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1.
Exp Physiol ; 108(2): 280-295, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36459572

RESUMEN

NEW FINDINGS: What is the central question of this study? What are the effects of insulin and insulin-induced hypoglycaemia on carotid body chemoreceptor activity in vivo and how do carotid body chemoreceptor stimulation-mediated cardiorespiratory responses in beagle dogs compare during euglycaemia and insulin-induced hypoglycaemia? What is the main finding and its importance? Intracarotid insulin administration leads to sustained increase in carotid body chemoreceptor activity and respiratory response with significant cardiovascular effects. Insulin-induced hypoglycaemia exacerbated NaCN-mediated carotid body chemoreceptor activity and respiratory response with enhanced cardiovascular reflex response. These findings suggest that insulin-induced hypoglycaemia augments the carotid body chemoreceptors to initiate the adaptive counter-regulatory responses to restore the normoglycaemic condition. ABSTRACT: The carotid body chemoreceptors (CBC) play an important role in the adaptive counter-regulatory response to hypoglycaemia by evoking the CBC-mediated sympathetic neuronal system to restore normoglycaemia. Ex vivo studies have shown varied responses of insulin-induced hypoglycaemia on CBC function, and several in vivo studies have indirectly established the role of CBCs in restoring normoglycaemia in both animals and humans. However, a direct effect of insulin and/or insulin-induced hypoglycaemia on CBC activity is not established in animal models. Therefore, the aim of this study was to evaluate in vivo effects of insulin and insulin-induced hypoglycaemia on CBC activity and cardiorespiration in a preclinical large animal model. The carotid sinus nerve (CSN) activity and cardiorespiratory responses to sodium cyanide (NaCN; 25 µg/kg) were compared before (euglycaemic) and after (hypoglycaemic) intracarotid administration of insulin (12.5-100 µU/dogs) in beagle dogs. Insulin administration increased CSN activity and minute ventilation ( V ̇ $\dot V$ E ) with significant (P < 0.0001) effects on heart rate and blood pressure. Insulin-mediated effects on CSN and cardiorespiration were sustained and the change in V ̇ $\dot V$ E was driven by tidal volume only. Insulin significantly (P < 0.0001) lowered blood glucose level. NaCN-mediated CSN activity and V ̇ $\dot V$ E were significantly (P < 0.0001) augmented during insulin-induced hypoglycaemia. The augmented V ̇ $\dot V$ E was primarily driven by respiratory frequency and partially by tidal volume. The cardiovascular reflex response mediated through CBC stimulation was significantly (P < 0.0001) exacerbated during insulin-induced hypoglycaemia. Collectively, these results demonstrate direct effects of insulin and insulin-induced hypoglycaemia on CBC chemosensitivity to potentiate CBC-mediated neuroregulatory pathways to initiate adaptive neuroendocrine and cardiorespiratory counter-regulatory responses to restore normoglycaemia.


Asunto(s)
Cuerpo Carotídeo , Hipoglucemia , Humanos , Perros , Animales , Cuerpo Carotídeo/metabolismo , Insulina/metabolismo , Células Quimiorreceptoras/fisiología , Reflejo , Presión Sanguínea
2.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33972441

RESUMEN

Neuromodulation of immune function by stimulating the autonomic connections to the spleen has been demonstrated in rodent models. Consequently, neuroimmune modulation has been proposed as a new therapeutic strategy for the treatment of inflammatory conditions. However, demonstration of the translation of these immunomodulatory mechanisms in anatomically and physiologically relevant models is still lacking. Additionally, translational models are required to identify stimulation parameters that can be transferred to clinical applications of bioelectronic medicines. Here, we performed neuroanatomical and functional comparison of the mouse, rat, pig, and human splenic nerve using in vivo and ex vivo preparations. The pig was identified as a more suitable model of the human splenic innervation. Using functional electrophysiology, we developed a clinically relevant marker of splenic nerve engagement through stimulation-dependent reversible reduction in local blood flow. Translation of immunomodulatory mechanisms were then assessed using pig splenocytes and two models of acute inflammation in anesthetized pigs. The pig splenic nerve was shown to locally release noradrenaline upon stimulation, which was able to modulate cytokine production by pig splenocytes. Splenic nerve stimulation was found to promote cardiovascular protection as well as cytokine modulation in a high- and a low-dose lipopolysaccharide model, respectively. Importantly, splenic nerve-induced cytokine modulation was reproduced by stimulating the efferent trunk of the cervical vagus nerve. This work demonstrates that immune responses can be modulated by stimulation of spleen-targeted autonomic nerves in translational species and identifies splenic nerve stimulation parameters and biomarkers that are directly applicable to humans due to anatomical and electrophysiological similarities.


