Bone mineral content for preterm neonates treated with caffeine using dual energy X-ray absorptiometry: An observational study.

BACKGROUND: Prematurity is associated with lots of comorbidities. Premature neonates also have lower bone mineral content (BMC) compared to term neonates. Apnea of prematurity is a common complication and caffeine citrate is widely used for its prevention and treatment. Caffeine also affects creatinine clearance, urine flow rate and releases calcium from its storage sites. OBJECTIVES: The primary objective was to assess BMC in preterm neonates treated with caffeine using dual energy X-ray absorptiometry (DEXA). Secondary objectives were to determine whether caffeine therapy is associated with increased incidence of nephrocalcinosis or bone fracture. METHODS: Prospective observational study on 42 preterm neonates, 34 weeks' gestation or less; 22 of them received intravenous caffeine (caffeine group) and 20 did not (control group). Serum levels of calcium, phosphorus, alkaline phosphatase, magnesium, sodium, potassium, and creatinine, abdominal ultrasonography, and DEXA scan were done for all included neonates. RESULTS: BMC showed significant lower levels in the caffeine compared to control group (p = 0.017). Additionally, BMC was significantly lower in neonates who received caffeine for more than 14 days compared to those who received it for 14 days or less(p = 0.04). BMC showed significant positive correlation to birth weight, gestational age, serum P and significant negative correlation to serum ALP. Caffeine therapy duration was negatively correlated to BMC (r = -0.370, p = 0.000) and positively correlated to serum ALP levels (r = 0.667, p = 0.001). None of the neonates had nephrocalcinosis. CONCLUSIONS: Caffeine administration for more than 14 days in preterm neonates may be associated with lower BMC but not nephrocalcinosis or bone fracture.

Role of lung ultrasound in the assessment of recruitment maneuvers in ventilated preterm neonates with respiratory distress syndrome and its correlation with tracheal IL-6 levels: A randomized controlled trial.

BACKGROUND: This study's aim is to evaluate lung ultrasound (LUS) efficacy in detecting opening and closing lung pressures and its correlation with the tracheal interleukin 6 (IL-6) level. METHOD: This single-blinded randomized controlled study was done at Ain Shams University Children's Hospital neonatal intensive care units, Egypt. It consists of 44 mechanically ventilated preterm neonates with Respiratory Distress Syndrome (RDS). Initial LUS assessment was done followed by randomization to one of 2 groups; group I: 22 patients underwent LUS guided RM and group II: 22 patients underwent non-ultrasound guided RM. Tracheal IL-6 level was measured before and after RM in both groups. RESULTS: The LUS scores showed a sensitivity of 86.7%, specificity of 62.10% and accuracy of 70.45% at the cut-off point >B1 grade. After RM, there was a higher percentage of changes in mean airway pressure (p = 0.03), FiO2 (p = 0.01), PaO2/FiO2 ratio (p = 0.01), and IL-6 (p < 0.01) in group I. The duration of oxygen requirement (6 vs.13.5 days, p = 0.01), invasive ventilation (3 vs.5.5 days, p = 0.03), non-invasive ventilation (2.5 vs. 5 days, p = 0.02) and NICU stay (21.5 vs. 42.5 days, p = 0.03) were less in group I. A positive correlation is found between reaeration score and the duration of O2 requirement (p = 0.002), duration of invasive ventilation (p = 0.001), NICU length of stay (p = 0.002) and negative correlation with PaO2/FiO2 ratio before RM (p = 0.012). The best cut-off point for the reaeration score is >21 with a sensitivity of 75%, specificity of 71.43% and area under the curve of 78.1%. CONCLUSION: LUS-guided RM achieved earlier lowest FiO2, shorter O2 dependency, lesser NICU stay and marked decrease in lung inflammation by decreasing atelectotrauma and shortening the duration of invasive ventilation.

A murine femoral ostectomy model with hardware exchange to assess antibiotic-impregnated spacers for implant-associated osteomyelitis.

