An effective pyloromyotomy length in infants undergoing laparoscopic pyloromyotomy

BACKGROUND: Traditional management of pyloric stenosis has consisted of open pyloromyotomy during which the surgeon is able to palpate and determine whether the hypertrophied pylorus has been completely divided. During the last decade, laparoscopic pyloromyotomy has become an increasingly popular approach for this condition. The purpose of this study was to determine whether there is an effective pyloromyotomy length that will allow the surgeon to feel confident that a complete pyloromyotomy was performed with the laparoscopic approach. METHODS: All infants undergoing laparoscopic pyloromyotomy from October 1999 through October 2003 at a single institution were retrospectively studied. Clinical variables collected included the patient's age, gender, electrolyte status on admission, the elapsed time from admission to operation, ultrasonographic dimensions of the hypertrophied pylorus, operative time, the length of the pyloromyotomy performed, the time to initial and to full feedings, and the duration of the postoperative hospitalization. RESULTS: One hundred seventy-one patients comprised the study group. The age (mean +/- standard deviation) at the time of operation was 5.2 +/- 2.8 weeks. The mean preoperative ultrasonic measurements for both pyloric thickness and pyloric length were 4.3 +/- 0.7 mm and 19.5 +/- 2.8 mm, respectively. The average pyloromyotomy incision length for this entire group was 1.9 +/- 0.21 cm. The mean operative time was 23.5 +/- 8.3 minutes. There were no mucosal perforations, no conversions to an open procedure, and no evidence for an incomplete pyloromyotomy. CONCLUSIONS: Laparoscopic pyloromyotomy is a safe and effective technique for infants with pyloric stenosis. A pyloromyotomy incision length of approximately 2 cm appears to be an effective measure of a complete pyloromyotomy.     

Prevalence of malignancy within cytologically indeterminate thyroid nodules

BACKGROUND: The optimal management of cytologically indeterminate thyroid nodules is controversial given the variable malignancy rates reported in this patient population. We examined the prevalence of malignancy within cytologically indeterminate follicular thyroid lesions in an attempt to predict malignancy based on cytologic features. METHODS: Cytopathology reports obtained after fine-needle aspiration biopsy (FNAB) examination of indeterminate follicular thyroid lesions were examined over a 4-year period. The prevalence of malignancy on final histology was determined in 4 indeterminate cytologic categories. RESULTS: A total of 107 records were available (91 women, 16 men). The mean patient age was 45.4 +/- 16 years. Forty-eight patients (45%) underwent surgery and had histopathologic diagnosis, while 57 patients did not have surgery. The prevalence of malignancy in patients who underwent thyroidectomy was 42% (20 of 48). CONCLUSIONS: The high prevalence of malignancy within indeterminate follicular lesions may necessitate thyroidectomy for patients with indeterminate follicular lesions on FNAB examination.     

Protein kinase C regulates ionic conductance in hippocampal pyramidal neurons: electrophysiological effects of phorbol esters.

The vertebrate central nervous system contains very high concentrations of protein kinase C, a calcium- and phospholipid-stimulated phosphorylating enzyme. Phorbol esters, compounds with inflammatory and tumor-promoting properties, bind to and activate this enzyme. To clarify the role of protein kinase C in neuronal function, we have localized phorbol ester receptors in the rat hippocampus by autoradiography and examined the electrophysiological effects of phorbol esters on hippocampal pyramidal neurons in vitro. Phorbol esters blocked a calcium-dependent potassium conductance. In addition, phorbol esters blocked the late hyperpolarization elicited by synaptic stimulation even though other synaptic potentials were not affected. The potencies of several phorbol esters in exerting these actions paralleled their affinities for protein kinase C, suggesting that protein kinase C regulates membrane ionic conductance.     

Subcellular sites of synthesis of phosphatidylglycerol and phosphatidylinositol in type II pneumonocytes

The subcellular sites of synthesis of phosphatidylinositol and phosphatidylglycerol in type II pneumonocytes isolated from lungs of adult rats were investigated. Microsomes contained approximately 34% of the total cellular activity of CDP-diacylglycerol: inositol 3-phosphatidyltransferase (EC 2.7.8.11) but less than 10% of the total activity of CDP-diacylglycerol: glycerol 3-phosphate phosphatidyltransferase (EC 2.7.8.5) and the latter activity could be attributed to mitochondrial contamination of the microsomal fraction. A crude mitochondrial fraction contained approximately 90% of the total cellular activity of CDP-diacylglycerol: glycerol 3-phosphate phosphatidyltransferase and also contained more than 50% of the total CDP-diacylglycerol: inositol 3-phosphatidyltransferase activity. When the crude mitochondrial fraction was subfractionated by use of discontinuous density gradient centrifugation, the distribution of CDP-diacylglycerol: inositol 3-phosphatidyltransferase activity was similar to that of NADPH: cytochromec reductase activity but dissimilar to the distribution of CDP-diacylglycerol: glycerol 3-phosphate phosphatidyltransferase activity which resembled that of succinate dehydrogenase. Electron microscopy of subcellular fractions revealed that fractions rich in CDP-diacylglycerol: inositol 3-phosphatidyltransferase activity contained numerous smooth membrane vesicles, whereas fractions rich in CDP-diacylglycerol: glycerol 3-phosphate phosphatidyltransferase activity contained mainly mitochondria. We conclude that the subcellular sites of synthesis of phosphatidylinositol and phosphatidylglycerol in type II pneumonocytes are most likely the endoplasmic reticulum and mitochondria, respectively. The results of this investigation were presented, in part, at the 73rd annual meeting of the American Society of Biological Chemists     

