Meaning in life, goals, and adherence to antiretroviral treatment in people living with HIV.

Patients living with HIV who do not adhere to antiretroviral treatment (ART) have a high viral load, increasing the risk of developing AIDS, as well as new treatment-resistant strains. There are several psychological factors that must be studied to understand the reasons for non-adherence to ART. We studied whether the goals reported by patients with HIV, as well as their sense of meaning in life, influence ART adherence in a sample of adult patients attending HIV outpatient care in Mexico. Participants completed the Antiretroviral Treatment Adherence Assessment Questionnaire, the Dimensional Scale of Meaning in Life and were asked to write both short-term and long-term goals. The most frequent goals reported were those categorized as "personal development," followed by "being healthy." Participants with the highest adherence had more short-term "personal development" goals. Moreover, they showed the lowest levels of existential vacuum (lack of meaning in life). These variables predicted treatment adherence. We conclude that the design of programs to improve ART adherence should promote the establishment of personal development goals and offer tools that allow having a sense of meaning in life to reduce AIDS-related complications.

Menopause-related symptoms, meaninglessness, and life satisfaction in Mexican women.

We studied the influence of meaninglessness and life satisfaction on menopause-related symptoms in 342 middle-aged Mexican women. They completed the Greene Climacteric Scale, the Dimensional Scale of the Meaning of Life, and the Satisfaction with Life Scale. Psychological symptoms were predicted by meaninglessness and life satisfaction; somatic symptoms only by meaninglessness; and the sexual symptom by meaninglessness and by the menopausal status. These findings may be useful in designing strategies to help women find meaning and satisfaction in their lives and thereby enable them to experience menopause under optimum conditions.

Evaluation of an anti-stigma intervention for Mexican psychiatric trainees.

BACKGROUND: There is research evidence regarding the presence of stigmatising attitudes in psychiatrists towards people with mental illness, but a lack of studies and interventions focused on this issue in low and middle-income countries. AIMS: To assess the feasibility of implementing an anti-stigma intervention for Mexican psychiatric trainees, and its potential effects. METHODS: This study comprised a pre-post design with outcome measures compared between baseline and 3-month follow-up. Quantitative outcome measures were used to evaluate the potential effects of the intervention, whilst the process evaluation required the collection and analysis of both quantitative and qualitative data. RESULTS: Twenty-nine trainees (25% of those invited) participated in the intervention, of whom 18 also participated in the follow-up assessment. Outcome measures showed the intervention had moderately large effects on reducing stereotypes and the influence of other co-workers on trainees' own attitudes. The main mechanisms of impact identified were recognition of negative attitudes in oneself and colleagues, self-reflection about the impact of stigma, one's own negative attitudes and recognition of one's ability to make change. Participants accepted and were satisfied with the intervention, which many considered should be part of their routine training. However, trainees' work overload and lack of support from the host organisation were identified as barriers to implement the intervention. CONCLUSIONS: A brief anti-stigma intervention for Mexican psychiatric trainees is feasible, potentially effective, well accepted and was considered necessary by participants. This study also suggests mechanisms of impact and mediators should be considered for developing further interventions, contributing to reducing the damaging effects that mental health-related stigma has on people's lives.

Mexican Psychiatric Trainees' Attitudes Towards People with Mental Illness: A Qualitative Study.

Despite their training, psychiatrists have been found to have negative attitudes towards people with mental illness, including the patients they treat. Similarly, studies focused on service users have identified psychiatrists as a source of stigma. Even though negative attitudes in psychiatrists have been identified in different countries and settings, in Mexico the attitudes of these professionals have never been assessed. Because of this, we invited psychiatric trainees from a hospital in Mexico to participate in individual interviews to describe their opinions regarding mental health-related stigma, to evaluate their attitudes towards people with mental illness and to identify factors that could be influencing their attitudes. Interviews were audio recorded, transcribed and analysed using thematic analysis. A total of 29 trainees participated in the study. The results suggested that trainees recognised psychiatrists can have negative attitudes towards people with mental illness, such as poor empathy, judgement and labelling, and mainly towards patients considered difficult and with borderline personality disorder. Participants recognised these attitudes can influence their relationship with patients, and considered it is necessary to develop interventions to improve their own attitudes and reduce mental health stigma. From this study we concluded Mexican psychiatrists are not free from stigma towards people with mental illness. However, Mexican psychiatric trainees are interested in improving their attitudes and reactions towards their patients.