Implant-associated osteomyelitis is a chronic infection that complicates orthopaedic surgeries. Once infected, 50 % of patients suffer treatment failure, resulting in high healthcare costs. While various small animal models have been developed to investigate the efficacy of prophylactic and therapeutic treatments, the minute scale of murine-model bone and hardware has been prohibitive for evaluating interventions with a complete implant exchange in the setting of an infected critical defect. To address this, the aim of the present study was to develop a murine femur model in which an initial mid-diaphyseal infection was established by surgical implantation of a titanium screw contaminated with bioluminescent Staphylococcus aureus (Xen36). 7 d after the infection was established, an ostectomy was performed to remove the middle segment (3 mm flanking the infected screw hole) and a bone-cement spacer, with or without impregnated gentamicin, was secured with a plate and screws to fix the septic segmental defect. Longitudinal bioluminescent imaging revealed a significant decrease in Xen36 growth following one-stage revision, with the antibiotic-impregnated spacer treated systemically with vancomycin (p < 0.05). This result was corroborated by a significant decrease in colony forming units (CFU) recovered from spacer, bone, soft tissue and hardware 12 d post-operative (p < 0.05). However, ~ 105 CFU/g Xen36 still persisted within the bone despite a clinical therapeutic regimen. Therefore, the model enables the investigation of new therapeutic strategies to improve upon the current standard of care in a mouse model of implant-associated osteomyelitis that employs reconstruction of a critical defect.

3D printed bioceramics for dual antibiotic delivery to treat implant-associated bone infection.

Surgical implant-associated bone infections (osteomyelitis) have severe clinical and socioeconomic consequences. Treatment of chronic bone infections often involves antibiotics given systemically and locally to the affected site in poly (methyl methacrylate) (PMMA) bone cement. Given the high antibiotic concentrations required to affect bacteria in biofilm, local delivery is important to achieve high doses at the infection site. PMMA is not suitable to locally-deliver some biofilm-specific antibiotics, including rifampin, due to interference with PMMA polymerisation. To examine the efficacy of localised, combinational antibiotic delivery compared to PMMA standards, we fabricated rifampin- and vancomycin-laden calcium phosphate scaffolds (CPS) by three-dimensional (3D) printing to treat an implant-associated Staphylococcus aureus bone infection in a murine model. All vancomycin- and rifampin-laden CPS treatments significantly reduced the bacterial burden compared with vancomycin-laden PMMA. The bones were bacteria culture negative in 50 % of the mice that received sustained release vancomycin- and rifampin-laden CPS. In contrast, 100 % of the bones treated with vancomycin monotherapy using PMMA or CPS were culture positive. Yet, the monotherapy CPS significantly reduced the bacterial metabolic load following revision compared to PMMA. Biofilm persisted on the fixation hardware, but the infection-induced bone destruction was significantly reduced by local rifampin delivery. These data demonstrate that, despite the challenging implant-retaining infection model, co-delivery of rifampin and vancomycin from 3D printed CPS, which is not possible with PMMA, significantly improved the outcomes of implant-associated osteomyelitis. However, biofilm persistence on the fixation hardware reaffirms the importance of implant exchange or other biofilm eradication strategies to complement local antibiotics.

Enteral L-Arginine and Glutamine Supplementation for Prevention of NEC in Preterm Neonates.

Objective. Evaluating the efficacy and safety of arginine and glutamine supplementation in decreasing the incidence of NEC among preterm neonates. Methods. Prospective case-control study done on 75 preterm neonates ≤34 weeks, divided equally into L-arginine group receiving enteral L-arginine, glutamine group receiving enteral glutamine, and control group. Serum L-arginine and glutamine levels were measured at time of enrollment (sample 1), after 14 days of enrollment (sample 2), and at time of diagnosis of NEC (sample 3). Results. The incidence of NEC was 9.3%. There was no difference in the frequency of NEC between L-arginine and control groups (P > 0.05). NEC was not detected in glutamine group; L-arginine concentrations were significantly lower in arginine group than control group in both samples while glutamine concentrations were comparable in glutamine and control groups in both samples. No significant difference was found between groups as regards number of septic episodes, duration to reach full oral intake, or duration of hospital stay. Conclusion. Enteral L-arginine supplementation did not seem to reduce the incidence of NEC. Enteral glutamine may have a preventive role against NEC if supplied early to preterm neonates. However, larger studies are needed to confirm these findings. This work is registered in ClinicalTrials.gov (ClinicalTrials.gov Identifier: NCT01263041).

Effects of pentoxifylline on coagulation profile and disseminated intravascular coagulation incidence in Egyptian septic neonates.