Peripheral-type benzodiazepine receptors in endocrine organs: autoradiographic localization in rat pituitary, adrenal, and testis

We have used [3H]Ro5-4864, a ligand selective for peripheral-type benzodiazepine receptors, to identify and localize peripheral-type benzodiazepine receptors in endocrine organs. Autoradiographic studies reveal an uniform distribution of [3H]Ro5-4864 binding sites within the anterior, intermediate, and posterior lobes of the pituitary gland, with highest concentrations present in the posterior pituitary. In rat adrenal gland, specific binding sites for [3H]Ro5-4864 are found only in the adrenal cortex, with highest density in the zona glomerulosa and significantly lower concentrations in the zona fasciculata and zona reticularis. [3H]Ro5-4864-associated silver grains in the testis are intensely localized over the interstitial tissue; low concentrations of silver grains are present over the epithelium of the seminiferous tubules but are absent from the tubular lumen. These studies demonstrate a differential and discrete localization of peripheral-type benzodiazepine receptors in rat pituitary, adrenal, and testis.     

Barotrauma and hypotension resulting from jet ventilation in critically ill patients

We present the first reports of pneumoperitoneum secondary to jet ventilation, barotrauma secondary to jet ventilation through the suction port of a fiberoptic laryngoscope, and hypotension due to jet ventilation via nasotracheal and orotracheal catheters. We suggest that minimizing airway pressure and using jet catheters with side holes may help decrease the risk of such complications. We cannot, at present, recommend the use of hand-held jet ventilators unless both adequate exhalation space is guaranteed and direct impingement of the catheter's tip on the mucosal surface is avoided.     

Cutaneous blisters and carbon monoxide poisoning

We present the cases of three patients with skin blisters following carbon monoxide (CO) poisoning. Their blisters appeared to be related to the severity of the poisoning (HbCO levels of more than 40%). Two of the three patients died despite aggressive initial 100% surface oxygen followed by hyperbaric oxygen therapy. The pathophysiology of this type of blister remains unresolved. It could result from pressure necrosis alone or from a combination of pressure necrosis and direct CO inhibition of tissue oxidative enzymes. Although skin involvement as a result of CO poisoning is less frequently reported today than in the past (perhaps because of misidentified burns or because of more aggressive resuscitation and treatment protocols), the physician should recognize that such blisters may signal severe CO poisoning.     

Report of a Consensus Conference on Transplant Program Quality and Surveillance

Public reports of organ transplant program outcomes by the US Scientific Registry of Transplant Recipients have been both groundbreaking and controversial. The reports are used by regulatory agencies, private insurance providers, transplant centers and patients. Failure to adequately adjust outcomes for risk may cause programs to avoid performing transplants involving suitable but high‐risk candidates and donors. At a consensus conference of stakeholders held February 13–15, 2012, the participants recommended that program‐specific reports be better designed to address the needs of all users. Additional comorbidity variables should be collected, but innovation should also be protected by excluding patients who are in approved protocols from statistical models that identify underperforming centers. The potential benefits of hierarchical and mixed‐effects statistical methods should be studied. Transplant centers should be provided with tools to facilitate quality assessment and performance improvement. Additional statistical methods to assess outcomes at small‐volume transplant programs should be developed. More data on waiting list risk and outcomes should be provided. Monitoring and reporting of short‐term living donor outcomes should be enhanced. Overall, there was broad consensus that substantial improvement in reporting outcomes of transplant programs in the United States could and should be made in a cost‐effective manner.     

Transplanted neural stem cells survive,differentiate, and improve neurological motor function after experimental traumatic brain injury

OBJECTIVE: Using the neural stem cell (NSC) clone C17.2, we evaluated the ability of transplanted murine NSCs to attenuate cognitive and neurological motor deficits after traumatic brain injury. METHODS: Nonimmunosuppressed C57BL/6 mice (n = 65) were anesthetized and subjected to lateral controlled cortical impact brain injury (n = 52) or surgery without injury (sham operation group, n = 13). At 3 days postinjury, all brain-injured animals were reanesthetized and randomized to receive stereotactic injection of NSCs or control cells (human embryonic kidney cells) into the cortex-hippocampus interface in either the ipsilateral or the contralateral hemisphere. One group of animals (n = 7) was killed at either 1 or 3 weeks postinjury to assess NSC survival in the acute posttraumatic period. Motor function was evaluated at weekly intervals for 12 weeks in the remaining animals, and cognitive (i.e., learning) deficits were assessed at 3 and 12 weeks after transplantation. RESULTS: Brain-injured animals that received either ipsilateral or contralateral NSC transplants showed significantly improved motor function in selected tests as compared with human embryonic kidney cell-transplanted animals during the 12-week observation period. Cognitive dysfunction was unaffected by transplantation at either 3 or 12 weeks postinjury. Histological analyses showed that NSCs survive for as long as 13 weeks after transplantation and were detected in the hippocampus and/or cortical areas adjacent to the injury cavity. At 13 weeks, the NSCs transplanted ipsilateral to the impact site expressed neuronal (NeuN) or astrocytic (glial fibrillary acidic protein) markers but not markers of oligodendrocytes (2'3'cyclic nucleotide 3'-phosphodiesterase), whereas the contralaterally transplanted NSCs expressed neuronal but not glial markers (double-labeled immunofluorescence and confocal microscopy). CONCLUSION: These data suggest that transplanted NSCs can survive in the traumatically injured brain, differentiate into neurons and/or glia, and attenuate motor dysfunction after traumatic brain injury.