Asunto(s)
Sistema Inmunológico/inervación , Inmunomodulación/efectos de los fármacos , Bazo/inmunología , Sistema Nervioso Simpático/inmunología , Nervio Vago/inmunología , Animales , Femenino , Expresión Génica , Humanos , Sistema Inmunológico/efectos de los fármacos , Inflamación , Interleucina-6/genética , Interleucina-6/inmunología , Lipopolisacáridos/farmacología , Ratones , Microcirculación/efectos de los fármacos , Microcirculación/genética , Microcirculación/inmunología , Norepinefrina/farmacología , Ratas , Especificidad de la Especie , Bazo/efectos de los fármacos , Bazo/inervación , Bazo/patología , Porcinos , Sistema Nervioso Simpático/efectos de los fármacos , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Nervio Vago/efectos de los fármacos , Estimulación del Nervio Vago/métodos
3.
Front Immunol ; 12: 649786, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33859641

RESUMEN

Neuromodulation of the immune system has been proposed as a novel therapeutic strategy for the treatment of inflammatory conditions. We recently demonstrated that stimulation of near-organ autonomic nerves to the spleen can be harnessed to modulate the inflammatory response in an anesthetized pig model. The development of neuromodulation therapy for the clinic requires chronic efficacy and safety testing in a large animal model. This manuscript describes the effects of longitudinal conscious splenic nerve neuromodulation in chronically-implanted pigs. Firstly, clinically-relevant stimulation parameters were refined to efficiently activate the splenic nerve while reducing changes in cardiovascular parameters. Subsequently, pigs were implanted with a circumferential cuff electrode around the splenic neurovascular bundle connected to an implantable pulse generator, using a minimally-invasive laparoscopic procedure. Tolerability of stimulation was demonstrated in freely-behaving pigs using the refined stimulation parameters. Longitudinal stimulation significantly reduced circulating tumor necrosis factor alpha levels induced by systemic endotoxemia. This effect was accompanied by reduced peripheral monocytopenia as well as a lower systemic accumulation of CD16+CD14high pro-inflammatory monocytes. Further, lipid mediator profiling analysis demonstrated an increased concentration of specialized pro-resolving mediators in peripheral plasma of stimulated animals, with a concomitant reduction of pro-inflammatory eicosanoids including prostaglandins. Terminal electrophysiological and physiological measurements and histopathological assessment demonstrated integrity of the splenic nerves up to 70 days post implantation. These chronic translational experiments demonstrate that daily splenic nerve neuromodulation, via implanted electronics and clinically-relevant stimulation parameters, is well tolerated and is able to prime the immune system toward a less inflammatory, pro-resolving phenotype.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Endotoxemia/terapia , Neuroinmunomodulación/fisiología , Nervios Esplácnicos/fisiología , Bazo/inervación , Animales , Modelos Animales de Enfermedad , Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Endotoxemia/inmunología , Femenino , Inflamación/inmunología , Inflamación/terapia , Bazo/inmunología , Sus scrofa
4.
Commun Biol ; 3(1): 577, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-33067560

RESUMEN

Neuromodulation is a new therapeutic pathway to treat inflammatory conditions by modulating the electrical signalling pattern of the autonomic connections to the spleen. However, targeting this sub-division of the nervous system presents specific challenges in translating nerve stimulation parameters. Firstly, autonomic nerves are typically embedded non-uniformly among visceral and connective tissues with complex interfacing requirements. Secondly, these nerves contain axons with populations of varying phenotypes leading to complexities for axon engagement and activation. Thirdly, clinical translational of methodologies attained using preclinical animal models are limited due to heterogeneity of the intra- and inter-species comparative anatomy and physiology. Here we demonstrate how this can be accomplished by the use of in silico modelling of target anatomy, and validation of these estimations through ex vivo human tissue electrophysiology studies. Neuroelectrical models are developed to address the challenges in translation of parameters, which provides strong input criteria for device design and dose selection prior to a first-in-human trial.


