Gallstone disease in the elderly: are older patients managed differently?

Background  

This study aimed to describe the differences in the management of symptomatic gallstone disease within different elderly groups and to evaluate the association between older age and surgical treatment.     

Thrombocytosis accompanying urinary tract infection suggests obstruction or abscess

OBJECTIVE: Reactive thrombocytosis can be found in patients with different types of infections, including upper urinary tract infection (UTI). In this study, we determined whether thrombocytosis in patients with upper UTI is a random phenomenon or is related to complications associated with the UTI. METHODS: We reviewed the charts of patients admitted to the urology department with a diagnosis of upper UTI and thrombocytosis (platelet count >500 x 10(9)/L) in the years 1991 to 2003 (study group). Patients admitted to the urology department in the year 2003 with a diagnosis of upper UTI without thrombocytosis served as the control group. RESULTS: The study group consisted of 83 patients admitted to the urology department with a diagnosis of upper UTI and thrombocytosis (mean platelet count, 593 x 10(9)/L; SD, 88; range, 501-949). The control group consisted of 99 patients. An obstructed kidney was found in 54 patients (65%) of the study group and in 18 patients (18%) of the control group (P < .00001). Perinephric abscess was found in 7 patients (8%) in the study group compared with none in the control group (P < .003). The positive predictive value of thrombocytosis for kidney obstruction or abscess in patients with upper UTI was 71%. Nephrectomy of a nonfunctioning infected kidney was required in 6 patients of the study group (7%) and 2 of the control group (P = .14). In 26 patients (31%) of the study group, the finding of thrombocytosis preceded the diagnosis of the complication (by a median period of 3 days). In these patients, thrombocytosis was essentially an early marker for the complication. CONCLUSIONS: Thrombocytosis in a patient with upper UTI is not a random phenomenon. It is a marker of kidney obstruction or perinephric abscess. The finding of thrombocytosis in a patient with upper UTI should alert the attending physician to actively search for these complications. Cross-sectional imaging study (abdominal ultrasonography or computed tomography) should be performed.     

Odontogenic tumours in children and adolescents: a study of 78 Nigerian cases.

BACKGROUND: There is paucity of literature on odontogenic tumours in children and adolescents. Available records are difficult to compare due to differences in study criteria. To contribute to the records, a 20-year study of odontogenic tumours on the basis of the WHO classification (Kramer et al., 1992) in Nigerian African children and adolescents < or =18 years of age was undertaken. MATERIAL: A retrospective survey of oral/jaw tumours and allied lesions in children and adolescents < or =18 years of age seen at the Maxillofacial Unit, Ahmadu Bello University Teaching Hospital, Kaduna, Nigeria between 1979 and 1998. Data collected were histopathologic type, age, clinical features, radiologic appearance, treatment and record of recurrence. METHOD: Odontogenic tumours selected using the WHO classification were used for further study. Data were collected from case notes, radiographs, histopathologic reports and follow-up records. Information retrieved was used to complete a questionnaire and subjected to analysis. RESULTS: Two hundred and fifty-two (252) subjects < or =18 years were recorded, from which 78 (31%) had odontogenic tumours. Among seven types of odontogenic tumours seen, ameloblastoma (54%), odontogenic myxoma (19%) and adenomatoid odontogenic tumour (9%) were predominant. All patients seen were from 6 to 18 years with more than half (53%) between 15 and 18 years of age. A patient with multiple, bilateral odontomas of the maxilla and mandible resembling Herrmann's syndrome was recorded. Seventy-three patients were treated using enucleation (37%), dentoalveolar resection with preservation of lower border (15%) and segmental resection (48%). Five patients absconded after tumour diagnosis. No tumour recurrence was recorded in 65 treated cases followed-up for between 2 months and 10 years. CONCLUSION: This report shows that while ameloblastoma was the predominant odontogenic tumour, its frequency in Nigerian African children was lower than in the adult population. A case resembling Herrmann's syndrome is also presented.     

Retrograde regulation of motoneuron differentiation by muscle beta-catenin

Synapse formation requires proper interaction between pre- and postsynaptic cells. In anterograde signaling, neurons release factors to guide postsynaptic differentiation. However, less is known about how postsynaptic targets retrogradely regulate presynaptic differentiation or function. We found that muscle-specific conditional knockout of beta-catenin (Ctnnb1, also known as beta-cat) in mice caused both morphologic and functional defects in motoneuron terminals of neuromuscular junctions (NMJs). In the absence of muscle beta-catenin, acetylcholine receptor clusters were increased in size and distributed throughout a wider region. Primary nerve branches were mislocated, whereas secondary or intramuscular nerve branches were elongated and reduced in number. Both spontaneous and evoked neurotransmitter release was reduced at the mutant NMJs. Furthermore, short-term plasticity and calcium sensitivity of neurotransmitter release were compromised in beta-catenin-deficient muscle. In contrast, the NMJ was normal in morphology and function in motoneuron-specific beta-catenin-deficient mice. Taken together, these observations indicate a role for muscle beta-catenin in presynaptic differentiation and function, identifying a previously unknown retrograde signaling in the synapse formation and synaptic plasticity.     