BACKGROUND AND OBJECTIVES: Neonatal sepsis is frequently associated with pathological activation of the coagulation system, leading to microcirculatory derangement and multiple organ dysfunction syndrome (MODS). The key role in the pathogenesis of sepsis has been attributed to proinflammatory cytokines. These trigger the development of disseminated intravascular coagulation (DIC) via the tissue factor-dependent pathway of coagulation. Pentoxifylline (PTX), a methylxanthine derivative that is used in peripheral vascular disease, has the potential to modify inflammatory response. The current work was designed to evaluate the potential protective effects of PTX against sepsis-induced microcirculatory derangement in Egyptian neonates. METHODS: A double-blind placebo-controlled quasi-randomized design was used. Thirty-seven neonates with sepsis were randomly allocated into two groups. Seventeen patients were given PTX (5 mg/kg/h for 6 h; for 6 successive days). Twenty patients received equivalent volume of normal saline and represented the placebo group. Prothrombin time (PT), Activated partial thromboplastin time (APTT), fibrinogen, d-dimer, C-reactive protein (CRP), complete blood count (CBC), also hemodynamic parameters comprising arterial blood pressure, heart rate, capillary refill and urinary output were assessed in both groups before and after treatment. RESULTS: Coagulation parameters in the two groups showed no significant differences. However, a higher incidence of DIC was observed in the placebo group neonates. PTX significantly lowered the percentage of bleeding (P = 0.0128) and less frequent use of FFP was observed in the PTX group (35.53% in PTX group vs. 80% in placebo group, P = 0.003). Incidence of MODS was significantly lower (P = 0.037) and hospital stay duration of survivors was significantly shorter (P = 0.044) in the PTX treated-infants. CONCLUSION: Pentoxifylline protects against sepsis-induced microcirculatory derangement in neonates. It significantly lowered the incidence of bleeding and MODS and shortened the length of hospital stay.

Bone mineral content measured by DEXA scan in preterm neonates receiving total parentral nutrition with and without phosphorus supplementation.

Intravenous phosphorus preparation was not available in Egypt till recently. So we aimed to prove the positive effect of adding intravenous phosphorus to total parentral nutrition (TPN) on calcium (Ca) and phosphorus (PO4) metabolism ofpreterm neonates by measuring bone mineral content (BMC) using DEXA scan. A case-control study was conducted in NICU of Obstetric and Gynecology Hospital of Ain Shams University which is a tertiary care unit in Cairo. Thirty preterm infants were prospectively enrolled in the study divided into 2 groups; 15 preterm infants received TPN with phosphorus supplementation (group 1) and 15 preterm received TPN without phosphorus supplementation (group 2). Serum Ca, PO4 and alkaline phosphatase (ALP) assay were done together with urinary calcium/creatinine (Ca/Cr) ratio, abdominal ultrasound and DEXA scan. There were no significant difference regarding serum Ca and PO4 between group 1 and 2. Yet there were highly significant increase in serum ALP and urinary Ca/Cr ratio in group 2 compared to group 1 (p = 0.001). Also group 1 had significantly higher BMC compared to group 2 even with TPN duration less than 15 days (p = 0.001). BMC was significantly positively correlated with G.A and B.W in both groups and was significantly negatively correlated with serum ALP in group 2 and with urinary calcium/creatinine ratio in group 1. Duration of TPN as short as 2 weeks can affect negatively the BMC as documented by DEXA scan in preterm infants receiving TPN without phosphorus supplementation.

A potential mechanism for age-related declines in patellar tendon biomechanics.

Injuries to soft tissues such as tendons are becoming ever more frequent among the elderly. While increasing levels of activity likely contribute to these injuries, age-related declines in tendon strength may also be important. Whether these declines in biomechanical properties are associated with changes in fibril diameter or collagen type remains in question. In this study, age-related changes were investigated in patellar tendons from young adult rabbits (1-year old, n = 17) and from rabbits at the onset of senescence (4-year old, n = 33). Patellar tendon biomechanics was correlated with both collagen fibril diameter and with the presence of type V collagen, a known regulator of collagen fibril diameter. We hypothesize that (a) aging from I to 4 years results in significant reductions in patellar tendon biomechanical properties, and (b) these age-related declines are associated with smaller fibril diameters and with the presence of type V collagen. Maximum stress declined 25% between I and 4 years of age (100.7 +/- 5.6 MPa and 74.3 +/- 3.4 MPa, respectively, p < 0.0003) (mean +/- SEM) and strain energy density declined 40% (p < 0.001). The distribution of collagen fibrils from 4-year old rabbits was skewed significantly towards smaller diameters compared to fibrils from 1-year old rabbits (p < 0.001). Type V collagen was observed only in the 4-year old rabbit tendons. These correlations suggest that with increasing age after skeletal maturity, type V collagen may help to regulate the assembly and thus diameter of collagen fibrils and thereby adversely affect patellar tendon strength.

In vitro characterization of mesenchymal stem cell-seeded collagen scaffolds for tendon repair: effects of initial seeding density on contraction kinetics.