Estructura factorial de la versión mexicana del Inventario de Depresión de Beck II en población general del sureste mexicano / Factorial Structure of Mexican Version of the Beck Depression Inventory II in General Population of Mexican Southeastern

RESUMEN Objetivo: Determinar la estructura factorial del cuestionario BDI-II en población abierta del sureste de México. Método: Se recolectaron aplicaciones del BDI-II en una muestra de 3701 habitantes del municipio de Oaxaca de Juárez de siete colonias diferentes. Se describen las características generales de la población y se contrasta el ajuste de la estructura a los datos de la muestra con cinco estructuras factoriales propuestas en estudios de validación psicométrica anteriores por medio del análisis factorial confirmatorio. Así mismo, se determinó la confiabilidad total de la prueba. Resultados: El análisis confirmatorio muestra que los datos se ajustan a la estructura teórica propuesta por Beck, Steer y Brown con dos modificaciones. Las otras estructuras analizadas tienen índices de ajuste menos satisfactorios. La confiabilidad total de la prueba fue de .92. Discusión y conclusión: Se discuten algunas razones por las cuales los resultados de este trabajo difieren de los reportados en investigaciones anteriores y la importancia del análisis psicométrico adecuado para pruebas utilizadas en distintas poblaciones de estudio.

ABSTRACT Objective: To determine the factorial structure of the BDI-II questionnaire in the open population of southeastern Mexico. Method: BDI-II applications were collected in a sample of 3,701 inhabitants of the municipality of Oaxaca de Juarez from seven different colonies. The general characteristics of the population are described and the adjustment of the structure to the data of the sample is contrasted with five factorial structures proposed in previous psychometric validation studies by means of confirmatory factor analysis. Likewise, the total reliability of the test was determined. Results: The confirmatory analysis shows that the data conform to the theoretical structure proposed by Beck, Steer and Brown with two modifications. The other structures analyzed have less satisfactory adjustment indices. The total reliability of the test was .92. Discussion and conclusion: We discuss some reasons why the results of this work differ from those reported in previous research and the importance of adequate psychometric analysis for tests used in different study populations.

Actitudes hacia la donación de órganos postmortem en adultos de Xalapa y Cuernavaca / Attitudes towards posthumous organ donation in adults from Xalapa and Cuernavaca

Resumen El trasplante de órganos representa la única alternativa para sobrevivir o mejorar la calidad de vida de muchos pacientes; sin embargo, existe una grave escasez de órganos para trasplante. En el presente estudio se exploraron las actitudes hacia la donación de órganos postmortem en México, comparando los resultados por sexo, edad y escolaridad. Se aplicó el cuestionario de Actitudes hacia la Donación de Órganos Postmortem (ADOP) a 897 adultos, el cual consta de tres factores: Actitudes Favorables, Actitudes Desfavorables y Desconfianza. Las pruebas estadísticas usadas fueron chi cuadrada, t de student, ANOVA de una vía, y regresión logística. Las mujeres, los más jóvenes y los de mayor escolaridad se mostraron más dispuestos a donar sus órganos al morir, y tuvieron los puntajes más bajos en los factores de Actitudes Desfavorables y Desconfianza. Al comparar los resultados de los factores del ADOP, se observó que los participantes reconocen la importancia de la donación de órganos. Los resultados pueden servir para sensibilizar a la población, particularmente a los individuos de mayor edad y baja escolaridad, con el fin de mejorar la tasa de donación de órganos.