A monodactyl nonavian dinosaur and the complex evolution of the alvarezsauroid hand

Digital reduction is a striking evolutionary phenomenon that is clearly exemplified in theropod dinosaurs by the functionally didactyl manus of tyrannosaurids, the flight-adapted manus of birds (Aves), and the tridactyl but digit II-dominated manus of alvarezsauroids. The enlargement of manual digit II in alvarezsauroids and the concurrent reduction of the lateral digits have been interpreted as adaptations for digging, although no detailed biomechanical analysis of hand function has so far been carried out for this group. In the derived alvarezsauroid clade Parvicursorinae, the lateral digits are so small as to be presumably vestigial. Here we report a new alvarezsauroid, Linhenykus monodactylus gen. et sp. nov., based on a specimen from the Upper Cretaceous Wulansuhai Formation of Inner Mongolia, China. Cladistic analysis identifies Linhenykus as the most basal parvicursorine, and digit II of the manus retains a slender morphology and other primitive features. However, Linhenykus is also highly apomorphic in exhibiting the most extreme reduction of the lateral manual digits seen in any alvarezsauroid. Phalanges are retained only on the most medial digit (digit II), making Linhenykus the only known functionally monodactyl nonavian dinosaur. Other parvicursorines are more primitive in retaining a tridactyl manus but more derived in that digit II is highly robust and shows other apomorphic features in both of its phalanges. The unexpected combination of features seen in the hand of Linhenykus points to a complex mosaic pattern of manual evolution in alvarezsauroids, with loss of the presumably vestigial outer digits being decoupled from change in the form of digit II.     

Vascular-mesenchymal cross-talk through Vegf and Pdgf drives organ patterning

The initiation of de novo testis cord organization in the fetal gonad is poorly understood. Endothelial cell migration into XY gonads initiates testis morphogenesis. However, neither the signals that regulate vascularization of the gonad nor the mechanisms through which vessels affect tissue morphogenesis are known. Here, we show that Vegf signaling is required for gonad vascularization and cord morphogenesis. We establish that interstitial cells express Vegfa and respond, by proliferation, to endothelial migration. In the absence of vasculature, four-dimensional imaging of whole organs revealed that interstitial proliferation is reduced and prevents formation of wedge-like structures that partition the gonad into cord-forming domains. Antagonizing vessel maturation also reduced proliferation. However, proliferation of mesenchymal cells was rescued by the addition of PDGF-BB. These results suggest a pathway that integrates initiation of vascular development and testis cord morphogenesis, and lead to a model in which undifferentiated mesenchyme recruits blood vessels, proliferates in response, and performs a primary function in the morphogenesis and patterning of the developing organ.     

Is mechanical ventilation associated with intraventricular hemorrhage in preterm infants?

Background

The impact of mechanical ventilation on the incidence of intraventricular hemorrhage (IVH) in very low birth weight (VLBW) infants is unknown, simply because the vast majority of these infants have been routinely intubated and mechanically ventilated. There is a growing interest in the use of early nasal continuous positive airway pressure (ENCPAP) and avoiding mechanical ventilation.

Objectives

To examine the role of mechanical ventilation since delivery room in determining severe IVH in VLBW infants in two neonatal units that follow the same strategy of respiratory management using ENCPAP.

Methods

We collected data on delivery room intubation and mechanical ventilation during the first 3 days of life in VLBW infants. Logistic regression model was constructed to test the relationship between early mechanical ventilation and the diagnosis of severe IVH after controlling for significant confounding variables, such as BW, gender, duration of mechanical ventilation, and partial pressure of CO₂ (PCO₂).

Results

Of the studied 340 VLBW, 35 infants had severe IVH; most of them received mechanical ventilation that started either in the delivery room (n = 12) or during the first (n = 10) and second (n = 3) days of life. Severe IVH was independently associated with lower BW, mechanical ventilation in the delivery room, and the cumulative duration of mechanical ventilation during the first 3 days. The adjusted odds ratio for severe IVH in infants intubated in delivery room was (OR = 2.7, CI: 1.1–6.6, P = 0.03). Severe IVH was not associated with gender, prenatal steroids, early sepsis, or patent ductus arteriosus.

Conclusions

Mechanical ventilation plays a role in predicting severe IVH. Both the time at which ventilation was initiated and the duration of ventilation are important determinants of severe IVH. Risk for severe IVH in infants who were never intubated in delivery room or during the first 3 days of life is miniscule.