Mesenchymal stem cells (MSCs) were isolated from bone marrow, culture-expanded, and then seeded at 1, 4, and 8 million cells/mL onto collagen gel constructs designed to augment tendon repair in vivo. To investigate the effects of seeding density on the contraction kinetics and cellular morphology, the contraction of the cell/collagen constructs was monitored over time up to 72 h in culture conditions. Constructs seeded at 4 and 8 million cells/mL showed no significant differences in their gross appearance and dimensions throughout the contraction process. By contrast, constructs seeded at 1 million cells/mL initially contracted more slowly and their diameters at 72 h were 62 to 73% larger than those seeded at higher densities. During contraction, MSCs reoriented and elongated significantly with time. Implants prepared at higher seeding densities showed more well aligned and elongated cell nuclei after 72 h of contraction. Changes in nuclear morphology of the MSCs in response to physical constraints provided by the contracted collagen fibrils may trigger differentiation pathways toward the fibroblastic lineage and influence the cell synthetic activity. Controlling the contraction and organization of the cells and matrix will be critical for successfully creating tissue engineered grafts.

Cardiac achalasia in children. Dilatation or surgery?

Surgical treatment of cardiac achalasia in children is still the main line of treatment with a success rate of 70-80%. Balloon dilatation is less widely used due to inappropriate size of balloons. The authors report on their experience in 11 children with cardiac achalasia over the last 7 years using balloon dilatation as the treatment of choice, 8 boys and 3 girls with ages ranging from 1.5-14 years (average 7.5 years) were investigated. One family (brother and sister) presented with no glucocorticoid deficiency or other anomalies, one patient had mental retardation, the rest had no associated anomalies. All patients presented with vomiting, 7 with dysphagia, 6 with loss of weight, 5 with recurrent chest infection and 2 with retrosternal pain. Radiological diagnosis was accurate in all patients, endoscopy with biopsy were done to confirm diagnosis and exclude other pathology, manometry yielded positive results in 4 patients. Dilatation was done under general anesthesia with fluoroscopic control, balloons were used over a guide wire (balloon sizes were 18-35 mm). Seven patients had 2 sessions and 4 had 3 sessions with radiological follow-up after the second dilatation. Follow-up ranged from 2-7 years: excellent results were achieved in 8 patients (72.7%) with disappearance of symptoms and marked radiologic improvement, 2 still have mild symptoms with overall success (90.9%), one had mild gastroesophageal reflux, controlled medically, and one had mild dysphagia but his status was improved compared to that before dilatation. One patient had recurrent dysphagia necessitating cardiomyotomy (9.1%). Results were not related to age or sex. The authors recommend balloon dilatation in children with cardiac achalasia as the treatment of choice or even as the only feasible treatment.

Perspectives on cell and collagen composites for tendon repair.

Cell and matrix composites recently have been used to repair tendons and ligaments. In the current study the authors briefly review prior studies in this area, and the contributions these findings have made toward solving this clinical problem. The authors then provide a perspective on the necessary characteristics that the cells and delivery vehicles of these composites must possess, separately and in combination, to function successfully after surgery. The authors conclude by applying these functional tissue engineering principles to two tendon injury models in which mesenchymal stem cells have been suspended in Type I collagen gel to form composites for patellar and Achilles tendon repair. In the first study, mesenchymal stem cells were suspended in gel (5 million cells/mL) with no attempt to align the cells during incubation. The resulting composites were implanted in window defects in one patellar tendon in the rabbit knee, with gel alone in a matching defect on the contralateral side. Biomechanical evaluation at 4 weeks showed that the material properties of the mesenchy-mal stem cell based repairs were 18% to 33% greater than results for contralateral controls. In the second study, mesenchymal stem cells were suspended in gel (4 million cells/mL), contracted on a tensioned suture during incubation, placed in an Achilles gap defect, and compared with repairs of contralateral gap injuries containing suture alone (controls). By 4 weeks, the repairs treated with mesenchymal stem cells had achieved twice the structural properties of the contralateral controls and 50% to 60% of the stiffness and strength of normal tendons that were not surgically treated. In addition, the material properties of the repairs treated with mesenchymal stem cells had increased with time to 37% of normal by 12 weeks after surgery. Both studies reveal the benefits of using pluripotential cells in a collagen gel matrix, and suggest additional research that might enhance the repair quality of healing tendons.

Autologous mesenchymal stem cell-mediated repair of tendon.

