Antibacterial activity of silver nanoparticles against field and reference strains of Mycobacterium tuberculosis, Mycobacterium bovis and multiple-drug-resistant tuberculosis strains.

Tuberculosis (TB) is an endemic disease in animals and humans in Egypt. This study aims to investigate the antimycobacterial activity of silver nanoparticles(AgNPs) by determining the minimal inhibitory concentration (MIC) of AgNPs, using the microplate Alamar blue assay. The AgNPs were chemically synthesised and their form and size were characterised by ultraviolet-visible absorption spectrophotometry, transmission electron microscopy and X-ray diffraction.The reference strains of Mycobacterium bovis and Mycobacterium tuberculosisH37Rv, and one multiple-drug-resistant (MDR) strain of M. tuberculosis were tested, as well as clinical isolates of M. bovis and M. tuberculosis. The AgNPs were tetrahydral with a few spherical particles and an average particle size of 50 nm. The mycobacterial strains were varied with MICs of AgNPs. Both reference strains of M. tuberculosis and M. bovis, in addition to the MDR strain of M. tuberculosis, were successfully inhibited by AgNPs at MICs of 1 ?g/ml, 4 ?g/ml and 16 ?g/ml, respectively, whereas clinical isolates of M. bovis and M. tuberculosis were inhibited at MIC values of 4-32 ?g/ml and 1-16 ?g/ml, respectively. The AgNPs showed an in vitro chemotherapeutic effect against Mycobacterium spp.Thus, they can be used to treat TB not only in humans but also in animals, and maybe useful in TB prevention and control strategies worldwide.

En Egypte, la tuberculose est une maladie endémique chez l'homme comme chez l'animal. Les auteurs présentent les résultats d'une étude conduite pour mesurer l'activité antibactérienne des nanoparticules d'argent (NPAg) en déterminant les valeurs de concentration minimale inhibitrice (CMI) des NPAg au moyen du test au bleu Alamar sur microplaques. Les NPAg ont été synthétisées par une méthode chimique et leur forme et taille ont été caractérisées par spectrophotométrie d'absorption dans l'ultra-violet, microscopie électronique à transmission et diffraction des rayons X. L'étude a cible les souches de référence de Mycobacterium bovis et de Mycobacterium tuberculosis H37Rv, ainsi qu'une souche multirésistante de M. tuberculosis et des isolats cliniques de M. bovis et M. tuberculosis. Les NPAg étaient à structure tétraédrique avec quelques particules sphériques ; la taille moyenne des particules etait de 50 nm.La CMI des NPAg variait en fonction des souches. L'inhibition des deux souches de reference de M. tuberculosis et M. bovis et de la souche multirésistante de M. tuberculosis était obtenue avec des CMI de NPAg de 1 ?g/ml, 4 ?g/ml et16 ?g/ml, respectivement, tandis que les isolats cliniques de M. bovis et de M. tuberculosis étaient inhibés en présence de NPAg à des CMI comprises entre 4 et 32 ?g/ml et 1­16 ?g/ml, respectivement. L'efficacité chimiothérapeutique des NPAg contre Mycobacterium spp. a été démontrée in vitro. Ces nanoparticules peuvent donc servir à traiter la tuberculose non seulement chez l'homme mais également chez les animaux et contribuer ainsi aux stratégies de prévention et de lutte contre la tuberculose dans le monde.

En Egipto, la tuberculosis es una enfermedad endemica que afecta a personas y animales. Los autores describen un estudio encaminado a analizar la actividad antimicobacteriana de las nanoparticulas de plata, determinando para ello la concentracion inhibitoria minima de nanoparticulas mediante el ensayo de microtitulacion en placa con azul Alamar. Tras sintetizar quimicamente las nanoparticulas de plata y caracterizar su forma y tamano por espectrometria de absorcion ultravioleta-visible, microscopia electronica de transmision y difraccion de rayos X, se sometieron a prueba las cepas de referencia de Mycobacterium bovis y Mycobacterium tuberculosis H37Rv, asi como una cepa multirresistente de M. tuberculosis y muestras de M. bovis y M. tuberculosis aisladas a partir de casos clinicos. Salvo unas pocas de forma esferica, las nanoparticulas de plataeran tetraedricas. Su tamano era en promedio de 50 nm. Tras someter las cepas de micobacterias a distintas concentraciones de nanoparticulas, se observo que estas inhibian el crecimiento de las cepas de referencia de M. tuberculosis y M. bovis y de la cepa multirresistente de M. tuberculosis a concentraciones minimas de 1 ?g/ml, 4 ?g/ml y 16 ?g/ml, respectivamente, mientras que las muestras clinicas de M. bovis y M. tuberculosis quedaban inhibidas por la presencia de nanoparticulas a valores de concentracion minima de 4­32 ?g/ml y 1­16 ?g/ml, respectivamente. Tambien se observo que, in vitro, las nanoparticulas de plata mostraban actividad farmacologica contra Mycobacterium spp. De ahi se sigue que pueden ser empleadas para tratar la tuberculosis no solo en personas, sino tambien en animales, y que pueden resultar utiles en todo el mundo para las estrategias de prevencion y control de la tuberculosis.

