitation levels. The "Report on the Effects of the COVID-19 Pandemic on Migrants and Refugees," shows that factors such as the shortage of food, supplies, water, sanitizing materials, spaces for healthy distancing, financial resources for rent and essential services, and the lack of medical or psychological care complicated providing care for migrants and applicants seeking international protection. Objective: We describe shelter operations regarding the detection and follow-up of suspected and confirmed COVID-19 cases showing mild symptoms among the migrant population housed in the border cities under study. Methods: We conducted semi-structured, in-depth interviews with study subjects (people in charge, managers, coordinators, shelter directors) from 22 migrant shelters, and 30 with key informants. We studied the cities of Tijuana (Baja California), Nogales (Sonora), Ciudad Juárez (Chihuahua), Piedras Negras (Coahuila), and Heroica Matamoros (Tamaulipas). The research was based on a qualitative methodological design with an ethnographic approach. The information collected was transcribed and systematized into two tables or analytical templates, one for interviews with study subjects, and another for interviews with key actors. Findings: Overall, seventy-eight registered shelters provided accommodation services for migrants in the five cities the study focused on: thirty-seven in Tijuana, five in Nogales, twenty-two in Ciudad Juárez, eight in Piedras Negras, and five plus a camp (six in total) in Matamoros. The major concentration of shelters was in Tijuana (47.4%) and Ciudad Juárez (28.2%). At the beginning of the pandemic, only a few shelter facilities met quarantine and isolation guidelines, such as having separate bathrooms and sufficient space to isolate the "asymptomatic" and "confirmed" from close "contacts". The lack of isolation space and the inability to support the monitoring of patients with COVID-19 posed a challenge for those housed in shelters, forcing many shelters to close or continue operating behind closed doors to avoid becoming a source of infection during the pandemic. Discussion and outlook: Contrary to speculation, during the onset of the pandemic northern border migrant shelters did not become sources of COVID-19 infection. According to the data analyzed from 78 shelters only seven had confirmed cases, and the classification of "outbreak" was applied only in two facilities. Contagion control or containment was successful as the result of following a preventive containment logic, including the isolation of all suspected but unconfirmed cases, without a clear understanding of the human and financial resources required to maintain isolation areas. However, shelters in the study implemented protocols for epidemiological surveillance, control, and prevention with elements that interfered with monitoring spaces, and processes that caused oversights that resulted in underestimating the number of cases. Limitations: Due to travel restrictions imposed to prevent and contain coronavirus infections it was impossible to stay on-site in the cities studied, except for Tijuana, or carry-out recordings of migrants' views in shelters.

Efficacy of topical vs combined oral and topical antifungals in white piedra of the scalp.

BACKGROUND: Topical antifungals are the most commonly used therapy in white piedra of the scalp. However, persistence and relapse of infection still pose a significant challenge. Systemic antifungals have been recommended to enhance the therapeutic response. AIMS: To compare the efficacy of topical antifungal alone versus combined topical and oral antifungals in the treatment of white piedra of the scalp. METHODS: Sixty patients with white piedra of the scalp were divided into 3 groups, each containing 20 patients. Group A received topical clotrimazole, group B received combined topical clotrimazole and oral itraconazole, and group C received combined topical clotrimazole and oral terbinafine. The treatment was continued until clearance of infection was confirmed by dermoscopic and mycological examination. Positive responders were followed up for 3 months after treatment. RESULTS: All the patients achieved complete clearance of infection. The median treatment time in group B was significantly shorter than group A (P < .001) and group C (P < .001), respectively. In addition, the median treatment time in group C was significantly shorter than group A (P = .002). No recurrence of infection was noted during follow-up period. CONCLUSION: The three modalities were effective in the treatment of white piedra of the scalp. The most rapid response was observed with the combined use of topical and oral azoles.