Asunto(s)
Estimulación Eléctrica , Bazo/inervación , Animales , Estimulación Eléctrica/métodos , Terapia por Estimulación Eléctrica/métodos , Fenómenos Electrofisiológicos , Humanos , Bazo/anatomía & histología , Bazo/irrigación sanguínea , Bazo/citología , Porcinos
5.
Sci Rep ; 9(1): 18136, 2019 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-31792232

RESUMEN

Recent research supports that over-activation of the carotid body plays a key role in metabolic diseases like type 2 diabetes. Supressing carotid body signalling through carotid sinus nerve (CSN) modulation may offer a therapeutic approach for treating such diseases. Here we anatomically and histologically characterised the CSN in the farm pig as a recommended path to translational medicine. We developed an acute in vivo porcine model to assess the application of kilohertz frequency alternating current (KHFAC) to the CSN of evoked chemo-afferent CSN responses. Our results demonstrate the feasibility of this approach in an acute setting, as KHFAC modulation was able to successfully, yet variably, block evoked chemo-afferent responses. The observed variability in blocking response is believed to reflect the complex and diverse anatomy of the porcine CSN, which closely resembles human anatomy, as well as the need for optimisation of electrodes and parameters for a human-sized nerve. Overall, these results demonstrate the feasibility of neuromodulation of the CSN in an anesthetised large animal model, and represent the first steps in driving KHFAC modulation towards clinical translation. Chronic recovery disease models will be required to assess safety and efficacy of this potential therapeutic modality for application in diabetes treatment.


Asunto(s)
Seno Carotídeo/inervación , Animales , Cuerpo Carotídeo/efectos de los fármacos , Cuerpo Carotídeo/fisiología , Seno Carotídeo/anatomía & histología , Seno Carotídeo/efectos de los fármacos , Electrodos Implantados , Femenino , Humanos , Conducción Nerviosa , Respiración , Cianuro de Sodio/farmacología , Porcinos
6.
Eur J Contracept Reprod Health Care ; 24(5): 390-398, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31517545

RESUMEN

Background: Multipurpose prevention technologies are needed to provide protection against HIV and sexually transmitted infections. Gel-based vaginal microbicides inserted via an applicator are prone to leakage. A novel device for vaginal drug delivery was developed to contain gel-based formulations, aiming to improve gel retention and reduce leakage. The objectives of this study were to assess acceptability and performance of a nonwoven vaginal delivery device. Methods: A nonwoven vaginal delivery device was prepared, pre-saturated with a commercially available water-based lubricant, with a finger pocket for insertion and string for removal. Quantitative and qualitative methods were used to collect data from interviews with 40 women and 10 male partners recruited from a sexual and reproductive health clinic in Durban, KwaZulu-Natal, South Africa. Women wore one device in the clinic and one device overnight or with their partner during intercourse. The primary endpoint was acceptability including comfort, ease of insertion and removal, and opinions on device attributes. Results: Most women said the device was 'easy' to insert and remove. Six women reported leakage after insertion and 34 reported having sexual intercourse while wearing the device. One woman was lost-to-follow-up and five women only wore the device overnight because their partners did not agree to intercourse with the inserted device. The best-liked attribute was the device's lubrication (22 women, 7 men); the least-liked was the removal string (9 women, 8 men). Conclusions: Data are promising for further development of this nonwoven device for vaginal drug delivery. Plain English summary Multipurpose prevention technologies (MPTs) that protect against HIV and sexually transmitted infections (STIs) are urgently needed. A variety of vaginal gel-based products are actively being researched; however, these products can often have challenges with vaginal leakage and retention. This research investigates the acceptability and performance of a nonwoven device to deliver vaginal gel formulations. The gel used in this study was a currently available marketed personal lubricant. In South Africa, 40 women (and 10 male partners) were recruited and given the opportunity to comment on various device attributes after insertion, overnight wear and sexual intercourse with their male partners. Generally, participants found the device easy to use and acceptable, where many factors possibly contributed to the device's acceptability (i.e., similarity to tampons, saturation with lubricant, minimal leakage, ease of insertion, comfort during intercourse and the male partners' willingness to have vaginal intercourse with the device in place). Further studies of the vaginal delivery device for acceptability, safety and efficacy using a gel-based formulation with an active ingredient are warranted.