Abstract Organ transplantation represents the only alternative to survive or improve the quality of life of many patients; however, there is a serious shortage of organs to be transplanted. The present study explored the attitudes towards postmortem organ donation in Mexico, comparing the results by gender, age and schooling. The Attitudes towards Postmortem Organ Donation Questionnaire (ADOP in Spanish) was applied to 897 adults, which is composed of three factors: Favorable Attitudes, Unfavorable Attitudes, and Distrust. Women, the youngest participants and those with higher education were more willing to donate their organs when they die, and had the lowest scores on the Unfavorable Attitudes and Distrust factors. The statistical tests used were chi square, student t test, one-way ANOVA, and logistic regression. When comparing the results among the three factors of the ADOP, it was shown that participants recognize the importance of organ donation. The results may be useful to sensitize the population, particularly to older individuals and those with low schooling, in order to improve organ donation rates.

Propiedades psicométricas de la escala de Locus de Control de la Salud en Dios en una muestra de mexicanos con diabetes mellitus tipo 2 / Psychometric properties of the God Locus of Health Control scale in a sample of mexicans with type 2 diabetes mellitus

En este estudio se obtuvo evidencia de validez y confiabilidad de la escala de Locus de Control de la Salud en Dios (GLHC) en una muestra de 539 adultos mexicanos con diabetes mellitus tipo 2. El análisis de validez se basó en el análisis del contenido de los ítems y de la estructura interna del GLHC. El primer procedimiento estuvo a cargo de seis expertos, quienes evaluaron la pertinencia de la adaptación de los ítems. El segundo procedimiento fue un análisis factorial confirmatorio de grupo múltiple, de acuerdo al sexo y edad, a fin de evaluar la invarianza de medición del GLHC. Finalmente, la confiabilidad fue calculada mediante los coeficientes ω y H. El análisis factorial confirmatorio demostró una estructura de un solo factor con seis ítems, interpretable para la población de estudio con invarianza de medición por sexo, aunque deben tomarse precauciones al interpretar comparaciones por grupos de edad. La confiabilidad del constructo obtuvo magnitudes elevadas (>.90). Los resultados indican que la GLHC puede brindar información válida y confiable para valorar el locus de control de la salud en Dios para mexicanos con diabetes mellitus tipo 2.

The validity and reliability of the God Locus of Health Control (GLHC) scale were determined in a sample of 539 Mexican adults with type 2 diabetes mellitus. The validity analysis was based on the analysis of the GLHC scale's items content and internal structure. The first procedure was conducted by six experts who evaluated the pertinence of the items adaptation. The second procedure consisted of a multiple-group confirmatory factor analysis by gender and age, aimed to evaluate the GLHC scale's measurement invariance. Finally, reliability was estimated by means of coefficients ω and H. The confirmatory factor analysis demonstrated a six-item unifactorial structure, interpretable for the study population with measurement invariance by gender. Nevertheless, precautions should be taken when interpreting age-group comparisons. The magnitude of the construct reliability was high (>0.90). The results indicate that the GLHC scale may provide valid and reliable information to assess the God Locus of Health Control in Mexicans with type 2 diabetes mellitus.

¿Por qué los médicos no utilizan en forma temprana la insulinización en pacientes con diabetes mellitus tipo 2?: Un estudio cualitativo en una ciudad mexicana / Why don't doctors use early insulinization therapy in patients with diabetes mellitus type 2?: A qualitative approach in a Mexican city

RESUMEN La terapia de insulinización temprana ha demostrado ser un auxilio eficaz para mejorar el control a largo plazo y la calidad de vida de pacientes con diabetes mellitus tipo 2. Sin embargo, tanto los pacientes como los médicos presentan barreras al uso de esta alternativa terapéutica. El presente estudio utiliza un abordaje cualitativo para explorar las barreras a la insulinización temprana que tiene el personal médico del sector público en la ciudad de Xalapa, Veracruz, México. Entre los años 2015 y 2016, se realizaron entrevistas en profundidad a médicos generales y especialistas que brindaban atención primaria a pacientes con diabetes mellitus tipo 2. Las entrevistas transcritas fueron analizadas para extraer y esquematizar las categorías y subcategorías de las barreras del personal de salud, las cuales se agruparon en tres categorías que fueron ejemplificadas con extractos del discurso de los participantes: barreras propias del personal médico, barreras que surgen en la relación médico-paciente, y obstáculos institucionales. Se discuten los posibles usos del esquema obtenido, así como algunas propuestas de solución generadas por los participantes del estudio.