Simbolismos y enseñanzas médicas y sociales de unas máscaras precolombinas / Symbolisms and medical and social teachings of some pre-columbian masks

Se presentan 4 máscaras precolombinas, tres de las cuales son ecuatorianas y una colombiana. Las primeras son de cerámica y se adscriben a la cultura Jama-Coaque y la tercera de concha Spondylus prínceps no tiene adscripción a ninguna en particular del Ecuador prehispánico, por no existir un estudio sistemático en Ecuador sobre la relación de esas máscaras con sus culturas costeras, la colombiana es de cobre. La primera de cerámica ecuatoriana por su tamaño, peso y elementos agregados ­ un material blanco que simula los dientes, tres piedras verdes que parecen los ojos y una incrustación sublabial, un bezote ­ hacen pensar en una máscara mortuoria de un personaje de poder y alto estatus social; la segunda de cerámica por presentar dieciséis nódulos faciales remite al observador a la llamada verruga peruana o bartonelosis, la tercera ecuatoriana fue elaborada posiblemente como un elemento votivo o de ofrenda para exhibir poder o invocar fuerza o protección dado el carácter de gran valor simbólico de esa concha roja. La máscara de cobre del Cauca medio o Quimbaya, en razón a su material, peso y color, con bastante probabilidad fue usada como adorno colocado sobre el pecho del personaje poderoso o de elevado estatus. Se compara la máscara con bartonelosis con otras dos que el autor ya había documentado, la de concha con otra del mismo tipo de material, la máscara de cobre con una pequeña de piedra jadeíta se referencia con una calavera enmascarada que el autor tuvo la oportunidad de estudiar hace varios años. Se concluye sugiriendo los usos tradicionalmente asignados a las máscaras: festivos, mortuorios y como adornos corporales para resaltar el poder de quien las exhibe. Las máscaras con la erupción tipo nódulos debieron jugar un papel similar a las estatuillas en cerámica y piedra que representan patologías con tanto realismo en el arte prehispánico, pudiendo ser una forma de enseñar, dentro de un pensamiento médico empírico analógico, como lo son los moldes en cera, las fotografías, los dibujos y pinturas en la medicina moderna basada en un pensamiento empírico analítico.

Four pre-Columbian masks are presented, three of which are Ecuadorian and one Colombian. The Ecuadorian masks are made of ceramics and ascribe to the Jama-Coaque culture and the third is made of Spondylus prínceps shell, and does not have any ascription to any particular Ecuadorian pre-Hispanic coastal culture, for no systematic study was conducted in Ecuador on the relationship of those masks and coastal cultures. The Colombian mask is made of copper. The first ceramic mask, for its size, weight and additional elements ­ a white material that simulates teeth, three green stones that simulate eyes and a lower labial incrustation, "bezote"- makes one recall a death mask of an individual with significant power and high social status; the second ceramic mask, features sixteen facial nodules which refer the observer to the Peruvian wart or bartonellosis, the third mask was possibly created as a volitional or offering element to exhibit power or evoke the force or protection given the great symbolic value of that red shell. The middle Cauca Quimbaya copper mask was most probably used as an ornament for the chest of a powerful or high class person given its material, weight and color. The mask that resembles bartonellosis is compared with other two masks the author had already examined. The shell mask was compared with another made of the same type of shell, the copper mask with a small jadeite stone mask, a masked skull that the author had the opportunity to examine several years ago.Finally, these interpretations suggest that in addition to the uses traditionally assigned to the masks: festive, funerary and as body adornments to portray the power of the wearer, the masks with the multiple nodular lesions must have served a role similar to that of the ceramic and stone miniature statues which depict pathologies, featuring great realism in pre-Hispanic art, as a way of teaching through an analogical empirical medical thought, the same role played by wax molds, photographs and drawings and paintings in modern medicine, also based on analytical empirical thought.

The Piedra Chamana fossil woods and leaves: a record of the vegetation and palaeoenvironment of the Neotropics during the late middle Eocene.