Asunto(s)
Sistemas de Liberación de Medicamentos/psicología , Aceptación de la Atención de Salud/psicología , Parejas Sexuales/psicología , Enfermedades de Transmisión Sexual/prevención & control , Cremas, Espumas y Geles Vaginales/administración & dosificación , Administración Intravaginal , Adulto , Coito/psicología , Femenino , Humanos , Masculino , Investigación Cualitativa , Enfermedades de Transmisión Sexual/psicología , Sudáfrica , Resultado del Tratamiento , Adulto Joven
7.
Contraception ; 97(1): 62-69, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28887053

RESUMEN

OBJECTIVE: We modeled the potential impact of novel male contraceptive methods on averting unintended pregnancies in the United States, South Africa, and Nigeria. STUDY DESIGN: We used an established methodology for calculating the number of couple-years of protection provided by a given contraceptive method mix. We compared a "current scenario" (reflecting current use of existing methods in each country) against "future scenarios," (reflecting whether a male oral pill or a reversible vas occlusion was introduced) in order to estimate the impact on unintended pregnancies averted. Where possible, we based our assumptions on acceptability data from studies on uptake of novel male contraceptive methods. RESULTS: Assuming that only 10% of interested men would take up a novel male method and that users would comprise both switchers (from existing methods) and brand-new users of contraception, the model estimated that introducing the male pill or reversible vas occlusion would decrease unintended pregnancies by 3.5% to 5.2% in the United States, by 3.2% to 5% in South Africa, and by 30.4% to 38% in Nigeria. Alternative model scenarios are presented assuming uptake as high as 15% and as low as 5% in each location. Model results were sensitive to assumptions regarding novel method uptake and proportion of switchers vs. new users. CONCLUSION: Even under conservative assumptions, the introduction of a male pill or temporary vas occlusion could meaningfully contribute to averting unintended pregnancies in a variety of contexts, especially in settings where current use of contraception is low. IMPLICATIONS: Novel male contraceptives could play a meaningful role in averting unintended pregnancies in a variety of contexts. The potential impact is especially great in settings where current use of contraception is low and if novel methods can attract new contraceptive users.


Asunto(s)
Anticoncepción , Modelos Teóricos , Índice de Embarazo , Embarazo no Planeado , Femenino , Humanos , Masculino , Nigeria , Embarazo , Sudáfrica , Estados Unidos
8.
J Acquir Immune Defic Syndr ; 72 Suppl 1: S18-23, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27331585

RESUMEN

BACKGROUND: Men's understanding of counseling messages after voluntary medical male circumcision (VMMC) plays an important role in whether they follow them. Data on triggers for early resumption of sex may be useful as scale-up of VMMC for HIV prevention continues in sub-Saharan Africa. METHODS: Data on understanding of post-VMMC abstinence recommendations, resumption of sex, condom use, and triggers for resuming sex were collected from participants during a follow-up interview 35-42 days after ShangRing circumcision in Kenya and Zambia. RESULTS: Of 1149 men who had ShangRing circumcision, 1096 (95.4%) completed follow-up. Nearly all (99.2%) reported being counseled to abstain from sex post-VMMC; among those, most (92.2%) recalled the recommended abstinence period was 6 weeks. Most men (94.1%) reported that the counselor gave reasons for post-VMMC abstinence and recalled appropriate reasons. Few (13.4%) men reported resuming sex at 35-42 days' follow-up. Among those, 54.8% reported never using a condom post-VMMC. Younger participants (odds ratio 0.3, 95% confidence interval: 0.2 to 0.5, P < 0.0001) and those reporting at least some condom use at baseline (odds ratio 0.5, 95% confidence interval: 0.3 to 0.7, P = 0.0003) were less likely to report resuming sex. Among men who reported some condom use, most (71.5%) said condoms were much easier or easier to use after circumcision. Men reported various reasons for early resumption of sex, primarily strong sexual desire (76.4%). CONCLUSIONS: Most men reported awareness of and adherence to the counseling recommendations for post-VMMC abstinence. A minority reported early resumption of sex, and, among those, condom use was low. Results could be used to improve post-VMMC counseling.