ABSTRACT Early insulinization therapy is regarded as an efficient aid to improve long term control and quality of life in patients with diabetes mellitus type 2 (DM2). Nevertheless, both patients and medical staff confront barriers in using this therapeutic tool. This study employs a qualitative approach to explore the barriers to early insulinization among medical staff from the public sector in the city of Xalapa, Veracruz, México. Between 2015 and 2016, in-depth interviews were conducted with general and specialist physicians offering primary health care to patients with DM2. The transcribed interviews were analyzed to extract and organize categories and subcategories of barriers among medical staff. These barriers were then grouped into three categories and exemplified with interview excerpts: barriers coming from the medical staff itself, barriers emerging from the doctor-patient interaction, and institutional barriers. Uses for the classification obtained are discussed, as are some of the solutions proposed by study participants.

Adaptación y validación en población mexicana del Cuestionario de personalidad tipo C (PCTC) / Adaptation and validation of the Mexican population type C personality questionnaire (PCTC)

Resumen El objetivo de este trabajo es la adaptación y validación del Cuestionario de personalidad tipo C, elaborado por López, Ramírez y Esteve & Anarte (1998, 2002) a una población mexicana. Se realizó una adaptación lingüística del Cuestionario, y se aplicó a una muestra de 391 personas en las ciudades de Chihuahua y Xalapa, México. El análisis factorial llevó a eliminar seis de los reactivos de la escala original. El resto de los reactivos se agrupan en cuatro factores. El análisis factorial confirmatorio indica que los factores fundamentales del constructo de personalidad tipo C en población mexicana son los de comprensión, no expresión emocional y necesidad de armonía, aunque en la muestra de la ciudad de Xalapa, este último factor no fue fundamental. La confiabilidad total de la escala por el método alfa de Cronbach fue de 0.757, y en las cuatro subescalas osciló entre 0.645 y 0.842.

Abstract The aim of this work was the adaptation and validation of the Type-C Personality scale C, by Lopez, Ramirez and Esteve & Anarte (1998, 2002). Linguistic adaptation of the questionnaire was carried out with a sample of 391 people in the cities of Chihuahua and Xalapa, México. Factor analysis led to eliminate six items from the original scale. The remaining items were grouped in four factors. Confirmatory factor analysis indicates that the fundamental factors of type C personality construct are understanding, emotional inexpressiveness, and need for harmony. Nevertheless, need for harmony was not fundamental in the sample from Xalapa. The overall reliability (Cronbach's alpha) of the scale was 757 and for the four subscales ranged from 0.645 to 0.842.

[Why don't doctors use early insulinization therapy in patients with diabetes mellitus type 2?: A qualitative approach in a Mexican city]. / ¿Por qué los médicos no utilizan en forma temprana la insulinización en pacientes con diabetes mellitus tipo 2?: Un estudio cualitativo en una ciudad mexicana.

Early insulinization therapy is regarded as an efficient aid to improve long term control and quality of life in patients with diabetes mellitus type 2 (DM2). Nevertheless, both patients and medical staff confront barriers in using this therapeutic tool. This study employs a qualitative approach to explore the barriers to early insulinization among medical staff from the public sector in the city of Xalapa, Veracruz, México. Between 2015 and 2016, in-depth interviews were conducted with general and specialist physicians offering primary health care to patients with DM2. The transcribed interviews were analyzed to extract and organize categories and subcategories of barriers among medical staff. These barriers were then grouped into three categories and exemplified with interview excerpts: barriers coming from the medical staff itself, barriers emerging from the doctor-patient interaction, and institutional barriers. Uses for the classification obtained are discussed, as are some of the solutions proposed by study participants.