Individuals with a Rh-positive but not Rh-negative blood group are more vulnerable to SARS-CoV-2 infection: demographics and trend study on COVID-19 cases in Sudan.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In Sudan, several haematological studies were conducted to study the ABO blood group distribution among the population, in which the O blood group was dominant followed by the A blood group. However, there is no systematic study into any correlation between COVID-19 and the population's blood group types, therefore we have intended to study the possible effect of blood group on the acquisition of SARS-CoV-2 infection. A questionnaire-based case-control study was carried out on 557 individuals with COVID-19 in Sudan; factors such as age, blood group, previous malaria infection, history of ailments such as diabetes, hypertension and symptoms suffered were also considered and analysed. More women were infected than men, and individuals between 25 and 35 years were the most affected age group. O Rhesus-positive (O+) blood group was the least affected by the disease while A Rhesus-positive (A+) individuals were the most vulnerable. Fatigue, fever and loss of smell were the major symptoms among the patients, but 13% of SARS-COV-2-positive individuals remained asymptomatic. As the Sudan population is largely constituted of O Rhesus-positive inhabitants (approximately 50%) these results might explain the relatively lower COVID-19 incidence in the country.

Nucleus accumbens opioid signaling conditions short-term flavor preferences.

Opioid signaling in the nucleus accumbens (NAcc) strongly modulates flavor-based food choice. To further investigate the role of opioid signaling in taste reward, we used a sensory specific satiety (SSS) paradigm to devalue specific flavors of nutritionally identical food pellets in rats. In the NAcc, infusion of a mu opioid (MOP) receptor selective agonist selectively increased consumption of a pre-fed flavor, thus reversing the SSS effect. Conversely, blockade of endogenous opioid signaling with the opioid antagonist naltrexone selectively decreased consumption of a recently consumed flavor, potentiating the SSS effect. No enhancement of consumption was observed if a delay of 3 h was imposed following the intra-NAcc MOP agonist indicating that there were no long-term changes in flavor preference. If a delay was introduced between the initial flavor exposure and the intra-NAcc MOP agonist infusion, pellet consumption was increased non-selectively (irrespective of flavor) suggesting that close temporal contiguity between flavor experience and NAcc opioid action is critical for the opioid effect on flavor preference. In contrast to opioid effects, inactivating NAcc neurons by local microinjection of muscimol (a GABAA agonist) increased consumption of both the pre-fed and non-pre-fed flavors equally. These results demonstrate that opioids released in the NAcc during consumption of palatable foods produce a selective and transient increase in preference for a recently sampled flavor.

Nucleus accumbens dopamine release is necessary and sufficient to promote the behavioral response to reward-predictive cues.

The nucleus accumbens is part of the neural circuit that controls reward-seeking in response to reward-predictive cues. Dopamine release in the accumbens is essential for the normal functioning of this circuit. Previous studies have shown that injection of dopamine receptor antagonists into the accumbens severely impairs an animal's ability to perform operant behaviors specified by predictive cues. Furthermore, excitations and inhibitions of accumbens neurons evoked by such cues are abolished by inactivation of the ventral tegmental area, the major dopaminergic input to the accumbens. These results indicate that dopamine is necessary to elicit neural activity in the accumbens that drives the behavioral response to cues. Here we show that accumbens dopamine release is causal to the rats' reward-seeking behavioral response by demonstrating that dopamine in this structure is both necessary and sufficient to promote the appropriate behavioral response to reward-predictive cues.

The pattern of severe protein-calorie malnutrition in Sudanese children attending a large hospital in The Sudan.