Asunto(s)
Circuncisión Masculina/métodos , Hombres/psicología , Abstinencia Sexual/psicología , Adolescente , Adulto , Humanos , Kenia , Masculino , Persona de Mediana Edad , Zambia
11.
J Hum Lact ; 31(1): 68-75, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25412617

RESUMEN

BACKGROUND: Breastfeeding is a route of mother-to-child transmission (MTCT) of the human immunodeficiency virus (HIV). The World Health Organization recommends antiretroviral (ARV) prophylaxis as the best method to prevent mother-to-child transmission of HIV (PMTCT) during breastfeeding. The nipple shield delivery system (NSDS) is being developed as an accessible method to deliver ARVs to infants and PMTCT during breastfeeding. The NSDS can potentially circumvent hygiene and storage issues in delivering drugs to infants in low-resource settings. OBJECTIVES: The primary objective was to determine acceptability of the NSDS for PMTCT in Kenya. Secondary objectives included assessing mothers' understanding of MTCT and identifying cultural and implementation issues that might affect NSDS acceptability. METHODS: Eleven focus group discussions were conducted, each group consisting of 7 to 12 participants. Seven focus group discussions consisted of HIV-positive mothers, 2 included grandmothers/mothers-in-law, and 2 included fathers/husbands. Ten in-depth interviews were also conducted with individual maternal/child health care providers. Topics included infant feeding and HIV stigma, as well as safety, effectiveness, and feasibility of the NSDS. Device prototypes were used in discussions. RESULTS: Participants felt that the NSDS could be trusted if validated scientifically and promoted by health care professionals. HIV-related stigma, access, efficacy, and hygiene were identified as important considerations for acceptance. CONCLUSION: The NSDS is a potentially acceptable method of PMTCT during breastfeeding. Further studies are needed to confirm acceptability, safety, and efficacy. For NSDS adoption to PMTCT, strategies will need to be developed to minimize HIV-related stigma and to ensure that continuous hygiene of the device is maintained.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Lactancia Materna , Infecciones por VIH/prevención & control , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Pezones , Administración Oral , Adulto , Femenino , Grupos Focales , Humanos , Recién Nacido , Kenia , Masculino , Persona de Mediana Edad , Leche Humana , Satisfacción del Paciente
12.
J Acquir Immune Defic Syndr ; 67(4): 430-7, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25162816

RESUMEN

BACKGROUND: Circumcision devices can facilitate adult voluntary medical male circumcision programs for HIV prevention. The World Health Organization recommends field studies to confirm the safety of devices in local settings. METHODS: We evaluated the safety of the ShangRing device in routine service delivery by measuring adverse event (AE) rates overall and by HIV status. We enrolled men aged 18-54 years and scheduled them for 2 post-circumcision follow-up visits at day 7 for device removal and days 35-42. Men were examined to document AEs and healing and to ascertain client acceptability. Provider preferences were also assessed. RESULTS: We enrolled 1163 men (557 in Kenya and 606 in Zambia); the as-treated analysis population comprised 1149 men, including 84 HIV-positive men. There were no serious AEs and 2 severe AEs: 1 severe wound dehiscence and 1 severe pain, both of which resolved with treatment. There were 18 moderate/severe AEs among 16 men (1.4% of men; 95% confidence interval: 0.8% to 2.3%). The most common AE was wound dehiscence (9 men, 0.8%). Healing was similar between HIV-infected and uninfected men, with 85.7% and 87.3% completely healed at days 35-42. Most men (94.8%) were very satisfied with post-circumcision appearance of the penis, and almost all would recommend a ShangRing procedure. Nineteen of 21 providers preferred the ShangRing over conventional surgery. CONCLUSIONS: The ShangRing has an excellent safety profile with few hemorrhagic and infectious complications. The ShangRing is well accepted by clients and preferred by providers, making it a potential boon to the scale-up of adult voluntary medical male circumcision in African countries.