La terapia de insulinización temprana ha demostrado ser un auxilio eficaz para mejorar el control a largo plazo y la calidad de vida de pacientes con diabetes mellitus tipo 2. Sin embargo, tanto los pacientes como los médicos presentan barreras al uso de esta alternativa terapéutica. El presente estudio utiliza un abordaje cualitativo para explorar las barreras a la insulinización temprana que tiene el personal médico del sector público en la ciudad de Xalapa, Veracruz, México. Entre los años 2015 y 2016, se realizaron entrevistas en profundidad a médicos generales y especialistas que brindaban atención primaria a pacientes con diabetes mellitus tipo 2. Las entrevistas transcritas fueron analizadas para extraer y esquematizar las categorías y subcategorías de las barreras del personal de salud, las cuales se agruparon en tres categorías que fueron ejemplificadas con extractos del discurso de los participantes: barreras propias del personal médico, barreras que surgen en la relación médico-paciente, y obstáculos institucionales. Se discuten los posibles usos del esquema obtenido, así como algunas propuestas de solución generadas por los participantes del estudio.

Percepción de cualidades restauradoras de los espacios escolares de bachillerato en la ciudad de Xalapa, México / Perceived restorativeness in school spaces of high schools in Xalapa City, México / Percepção de qualidades restauradoras dos espaços escolares de ensino médio na cidade de Xalapa, México

El presente estudio se llevó a cabo con estudiantes de centros educativos de nivel bachillerato en Xalapa, México, y tuvo el objetivo de identificar y comparar las cualidades restauradoras percibidas en sus espacios escolares de acuerdo con la Teoría de la Restauración de la Atención. Se trabajó con una muestra no probabilística de 706 estudiantes de siete bachilleratos. Se recopilaron datos mediante una encuesta sociodemográfica y la Escala del Potencial Restaurador de los Espacios Escolares (EPREE).Los resultados mostraron que las áreas verdes de las escuelas eran los espacios de descanso con mayores cualidades restauradoras, y que los lugares de descanso favoritos poseían más cualidades restauradoras que los no favoritos. Los alumnos varones, los de más edad y aquellos cuya madre (jefe de familia) tenía niveles inferiores de estudios reportaron una percepción más positiva de los espacios escolares. Las escuelas más grandes y con áreas verdes fueron mejor valoradas en las dimensiones de fascinación, posibilidad de estar alejado, y extensión. Los resultados confirmaron las propuestas centrales de la teoría de la restauración de la atención en el contexto de los espacios escolares.

The present study was carried out with high school students from Xalapa, Mexico. Its aim was to identify and compare the perceived restorativeness in their school environments according to the attention restoration theory. This work is based on a non-probabilistic sample of 706 students from seven high schools. All data were compiled by a sociodemographic survey and the Scale of the Restorative Potential of School Spaces (EPREE, for its the Spanish acronym). The results proved that green areas were the rest spaces with major restorative qualities and that the students' favorite rest places possessed more restorative qualities than other places. Males, older pupils and those whose mother (head of the family) had a lower educational level reported a more positive perception of the school spaces. The largest schools with green areas obtained a higher evaluation for their dimensions of fascination, being away and extent. The results confirmed the main propositions of the attention restoration theory.

Este artigo foi realizado com estudantes de centros educativos de ensino médio em Xalapa (México) e teve como objetivo identificar e comparar as qualidades restauradoras percebidas em seus espaços escolares de acordo com a Teoria da Restauração da Atenção. Trabalhou-se com uma amostra não probabilística de 706 estudantes de sete turmas de ensino médio. Coletaramse dados mediante uma enquete sociodemográfica e a Escala do Potencial Restaurador dos Espaços Escolares (EPREE). Os resultados mostraram que as áreas verdes dos centros eram os espaços de descanso com maiores qualidades restauradoras e que os lugares de descanso preferidos pelos estudantes possuíam mais qualidades restauradoras do que os não preferidos. Os estudantes do gênero masculino, os de mais idade e aqueles cuja mãe (cabeça de família) tinha níveis inferiores de escolaridade relataram uma percepção mais positiva dos espaços escolares. Os maiores centros e com áreas verdes tiveram melhores avaliações nas dimensões de fascinação, possibilidade de estar isolado e extensão. Os resultados confirmaram as propostas centrais da Teoria da Restauração da Atenção no contexto dos espaços escolares.