One hundred fifty patients suffering from severe protein-calorie malnutrition, admitted in 1 month to the Pediatric wards of Wad Medani Hospital, Sudan, were classified according to the Wellcome classification. Marasmus was the prevailing type. It was common in the 2nd year of life, while kwashiorkor occurred mainly under the age of 12 months. Anthropometric measurements showed that kwashiorkor was an acute disease while marasmus and marasmic kwashiorkor were more chronic. The triceps skinfold was unexpectedly low in kwashiorkor. Of the simple measurements and ratios used for assessing the nutritional status, the head/chest ratio applied ot children over 1 year was not found to be reliable and the weight for head circumference correlated poorly with deficits in other variables. Non of the major clinical features was found to be pathognomonic of any type of severe protein-calorie malnutrition. Megaloblastic anemia was common.

Male pseudohermaphroditism: factors determining the gender of rearing in Saudi Arabia.

OBJECTIVE: Experience with male pseudohermaphrodites at King Fahd Hospital of King Faisal University, Al-Khobar, Saudi Arabia from 1981 to 1991 was reviewed to ascertain the factors determining the gender of rearing. METHODS: The records of 14 patients consisting of 6 prepubertal and 8 postpubertal patients were studied. None of the patients had any prior evaluation or treatment, since their gender assignment at birth was carried out by midwives in rural communities. The males presented to our hospital with ambiguous genitalia: small phallus, bifid scrotum, perineoscrotal hypospadias, and undescended testes (UDT). Most of those raised as females presented in the postpubertal period seeking remedy for deep voice, excessive musculature, facial hair, erection of the phallus, ejaculation, inappropriate attraction to the female sex, and primary amenorrhea. As their male genotype became determined, all the patients and/or their parents, with the exception of one, insisted on appropriate reconstructive surgery to the male gender. This report focuses primarily on 11 patients assigned a female gender at birth, 10 of whom insisted on a gender change. RESULTS: Most adolescents and adults still complained of small penises after reconstructive surgery, but cherished their male role. CONCLUSIONS: The male genotype is a more important factor than phallic adequacy in determining the gender of rearing in the Kingdom of Saudi Arabia, an observation attributable to the financial, social, and cultural benefits that the male gender confers in Saudi society.

Epidemiology of accidental home poisoning in Riyadh (Saudi Arabia).

In a prospective study on 178 cases of accidental home poisoning admitted to the main children's hospital in Riyadh poisoning was found to account for 5.6% of the total annual admissions--greater than any other developing country and approaching Western proportions. The commonest ages were between 1 and 5 years. Drugs accounted for 52% of cases and household products for 46%. This picture also differs from the pattern of poisoning in developing countries and is more akin to that of industrialised countries. The most important factors in aetiology, besides the age of the patient and the underprivileged social class, were the abundance of drugs and household chemicals in the Saudi home, none of them in child proof containers; inappropriate storage; and lack of supervision of children. Cultural factors also contributed. The frequency of poisoning in childhood may be decreased in the long run by improved housing, socioeconomic status, and education. The place and methods of health education, also a long term objective, is discussed. For immediate primary prevention two important legislative measures are proposed: (1) provision of childproof containers of drugs and other chemicals used in the home and (2) banning of over the counter sales of drugs. For more accurate epidemiological data collection, and thereby better preventative planning, a national register of accidental poisoning and other accidents is recommended. Poison information centres are also deemed necessary.

Seroepidemiology of rubella in Saudi Arabia: an adapted vaccination policy.

Rubella haemagglutination antibodies were tested for in sera of 1793 unvaccinated subjects with age ranging from birth to 40 years. This was to assess the immune status of the population and to see the feasibility of introduction and the proper age for rubella vaccination in a Saudi community. Those with titres of greater than or equal to 1:8 were considered as seropositive. The lowest level of antibodies was seen among the 10-18 month age group. All children aged 2-5 years were seropositive as were 75% of the elementary school girls. Only 90-95% of the women of childbearing age were seropositive, however, leaving an immune gap of 5-10%. Unnecessary mass vaccination of young children is discouraged. Rubella vaccine should be given to all final elementary school girls and all women of childbearing age after screening, whenever possible. Special catchment zones are suggested for the latter group. Further nationwide seroepidemiological surveys are recommended for the other parts of the Saudi Kingdom.

The comprehensive child health care centres in the Sudan.

In 1963, Morley initiated the concept of clinics for children under five years old. This paper describes our experience in applying that concept in Omdurman town (Sudan) where existing maternity and child health centres and hospitals in the area were involved in the scheme. It was found necessary to establish a main centre to develop methodology and to provide a specialized training of staff. The medical problems were similar to those described by Morley. The approach to their solution was essentially the same except that we used more professional staff and placed more emphasis on nutrition education than hitherto advocated. It is concluded that, in theory, Morley's concept provides a system of comprehensive child health care which suits the needs of developing countries. But our adaptation of Morley's ideas to existing health structures, even on the small scale we achieved in Omdurman, was difficult because of the high initial and running costs and in view of the long established dichotomy between curative and preventive medicine.