Asunto(s)
Circuncisión Masculina/métodos , Adolescente , Adulto , Circuncisión Masculina/efectos adversos , Circuncisión Masculina/instrumentación , Infecciones por VIH/prevención & control , Humanos , Kenia , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Cicatrización de Heridas , Adulto Joven , Zambia
13.
J Acquir Immune Defic Syndr ; 65(4): 447-55, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24583615

RESUMEN

OBJECTIVE: To compare clinical profiles of Shang Ring versus conventional circumcisions. DESIGN: Parallel group open-label randomized controlled trial with one-to-one allocations in 2 sites. METHODS: We enrolled HIV-negative men aged 18-54 years in Homa Bay, Kenya, and Lusaka, Zambia and followed them at 2, 7, 14, 21, 28, 42, and 60 days after Shang Ring versus conventional circumcision. We compared the duration of surgery, postoperative pain using a visual analog scale, adverse events rates, time to complete wound healing by clinical assessment, participant acceptability, and provider preferences between circumcision groups. RESULTS: We randomized 200 men to each group; 197 and 201 contributed to the Shang Ring and conventional surgery analyses, respectively. Adverse event rates were similar between groups. Pain scores at most time points were similar, however, the Shang Ring group reported higher scores for worst pain during erections (3.5 ± 1.9 vs. 2.3 ± 1.7; P < 0.001). Significantly more men were satisfied with the cosmetic appearance following Shang Ring male circumcision (MC), 95.7% versus 85.9% (P = 0.02) in Kenya, and 96.8% versus 71.3% (P < 0.01) in Zambia. Although median time to complete wound healing was 43 days in both groups, conventional circumcisions healed on average 5.2 days sooner (P < 0.001). Shang Ring procedures took one-third the time of conventional MC, 7 versus 20 minutes. All circumcision providers preferred the Shang Ring. CONCLUSIONS: Safety profiles of the 2 techniques were similar, all MC providers preferred the Shang Ring technique, and study participants preferred the Shang Ring's cosmetic results. The Shang Ring should be considered for adult MC as programs scale-up.


Asunto(s)
Circuncisión Masculina/efectos adversos , Circuncisión Masculina/métodos , Aceptación de la Atención de Salud/estadística & datos numéricos , Procedimientos Quirúrgicos Operativos/efectos adversos , Procedimientos Quirúrgicos Operativos/métodos , Adolescente , Adulto , Circuncisión Masculina/psicología , Estudios de Seguimiento , Humanos , Kenia , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Operativos/psicología , Adulto Joven , Zambia
15.
Obstet Gynecol ; 122(2 Pt 2): 503-505, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23884276

RESUMEN

BACKGROUND: Early infant (1-60 days of life) male circumcision is being trialed in Africa as a human immunodeficiency virus prevention strategy. Postcircumcision bleeding is particularly concerning where most infants are breastfed, and thus these infants are at increased risk of vitamin K deficiency bleeding. CASE: During a circumcision trial, one infant bled for 90 minutes postprocedure. After discovering he had not received standard prophylactic vitamin K, we gave 2 mg phytomenadione (vitamin K1) intramuscularly; bleeding stopped within 30 minutes. CONCLUSION: Vitamin K's extremely rapid action is not commonly appreciated. Neonatal vitamin K has been shown to be cost-effective. To increase availability and promote awareness of its importance, especially in low-resource settings where blood products and transfusions are limited, vitamin K should be included in the World Health Organization's Model List of Essential Medicines for Children.


Asunto(s)
Circuncisión Masculina/efectos adversos , Hemorragia/tratamiento farmacológico , Vitamina K 1/uso terapéutico , Deficiencia de Vitamina K/complicaciones , Vitaminas/uso terapéutico , África , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Recién Nacido , Masculino
16.
Antivir Ther ; 18(3): 301-10, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22914267