Mesenchymal stem cells (MSCs) were isolated from bone marrow of 18 adult New Zealand White rabbits. These cells were culture expanded, suspended in type I collagen gel, and implanted into a surgically induced defect in the donor s right patellar tendon. A cell-free collagen gel was implanted into an identical control defect in the left patellar tendon. Repair tissues were evaluated biomechanically (n = 13) and histomorphometrically (n = 5) at 4 weeks after surgery. Compared to their matched controls, the MSC-mediated repair tissue demonstrated significant increases of 26% (p < 0.001), 18% (p < 0. 01), and 33% (p < 0.02) in maximum stress, modulus, and strain energy density, respectively. Qualitatively, there appeared to be minor improvements in the histological appearance of some of the MSC- mediated repairs, including increased number of tenocytes and larger and more mature-looking collagen fiber bundles. Morphometrically, however, there were no significant left-right differences in nuclear aspect ratio (shape) or nuclear alignment (orientation). Therefore, delivering a large number of mesenchymal stem cells to a wound site can significantly improve its biomechanical properties by only 4 weeks but produce no visible improvement in its microstructure.

Microbiological status of Egyptian prawn.

A total of 110 prawn individuals were collected from different markets at Cairo and Giza Governorates. The average counts of Aerobes, Psychrophiles, Enterobacteriaceae, Coliforms and Staphylococci were 5 x 10(3), 3 x 10(2), less than 2 x 10(2), less than 3 and 2 x 10(2) organisms per gram newly caught prawn sample, respectively. Such counts were significantly increased in samples collected from markets including raw prawn in shell, raw peeled samples and frozen samples either peeled or in shell. Arizona group, Escherichia coli, Enterobacter group, Proteus group, Providencia group A & B, Shigella group and Staphylococcus aureus could be isolated from examined samples with variable percentages. The public health significance of isolated organisms is discussed.

Effect of temperature on initial bacteria of prawn.

This study was carried out to evaluate the effect of heat and cold on the microorganisms existing in prawn. Roasting for 5 min, boiling for 10 min and storage at -18 degrees C for 10, 20 and 30 days were applied on raw prawn to study the effect of each treatment on the bacterial load. The average counts of APC (aerobic plate count) at 25 degrees C and 0 degree C, Enterobacteriaceae, Coliforms and Staphylococci were 1.3 x 10(7), 6 x 10(4), 2 x 10(2) and 3 x 10(3) organisms per gram raw prawn sample, respectively, then reduced to 10(4), 8 x 10(2), 3 x 10(3), less than 3 and 3 x 10(2) organisms per gram roasted prawn in shell, respectively. Such counts were more reduced in roasted peeled samples. Boiling reduced the average counts of APC at 25 degrees C and 0 degrees C, Enterobacteriaceae, Coliforms and Staphylococci from 8 x 10(8), 2 x 10(5) 2 x 10(7), 3 x 10 and 3 x 10(4) organisms per gram raw prawn sample to 2 x 10(5), 3 x 10(3), 2 x 10(2), less than 3 and 4 x 10(2) organisms, respectively. Concerning freezing storage, it could be observed that the average counts of APC at 25 degrees C and 0 degree C, Enterobacteriaceae, Coliforms and Staphylococci were reduced from 4 x 10(7), 5 x 10(5), 3 x 10(5), 10(3) and 3 x 10(2) organisms per gram raw sample to 5 x 10(4), 10(3), 3 x 10(2), 10 and less than 2 x 10(2) organisms per gram after freezing storage for 30 days.

Sodium chloride-induced hypergastrinaemia in rats.

In this study the effect of Nac1 on plasma immunoreactive gastrin was investigated. I.P. administration of sodium chloride (0.9%) in a dose of 1 ml/kg.b.w. for 7 days in rats, produced a significant rise in level of sodium ion in plasma. This hypernatraemia was also accompanied by significant rise in values of plasma immunoreactive gastrin. The mechanism(s) of this sodium chloride-induced release of gastrin is discussed.

Pathologic changes in testis and epididymis of infertile leprotic males.

Thirty-two cases of male infertility in patients having leprosy were studied. One case was oligospermic and the remaining 31 cases were azoospermic. Pathologic changes in the testis and epididymis are described and illustrated. An important observation was the presence of obstruction in the tail of the epididymis in five cases and this obstruction was undoubtedly the cause of sterility in these five cases as the head of the epididymis was full of sperm and testicular biopsy was more or less normal. In the remaining 27 cases, the cause of sterility was testicular affection with fibrosis and hyalinization of the seminiferous tubules in most of the cases.

Bilateral testicular biopsy in men with varicocele.

Fifty-two infertile men with varicoceles were subjected to bilateral testicular biopsy to detect the effect of the varicocele on each testis. The results indicate that varicocele can result in infertility primarily through sloughing of immature cells or through arrest of spermatogenesis at the spermatid or primary spermatocyte stage. The effect is bilateral but is more marked on the varicocele side. However, the presence of a varicocele could not explain the infertility of seven men with normal biopsies and of four men with a normal biopsy on the varicocele side and arrest on the other side.