Datura intoxication in Riyadh.

Cases of stramonium poisoning due to deliberate abuse by young adults have been widely reported. There are also a few reports of accidental poisoning in children from contaminated food. The taste and shape of Datura stramonium makes it unattractive to both man and animals and, therefore, ingestion by children in ignorance of its toxicity is rare. Three such cases are described in this paper. In Saudi Arabia stramonium abuse is unheard of and poisoning of children as a result of food contamination is very unlikely. Cases of ingestion in ignorance are, however, likely to occur frequently since D. stramonium grows in many parts of the country. The doses taken under the circumstances, though toxic, were small. The patients, therefore, suffered mainly the peripheral signs of the anti-cholinergic action of atropine, the principal D. stramonium alkaloid. Central nervous system manifestations and toxic psychosis were minimal in contrast to intentional misuse or accidental poisoning. Due to the special susceptibility of children to atropine toxicity and the relatively small lethal dose (less than or equal to 10 mg), treatment with the specific antidote, physostigmine salicylate, is emphasized for all but the mildest cases, in addition to any symptomatic treatment that might be needed.

Effect of ambrein on blood glucose levels of rats.

Ambrein reduced the blood glucose level of normal and moderately alloxan-diabetic rats but did not reduce the blood glucose levels of severely-diabetic rats. Ambrein did not reduce the hyperglycemia of glucose-loaded rats also given mannoheptulose but it reduced the hyperglycemia of glucose-loaded rats in the absence of mannoheptulose. Results suggested that the hypoglycemic activity of ambrein may be mediated by enhanced glucose utilization.

Protection by epicoprostanol against hyperglycemia and insulitis in normal and diabetic rats.

Epicoprostanol (3-alpha-hydroxy-5 beta-cholestanol) has been studied for its effects on blood glucose and plasma insulin levels in rodents. Epicoprostanol significantly induced hypoglycemia and increased insulin levels in rat blood plasma by 88% and 66% compared to that of control after 2 h and 4 h of acute treatment at 100 mg/kg dose. It also highly significantly lowered blood glucose levels in a dose dependent manner at 50, 100 and 200 mg/kg doses when administered to alloxan-rendered moderately diabetic rats after 120 and 240 min of treatment. Similarly, epicoprostanol, with the same dosage regimen, caused hypoglycemia in streptozotocin-induced severe diabetic rats, to a similar extent at the same time-points. However, the lowest dose (10 mg/kg) failed to produce a striking effect in either of the diabetic groups. In normoglycemic rats, plasma insulin levels were affected significantly after a single dose (100 mg/kg) of epicoprostanol. In contrast, diabetic animals suffering from insulitis showed a significant decline in hyperglycemia, strongly suggesting an insulin-like action of epicoprostanol. It seems likely that epicoprostanol acts through a mechanism other than hyperinsulinemia.

Effect of ambrein on smooth muscle responses to various agonists.

The pharmacological effects of ambrein (isolated from ambergris) on the contractile responses induced by some agonists in smooth muscle preparations were investigated. Ambrein in the concentration range of 10, 50 and 250 microg/ml decreased the spontaneous contraction of the isolated rabbit jejunum, rat uterus and guinea-pig vas deferens. Ambrein-induced antagonism to acetylcholine (Ach) in the guinea-pig ileum was abolished when the concentration of calcium chloride in the Tyrode's solution was increased to 5 mM/l. Furthermore, ambrein did not antagonise nicotine-induced contractions in the isolated rabbit jejunum or serotonin-induced contractions in the isolated guinea-pig ileum and vas deferens or the rat uterus. However, ambrein in the concentration range of 10, 50 and 250 microg/ml antagonised prostaglandins (PGs) E2, D2, F2alpha, and oxytocin-induced contractions in the rat uterus in vitro. Ambrein also antagonised (+/-) noradrenaline and (-) adrenaline-induced contractions in the isolated guinea-pig vas deferens. It is concluded that ambrein-induced non-selective dose-dependent antagonism to the effects of some agonists (Ach, adrenaline, noradrenaline, PGs and oxytocin) in some smooth muscles may be due to the ability of this compound to interfere with the mobilisation of extracellular Ca2+ required for muscular contractions induced by these agonists.

Management of an unusually high postpubertal presentation of cryptorchidism.

