Sutureless bowel anastomosis using Nd:YAG laser

Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis.     

Histidine, histamine, and the neuroregulation of food intake: a review and hypothesis

Feeding, a behavior regulated by the central nervous system (CNS), includes the acquisition of specific essential nutrients and the maintenance of energy balance. Modulation of feeding behavior is a normal part of survival, but certain pathological conditions interrupt or modify regulatory aspects of feeding, thereby leading to inappropriate intake. This review examines aspects of metabolism associated with the anorexia seen in animals suffering from protein-energy malnutrition (PEM). The main focus is the indispensable amino acid histidine (His), the biosynthetic precursor of the neurotransmitter histamine (HA). In kwashiorkor-like PEM, His is elevated in plasma and brain, whereas all other indispensable amino acids are decreased. The elevation of His in the brain is to concentrations five times normal. Because the rate of HA synthesis in the brain is a function of the His concentration, His elevation raises the possibility of a profound direct effect of CNS function. In children, PEM consistently produces the symptoms of depressed food intake, edema, growth failure, and psychomotor changes. One known central effect of HA is the stimulation of ACTH and corticosteroid release. Based on these observations, the hypothesis being examined is as follows: one component of the pathophysiological neuroregulation of food intake involved the His-induced variation of HA concentration in the hypothalamus and the subsequently altered neurochemical activity at the corticotropin-releasing factor (CRF) neurons o the paraventricular nucleus (PVN).     

Immediate and delayed cord clamping in infants born between 24 and 32 weeks: a pilot randomized controlled trial.

OBJECTIVE: This pilot study's aim was to establish feasibility of a protocol for delayed cord clamping (DCC) versus immediate cord clamping (ICC) at preterm birth and to examine its effects on initial blood pressure and other outcomes. STUDY DESIGN: A randomized controlled trial recruited 32 infants between 24 and 32 weeks. Immediately before delivery, mothers were randomized to ICC (cord clamped at 5 to 10 seconds) or DCC (30- to 45-second delay in cord clamping) groups. RESULTS: Intention-to-treat analyses revealed that the DCC group were more likely to have higher initial mean blood pressures (adjusted OR 3.4) and less likely to be discharged on oxygen (adjusted OR 8.6). DCC group infants had higher initial glucose levels (ICC=36 mg/dl, DCC=73.1 mg/dl; p=0.02). CONCLUSION: The research design is feasible. The immediate benefit of improved blood pressure was confirmed and other findings deserve consideration for further study.     

Gastroschisis: ultrasonographic diagnosis, perinatal embryology, surgical and obstetric treatment and outcomes

The embryology and onset time of gastroschisis are poorly understood. This paper reviews 22 cases of the condition seen at the Children's Hospital of Eastern Ontario between 1975 and 1986. Sixteen cases were judged to be of the perinatal and 6 of the early type. Ultrasonography revealed the actual time of development in one case and the probable time in another. In 20 cases the defect was closed primarily and in 2 by a staged procedure (Silon pouch). Nineteen infants (86.4%) survived. In all cases the umbilical vasculature was normal and all were right-sided. Other anomalies were rare and less important. Two clear examples of rupture of the umbilical ring are documented. Ultrasonography had been performed in 10 infants, usually for intrauterine growth retardation, and gastroschisis was diagnosed in 4 of these. Delivery was by cesarean section in six. Marked meconium staining occurred in 16 (73%), 7 of whom had subglottic aspiration of meconium. The average birth weight was 2480 g. Ultrasonography is recommended in all cases of intrauterine growth retardation with careful examination of the umbilical area to establish the presence and time of onset of gastroschisis. Vaginal delivery appears to be the route of choice for delivery.     

Clinical and histological patterns of dermatofibromas of the nail apparatus

True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative.     

Cell cycle regulation and the p53 tumor suppressor protein.

Somatic mutations of the p53 gene have been implicated as causal events in the formation of a large number of common human tumors. Several lines of evidence suggest that the nuclear phosphoprotein encoded for by the wild-type gene (wt-p53) plays a role in regulating cell proliferation. Wt-p53 protein encodes a potent negative growth regulatory function that is lacking in mutant forms of the protein found in human tumors. In this review, the relationship between the expression of wt-p53 protein and cell proliferation is examined with emphasis on recent studies that provide clues as to the possible role that p53 plays in cell cycle regulation. A model for the action of p53 in regulating cell proliferation is proposed in which wt-p53 acts as a "checkpoint" protein to control the transit of cells through the restriction point in late G1-phase. After cells pass this "checkpoint" they become committed to enter S-phase and initiate DNA replication. This checkpoint function may be defective in cells that lack p53, express mutant p53, or in which the antiproliferative form of the protein is functionally inactive. Under these conditions stringent control of the initiation of DNA replication may no longer be possible, providing an environment conducive to the emergence oncogenic clones.