BACKGROUND AND AIMS: The Piedra Chamana fossil forest in northern Peru is an assemblage of angiosperm woods and leaves preserved in volcaniclastic rocks dated to 39 Mya (late Middle Eocene). We analysed the anatomical and morphological features of the fossils to reconstruct the palaeoenvironment during this time of global warmth, taking advantage of the co-occurrence of woods and leaves to compare different proxies and analytical approaches. METHODS: Wood characters analysed include vessel-related functional traits, traits linked to Baileyan trends, and quantitative features such as vessel diameter and density. Diameter-distribution and diameter and position plots are used to represent vessel diameter and arrangement. Leaf margin and area analysis provides additional climate estimates. KEY RESULTS: The fossil woods show many similarities with modern tropical-forest woods and tropical fossil-wood assemblages; closest correspondence within the Neotropics is to semi-deciduous lowland tropical forest with moderate precipitation (~1000-1200 mm). Features unusual for the modern South American tropics are mainly vessel-related characters (semi-ring porosity, grouped vessels, helical vessel thickenings, short vessel elements) linked to water stress or seasonal water availability. Leaf analysis indicates mean annual temperature of 31 °C (n = 19, 100 % entire-margined) and mean annual precipitation of 1290 mm (n = 22, predominantly microphylls and notophylls). CONCLUSIONS: The palaeovegetation was clearly lowland tropical forest with a dry aspect, but anomalous aspects of the wood anatomy are consistent with the high temperatures indicated by the leaves and are probably explained by differences in seasonality and water stress compared to the present-day Neotropics. A close modern analogue may be in very seasonal regions of Asia. Pronounced monsoonal (summer-rain) conditions may relate to a location (palaeolatitude of 13°S) outside the near-equatorial tropics.

White piedra, black piedra, tinea versicolor, and tinea nigra: contribution to the diagnosis of superficial mycosis.

Superficial mycoses are fungal infections restricted to the stratum corneum and to the hair shafts, with no penetration in the epidermis; they are: white piedra, black piedra, tinea versicolor, and tinea nigra. This study presents images of mycological tests performed in the laboratory, as well as exams performed at the authors office, in order to improve the dermatologist's knowledge about the diagnosis of these dermatoses, which are common in many countries.

White piedra, black piedra, tinea versicolor, and tinea nigra: contribution to the diagnosis of superficial mycosis

Abstract Superficial mycoses are fungal infections restricted to the stratum corneum and to the hair shafts, with no penetration in the epidermis; they are: white piedra, black piedra, tinea versicolor, and tinea nigra. This study presents images of mycological tests performed in the laboratory, as well as exams performed at the authors office, in order to improve the dermatologist's knowledge about the diagnosis of these dermatoses, which are common in many countries.

Tricomicosis axilar: diagnóstico en imágenes, clínica, luz de Wood y dermatoscopia / Trichomycosis axillaris: clinical, Wood lamp, and dermoscopic diagnostic images

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Long-term pubic dermatitis diagnosed as white piedra.

The case of a 58-year-old man with a pruritic rash involving the pubic area that had been undiagnosed for 30 years is presented. At least 15 different primary care physicians and dermatologists evaluated the patient during this time period. Multiple treatments were unsuccessful and a definitive diagnosis was not rendered. Wood lamp evaluation of the pubic area revealed hair shaft concretions that were confirmed on histologic evaluation to be white piedra (WP). The patient was successfully treated with topical ketoconazole and the eruption completely resolved. Our case raises awareness of the use of Wood lamp and dermoscopy to evaluate for parasitic infections of the pubic hair shafts when nonspecific dermatitis presents in this area.

An Unusual Case of White Piedra Due to Trichosporon inkin Mimicking Trichobacteriosis.

White piedra is a superficial mycosis characterized by soft, white-to-tan, irregular nodules attached to the hair shafts. A 36-year-old man presented with small lumps in his pubic hair, without any other symptoms. The clinical features were suggestive of trichobacteriosis. Pathology analysis of the infected hair revealed that the concretions surrounding the hair shaft were full of fungal elements, parts of which had invaded into the cuticle. Culture on Sabouraud dextrose agar grew creamy, yellow-white colonies identified as Trichosporon inkin by the sequence of the nuclear ribosomal intergenic spacer region. The condition was treated by shaving the pubic hair and administering antifungal therapy (oral itraconazole and topical ketoconazole).