RESUMEN

BACKGROUND: Tenofovir gel, used vaginally before and after coitus, reduced women's acquisition of HIV by 39%. This is a safety assessment of tenofovir gel, including renal, bone, gastrointestinal, genital and haematological parameters. METHODS: In the Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004, a double-blind, randomized placebo-controlled trial, 445 of the 889 eligibly enrolled women were assigned to tenofovir gel. All participants were advised to use the gel vaginally only, with one dose of gel within 12 h before and a second dose as soon as possible after sex, with no more than two doses in 24 h. Clinical and laboratory safety data were collected at monthly and quarterly visits, respectively. Genital assessments were undertaken at enrolment and quarterly thereafter, or as indicated. RESULTS: Women assigned to tenofovir gel were exposed to an average monthly vaginal dose of 240 mg of tenofovir (six applications). In total, six women, three in each group, had mild creatinine elevations, all of which occurred in July/August 2008. The incidence of anaemia was 3.5 and 3.8 per 100 women-years in tenofovir and placebo groups, respectively (P=0.80). Of the six women (four tenofovir and two placebo) experiencing bone fractures, none were associated with abnormal phosphate or calcium values. The proportion of women with diarrhoea was higher in the tenofovir gel group (17% versus 11%; P=0.026). There was no significant increase of any genital adverse event in the tenofovir group. CONCLUSIONS: No significant renal, haematological, genital or bone effects were associated with the use of tenofovir gel. Aside from a puzzling increase in diarrhoea, tenofovir gel has an excellent safety profile.


Asunto(s)
Adenina/análogos & derivados , Fármacos Anti-VIH/efectos adversos , Antiinfecciosos Locales/efectos adversos , Organofosfonatos/efectos adversos , Adenina/administración & dosificación , Adenina/efectos adversos , Administración Intravaginal , Fármacos Anti-VIH/administración & dosificación , Antiinfecciosos Locales/administración & dosificación , Huesos/efectos de los fármacos , Femenino , Estudios de Seguimiento , Tracto Gastrointestinal/efectos de los fármacos , Infecciones por VIH/sangre , Infecciones por VIH/prevención & control , Humanos , Riñón/efectos de los fármacos , Riñón/fisiopatología , Organofosfonatos/administración & dosificación , Sudáfrica , Tenofovir , Cremas, Espumas y Geles Vaginales
17.
Contraception ; 87(3): 375-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22979953

RESUMEN

BACKGROUND: Recent developments in vasectomy research indicate that occluding the vas using cautery combined with fascial interposition (FI) significantly lowers failure rates and is an appropriate technology for low-resource settings. We report the introduction of this technique in Ministry of Health (MOH) vasectomy services in Rwanda. DESIGN: In February 2010, an international vasectomy expert trained three Rwandan physicians to become trainers in no-scalpel vasectomy (NSV) with thermal cautery and FI. The training took place over 5 days in five rural health centers. RESULTS: A total of 67 men received vasectomies (11-16 per day) and trainees successfully mastered the new occlusion technique. The MOH is now scaling up NSV with cautery and FI services nationwide. The initial cadre of trainers has subsequently trained 46 other physicians in this vasectomy technique across 27 districts of Rwanda. CONCLUSIONS: No-scalpel vasectomy with thermal cautery and FI was successfully introduced in vasectomy services in Rwanda, and a similar initiative should be evaluated in other national vasectomy services worldwide.


Asunto(s)
Vasectomía/métodos , Cauterización/instrumentación , Cauterización/métodos , Servicios de Planificación Familiar , Fasciotomía , Humanos , Masculino , Rwanda , Vasectomía/educación , Vasectomía/estadística & datos numéricos
18.
J Law Med ; 20(1): 93-123, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23156651

RESUMEN

A recent article in the JLM (Boyle GJ and Hill G, "Sub-Saharan African Randomised Clinical Trials into Male Circumcision and HIV Transmission: Methodological, Ethical and Legal Concerns" (2011) 19 JLM 316) criticises the large randomised controlled trials (RCTs) that scientists, clinicians and policy-makers worldwide have concluded provide compelling evidence in support of voluntary medical male circumcision (VMMC) as an effective HIV prevention strategy. The present article addresses the claims advanced by Boyle and Hill, demonstrating their reliance on outmoded evidence, outlier studies, and flawed statistical analyses. In the current authors' view, their claims portray misunderstandings of the design, execution and interpretation of findings from RCTs in general and of the epidemiology of HIV transmission in sub-Saharan Africa in particular. At the same time they ignore systematic reviews and meta-analyses using all available data arising from good-quality research studies, including RCTs. Denial of the evidence supporting lack of male circumcision as a major determinant of HIV epidemic patterns in sub-Saharan Africa is unsubstantiated and risks undermining the evidence-based, large-scale roll-out of VMMC for HIV prevention currently underway. The present article highlights the quality, consistency and robustness of the scientific evidence that underpins the public health recommendations, guidance, and tools on VMMC. Millions of HIV infections will be averted in the coming decades as VMMC services scale-up to meet demand, providing direct benefits for heterosexual men and indirect benefits for their female partners.