[Design and validation of a scale to assess self-regulation of eating habits in Mexican university students]. / Diseño y validación de una escala para valorar la autorregulación de hábitos alimentarios en estudiantes universitarios mexicanos.

Healthy eating habits promote wellness and prevent disease, however, despite the intention to change a bad habit, people often fail in theirattempts. This is due, since the performance of a change requires self-regulation skills that allow to observe, to evaluate and to take an action, in a constant motivation during the all the process; not only theknowledge about proper nutrition. The objective of this study was to design and validate an instrument to evaluate the level of self-regulation for eating habits in college students.62 items were written and evaluated by four expert judges. Two applications of the instrument were performed to 487 subjects. An unweighted least squares factor analysis whit direct Oblimin rotation was performed. The items saturated in more than one factor were discarded, as well as those who had a loading factor less than 0.40 or commonality less than 0.30. It was obtained an instrument integrated by 14 items grouped into three factors, which explained the 46.9% of the variance: self-reaction, self-observation and self-evaluation. Cronbach's alpha yielded a high reliability coefficient (α = 0.874).The results show that the scale is a valid and reliable tool to measure of self-regulation of eating habits in college students. Its applications include the diagnostic of a population and the evaluation of interventions aimed to improving nutrition based on the assumption that the processes of change require sustained self-regulation skills in people protective effect against increases in both systolic and diastolic blood pressure.

Escala de evaluación de la conducta ética del personal de enfermería en el cuidado de los pacientes / A Scale to Assess the Ethical Conduct of Nurses in Patient Care / Escala de avaliação da conduta ética do pessoal de enfermagem no cuidado dos pacientes

El presente trabajo tiene el propósito de construir una escala de evaluación de la conducta ética del personal de enfermería en el cuidado de los pacientes basada en las tres premisas fundamentales de la teoría del cuidado de Jean Watson. La versión final del cuestionario consta de 13 reactivos tipo Likert que reflejan los contenidos de las premisas fundamentales de la mencionada teoría. La validez del cuestionario se determinó por medio del análisis factorial con extracción de componentes principales y rotación varimax. Del análisis surgieron cuatro factores que explican el 64% de la varianza. Tres de los factores corresponden a las premisas fundamentales de la teoría, mientras que el cuarto factor está relacionado con la comunicación y la empatía. La adecuación de la muestra para el análisis factorial se confirmó mediante el cociente de Kaiser-Meyer-Olkin (KMO = 0,848), la prueba de esfericidad de Bartlett (p < 0,001) y el cálculo de la determinante de la matriz de correlaciones (0,006). La contabilidad por consistencia interna de la escala global es alta (a = 0,85). Se concluye que el instrumento es válido, confiable, y representa un medio conveniente para evaluar el comportamiento ético del personal de enfermería al proporcionar cuidado al paciente hospitalizado.

The purpose of this paper is to construct a scale to evaluate ethical conduct in nursing care, based on the three fundamental premises of Jean Watson's caring theory. The final version of the questionnaire consists of 13 Likert-type response categories that reflect the contents of the basic assumptions of that theory. The validity of the questionnaire was determined through factor analysis with principal component extraction and varimax rotation. The analysis suggested four factors that explain 64% of the variance. Three of the factors pertain to the basic premises of the theory, while the fourth is related to communication and empathy. Sampling adequacy for factor analysis was confirmed by means of the Kaiser-Meyer-Olkin coefficient (KMO = 0.848), Bartlett's test of sphericity (p <0.001) and calculation of the determinant of the correlation matrix (0.006). The internal consistency reliability of the overall scale is high (OC= 0.85). It was concluded the instrument is valid, reliable and represents a convenient way to assess the ethical behavior of nurses when providing care to hospitalized patients.