A high proportion (43%) of postpubertal presentation of cryptorchid testes was found in 114 patients with undescended testes (UDT). Bilateral presentation of UDT was observed in 25% of patients. Orchiopexy was performed on 75% of postpubertal cases, the determinant factor for choice of operation being cosmetic and psychological. Follow-up results appear to be promising in this environment with very low incidence of testicular cancer.

Fracture of the penis: surgical management.

Fracture of the penis is a rare injury, only 135 patients having been reported by 1985. Our recent experience with six patients who underwent emergency surgery, has been documented. The results of treatment were excellent with complete recovery of function. The study recommends operative management as the treatment of choice.

Risk factors in wound infection following urologic operations: a prospective study.

A total of 134 urologic operations were studied prospectively for postoperative wound infection, the methodology involving direct intraoperative swab taking. Patients' variables were (mean +/- SD): age 32.4 +/- 20.7 years, Quetelet index 27.4 +/- 8, duration of operation 98 +/- 34 minutes, and male:female ratio 9.3:1. Of the 131 intraoperative swabs 28 (21%) were positive, 97% of the organisms being aerobic; 16% of the patients were nasal carriers of S. aureus. The overall wound infection rate was 9%, and it prolonged hospital stay by six days average. Significant risk factors (and their magnitude) were: age over 60 years (x 2.2), prolonged preoperative hospital stay (x 15), and wound contamination (x 4.3 and x 14.3 for classes 3 and 4 wounds respectively). Neither diabetes mellitus, obesity, nor surgeon's rank was contributory. We conclude that, although the 9% rate of postoperative wound infection was acceptable, appropriate prophylactic antibiotics may reduce it further, and, from our data, we would recommend an aminoglycoside (e.g. Amikacin) and Ampicillin combined.

Unusual high presentation of torsion of testicular appendages.

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Anterior hypospadias. Is repair necessary with urination in a sitting or squatting position?

OBJECTIVE: To determine the chronic complication rate of anterior hypospadias repair and to explore whether the practice of placing the neomeatus at the tip of the penis should be applicable to all cases in our community where urination is in a sitting/squatting position. METHODS: Over a 10-year period commencing 1st September 1987, 312 patients had hypospadias repair of whom 72% had anterior hypospadias. The meatus was advanced to the tip of the penis in all repairs. The location of the meatus was also determined in 281 non-complaining men with a straight penis and normal sexual and reproductive functions. Following prior information that anterior hypospadias was not associated with sexual and reproductive dysfunction, 51 patients were given a choice between repair or no repair. RESULTS: Urethrocutaneous fistula occurred in 5% of patients, urethral stricture in 3% and meatal retraction in 3%, with 92% of patients having no complications. Forty six percent of non-complaining men had the meatus in locations other than the tip of the penis. Of 51 patients with the benefit of informed consent, 73% opted for no repair. CONCLUSION: Our results of anterior hypospadias repair compare favourably with those of other centers. Placement of the meatus at the tip of the penis for anterior hypospadias should not be applicable to all patients in this community where urination is in a sitting/squatting position. Before such repairs, an informed consent is warranted by making the patients and their parents aware of the non-association of sexual and reproductive disorders with these anomalies.

Physicians' knowledge, attitude and practice towards erectile dysfunction in Saudi Arabia.

We aimed to test the knowledge, attitude and practice (KAP) of physicians towards erectile dysfunction in the Eastern province of Saudi Arabia. At a scientific meeting about erectile dysfunction, 159 physicians from both government and private sectors answered a 34-item questionnaire in private. The mean total KAP score for the group was below the expected standard of 60%. Male physicians scored significantly higher than females. Urologists scored the highest, followed by andrologists. Surprisingly, physicians with higher qualifications scored lower than those with intermediate qualifications and even less than general practitioners. Those who had practised for > or = 10 years scored better than those with < 10 years practice. The role of cardiologists in the diagnosis and management of erectile dysfunction is discussed.

Rectus andominis myocutaneous flap: Analysis of 40 cases.

We present a series of 40 cases who underwent reconstructive procedures using rectus abdominis myocutaneous units. The transplanted tissue comprised superior pedicle (26 cases), inferior pedicle (11 cases), and as free muscle flap (3 cases). The application fell into three groups i.e.; 1. breast and chest wall reconstruction; 2. groin, genital, and trochanteric area; and 3. leg and heel ulcer. The results show that surgical dissection of flaps is relatively easy and has a wide range of applications that can be used for different surgical reconstructive problems. Surgical dissection has a low incidence of complication for flap viability as well as for donor site.