Asunto(s)
Circuncisión Masculina , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , Proyectos de Investigación , África del Sur del Sahara , Humanos , Recién Nacido , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
19.
J Urol ; 188(6 Suppl): 2482-91, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23098786

RESUMEN

PURPOSE: The purpose of this guideline is to provide guidance to clinicians who offer vasectomy services. MATERIALS AND METHODS: A systematic review of the literature using the search dates January 1949-August 2011 was conducted to identify peer-reviewed publications relevant to vasectomy. The search identified almost 2,000 titles and abstracts. Application of inclusion/exclusion criteria yielded an evidence base of 275 articles. Evidence-based practices for vasectomy were defined when evidence was available. When evidence was insufficient or absent, expert opinion-based practices were defined by Panel consensus. The Panel sought to define the minimum and necessary concepts for pre-vasectomy counseling; optimum methods for anesthesia, vas isolation, vas occlusion and post-vasectomy follow up; and rates of complications of vasectomy. This guideline was peer reviewed by 55 independent experts during the guideline development process. RESULTS: Vas isolation should be performed using a minimally-invasive vasectomy technique such as the no-scalpel vasectomy technique. Vas occlusion should be performed by any one of four techniques that are associated with occlusive failure rates consistently below 1%. These are mucosal cautery of both ends of the divided vas without ligation or clips (1) with or (2) without fascial interposition; (3) open testicular end of the divided vas with MC of abdominal end with FI and without ligation or clips; and (4) non-divisional extended electrocautery. Patients may stop using other methods of contraception when one uncentrifuged fresh semen specimen shows azoospermia or ≤ 100,000 non-motile sperm/mL. CONCLUSIONS: Vasectomy should be considered for permanent contraception much more frequently than is the current practice in the U.S. and many other nations. The full text of this guideline is available to the public at http://www.auanet.org/content/media/vasectomy.pdf.


Asunto(s)
Vasectomía/métodos , Humanos , Masculino , Cuidados Posoperatorios , Cuidados Preoperatorios , Vasectomía/normas
20.
Int J Pharm ; 434(1-2): 224-34, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22634141

RESUMEN

A new drug delivery method for infants is presented which incorporates an active pharmaceutical ingredient (API)-loaded insert into a nipple shield delivery system (NSDS). The API is released directly into milk during breastfeeding. This study investigates the feasibility of using the NSDS to deliver the microbicide sodium dodecyl sulfate (SDS), with the goal of preventing mother-to-child transmission (MTCT) of HIV during breastfeeding in low-resource settings, when there is no safer alternative for the infant but to breastfeed. SDS has been previously shown to effectively inactivate HIV in human milk. An apparatus was developed to simulate milk flow through and drug release from a NSDS. Using this apparatus milk was pulsed through a prototype device containing a non-woven fiber insert impregnated with SDS and the microbicide was rapidly released. The total SDS release from inserts ranged from 70 to 100% of the average 0.07 g load within 50 ml (the volume of a typical breastfeed). Human milk spiked with H9/HIV(IIIB) cells was also passed through the same set-up. Greater than 99% reduction of cell-associated HIV infectivity was achieved in the first 10 ml of milk. This proof of concept study demonstrates efficient drug delivery to breastfeeding infants is achievable using the NSDS.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Sistemas de Liberación de Medicamentos , Infecciones por VIH/prevención & control , Dodecil Sulfato de Sodio/administración & dosificación , Animales , Fármacos Anti-VIH/farmacología , Lactancia Materna/métodos , Bovinos , Estudios de Factibilidad , Femenino , Infecciones por VIH/transmisión , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Leche Humana/virología , Pezones , Dodecil Sulfato de Sodio/farmacología , Tensoactivos/administración & dosificación , Tensoactivos/farmacología
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