O presente trabalho tem o propósito de construir uma escala de avaliação da conduta ética do pessoal de enfermagem no cuidado dos pacientes baseada nas três premissas fundamentais da teoria do cuidado de Jean Watson. A versão final do questionário consta de 13 reativos tipo Likert que refletem os conteúdos das premissas fundamentais da mencionada teoria. A validade do questionário se determinou por meio da análise fatorial com extração de componentes principais e rotação varimax. Da análise surgiram quatro fatores que explicam 64% da variação. Três dos fatores correspondem às premissas fundamentais da teoria, enquanto o quarto fator está relacionado com a comunicação e a empatia. A adequação da amostra para a análise fatorial se confirmou mediante o cociente de Kaiser-Meyer-Olkin (KMO = 0,848), a prova de esfericidade de Bartlett (p < 0,001) e o cálculo da determinante da matriz de correlações (0,006). A confiabilidade por consistência interna da escala global é alta (OC= 0,85). Conclui-se que o instrumento é válido, confiável e representa um meio conveniente para avaliar o comportamento ético do pessoal de enfermagem ao proporcionar cuidado ao paciente hospitalizado.

Functional coupling between motor and sensory nerves through contraction of sphincters in the pudendal area of the female cat.

The question of whether skin receptors might help in the perception of muscle contraction and body movement has not been settled. The present study gives direct evidence of skin receptor firing in close coincidence with the contraction of the vaginal and anal sphincters. The distal stump of the sectioned motor pudendal nerve was stimulated. Single shocks induced a wavelike increase in the lumen pressure of the distal vagina and the anal canal, as well as constriction of the vaginal introitus and the anus. The constriction pulls on and moves the surrounding skin, which was initially detected visually. In the present experiments, a thin strain gauge that pressed on the skin surface detected its displacement. Single shocks to the motor nerve induced a wave of skin movement with maximal amplitude at 5 mm from the anus and propagated with decrement beyond 35 mm. The peripheral terminals of the sensory pudendal nerve and the posterior femoral nerve supply the skin that moves. Sensory axons from both nerves fired in response to both tactile stimulation and the skin movement produced by the constriction of the orifices (motor-sensory coupling). In cats with all nerves intact, a single shock to the sensory nerves induced reflex waves of skin movement and lumen pressure (sensory-motor coupling). Both couplings provide evidence for a feedforward action that might help to maintain the female posture during mating and to the perception of muscle contraction.

Structure, innervation, mechanical properties and reflex activation of a striated sphincter in the vestibule of the cat vagina.

Vaginal constriction might be important for reproduction in mammals, but existing information is both limited and controversial. This paper shows the structure, mechanical properties, innervation and reflex response of a striated sphincter in the vestibule of the cat vagina. A Foley catheter coupled to a pressure transducer detected in the lumen of the vestibule a pressure wave that was induced by stimulation of the external branch of the motor pudendal nerve. The peak pressure of the wave induced by bilateral stimulation (30.6 cm H(2)O) was about double of the peak pressure wave induced unilaterally. The tetanus/twitch amplitude ratio was 4.5. The sphincter that produces the increase in vaginal pressure fatigues slowly. Digital, point-to-point summation of unilateral waves was greater than the wave induced bilaterally. Summation of the pressure wave induced by the separate stimulation of the terminal motor branches was also greater than the wave induced by the entire motor nerve. This might reflect multiple innervation of muscle fibres. Single, controlled probing of the vaginal vestibule induced a reflex discharge in the motor nerve. Repetitive probing (10 Hz) induced a motor nerve post-discharge lasting >1 min. The vaginal sphincter is two-half rings of striated muscle fibres in the wall of the vaginal vestibule; the fibres end freely in the dorsal and ventral midlines. Penetration of the vestibule by the penis might trigger sustained contraction of the vaginal sphincter.