Left ventricular concentric hypertrophy with cardiac magnetic resonance imaging improves risk stratification in patients with Duchenne muscular dystrophy: a prospective cohort study.

BACKGROUND: The development of left ventricular (LV) remodeling has been associated with an increased cardiovascular risk and cardiogenic death, and different patterns of remodeling result in varying levels of prognosis. OBJECTIVE: To investigate the association between different patterns of LV remodeling and clinical outcomes in the preclinical stage of patients with Duchenne muscular dystrophy (DMD). MATERIALS AND METHODS: A total of 148 patients with DMD and 43 sex- and age-matched healthy participants were enrolled. We used the four-quadrant analysis method to investigate LV remodeling based on cardiac magnetic resonance (MR) imaging. Kaplan-Meier curves were generated to illustrate the event-free survival probability stratified by the LV remodeling pattern. Cox regression models were constructed and compared to evaluate the incremental predictive value of the LV remodeling pattern. RESULTS: During the median follow-up period of 2.2 years, all-cause death, cardiomyopathy, and ventricular arrhythmia occurred in 5, 35, and 7 patients, respectively. LV concentric hypertrophy (hazard ratio 2.91, 95% confidence interval 1.47-5.75, P=0.002) was an independent predictor of composite endpoint events. Compared to the model without LV concentric hypertrophy, the model with LV concentric hypertrophy had significant incremental predictive value (chi-square value 33.5 vs. 25.2, P=0.004). CONCLUSION: Age and late gadolinium enhancement positivity were positively correlated with clinical outcomes according to the prediction models. LV concentric hypertrophy was also an independent predictor for risk stratification and provided incremental value for predicting clinical outcomes in the preclinical stage of patients with DMD.

Derivation and validation of diagnostic models for myocardial fibrosis in duchenne muscular dystrophy: assessed by multi-parameter cardiovascular magnetic resonance.

BACKGROUND: Gadolinium-enhanced cardiovascular magnetic resonance (CMR) is the most widely used approach for diagnosing myocardial fibrosis with late gadolinium enhancement (LGE) in cardiomyopathy associated with Duchenne muscular dystrophy. Given the limitations and safety of gadolinium use, we wanted to develop and evaluate multi-parametric pre-contrast CMR models for the diagnosis of LGE and investigate whether they could be utilised as surrogates for LGE in DMD patients. METHODS: A total of 136 DMD patients were prospectively recruited and separated into LGE - and LGE + groups. In the first subset of patients (derivation cohort), regression models for the diagnosis of LGE were built by logistic regression using pre-contrast sequence parameters. In a validation cohort of other patients, the models' performances were evaluated. RESULTS: EF, native T1 and longitudinal strain alone, as well as their combinations form seven models. The model that included EF, native T1 and longitudinal strain had the best diagnostic value, but there was no significant difference in diagnostic accuracy among the other models except EF. In the validation cohort, the diagnosis outcomes of models were moderate consistent with the existence of LGE. The longitudinal strain outperformed the other models in terms of diagnostic value (sensitivity: 83.33%, specificity: 54.55%). CONCLUSIONS: Pre-contrast sequences have a moderate predictive value for LGE. Thus, pre-contrast parameters may be considered only in a specific subset of DMD patients who cannot cooperate for long-time examinations and have contradiction of contrast agent to help predict the presence of LGE. TRIAL REGISTRATION NUMBER (TRN): ChiCTR1800018340 DATE OF REGISTRATION: 20180107.

Longitudinal changes in magnetic resonance imaging biomarkers of the gluteal muscle groups and functional ability in Duchenne muscular dystrophy: a 12-month cohort study.

BACKGROUND: Quantitative magnetic resonance imaging (MRI) is considered an objective biomarker of Duchenne muscular dystrophy (DMD), but the longitudinal progression of MRI biomarkers in gluteal muscle groups and their predictive value for future motor function have not been described. OBJECTIVE: To explore MRI biomarkers of the gluteal muscle groups as predictors of motor function decline in DMD by characterizing the progression over 12 months. MATERIALS AND METHODS: A total of 112 participants with DMD were enrolled and underwent MRI examination of the gluteal muscles to determine fat fraction and longitudinal relaxation time (T1). Investigations were based on gluteal muscle groups including flexors, extensors, adductors, and abductors. The North Star Ambulatory Assessment and timed functional tests were performed. All participants returned for follow-up at an average of 12 months and were divided into two subgroups (functional stability/decline groups) based on changes in timed functional tests. Univariable and multivariable logistic regression methods were used to explore the risk factors associated with future motor function decline. RESULTS: For the functional decline group, all T1 values decreased, while fat fraction values increased significantly over 12 months (P<0.05). For the functional stability group, only the fat fraction of the flexors and abductors increased significantly over 12 months (P<0.05). The baseline T1 value was positively correlated with North Star Ambulatory Assessment and negatively correlated with timed functional tests at the 12-month follow-up (P<0.001), while the baseline fat fraction value was negatively correlated with North Star Ambulatory Assessment and positively correlated with timed functional tests at the 12-month follow-up (P<0.001). Multivariate regression showed that increased fat fraction of the abductors was associated with future motor function decline (model 1: odds ratio [OR]=1.104, 95% confidence interval [CI]: 1.026~1.187, P=0.008; model 2: OR=1.085, 95% CI: 1.013~1.161, P=0.019), with an area under the curve of 0.874. CONCLUSION: Fat fraction of the abductors is a powerful predictor of future motor functional decline in DMD patients at 12 months, underscoring the importance of focusing early on this parameter in patients with DMD.

Clinical utilisation of multimodal quantitative magnetic resonance imaging in investigating muscular damage in Duchenne muscular dystrophy: a study on the association between gluteal muscle groups and motor function.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a neuromuscular disease characterised by progressive muscular weakness and atrophy. Currently, studies on DMD muscle function mostly focus on individual muscles; little is known regarding the effect of gluteal muscle group damage on motor function. OBJECTIVE: To explore potential imaging biomarkers of hip and pelvic muscle groups for measuring muscular fat replacement and inflammatory oedema in DMD with multimodal quantitative magnetic resonance imaging (MRI). MATERIALS AND METHODS: One hundred fifty-nine DMD boys and 32 healthy male controls were prospectively included. All subjects underwent MRI examination of the hip and pelvic muscles with T1 mapping, T2 mapping and Dixon sequences. Quantitatively measured parameters included longitudinal relaxation time (T1), transverse relaxation time (T2) and fat fraction. Investigations were all based on hip and pelvic muscle groups covering flexors, extensors, adductors and abductors. The North Star Ambulatory Assessment and stair climbing tests were used to measure motor function in DMD. RESULTS: T1 of the extensors (r = 0.720, P < 0.01), flexors (r = 0.558, P < 0.01) and abductors (r = 0.697, P < 0.001) were positively correlated with the North Star Ambulatory Assessment score. In contrast, T2 of the adductors (r = -0.711, P < 0.01) and fat fraction of the extensors (r = -0.753, P < 0.01) were negatively correlated with the North Star Ambulatory Assessment score. Among them, T1 of the abductors (b = 0.013, t = 2.052, P = 0.042), T2 of the adductors (b = -0.234, t = -2.554, P = 0.012) and fat fraction of the extensors (b = -0.637, t = - 4.096, P < 0.001) significantly affected the North Star Ambulatory Assessment score. Moreover, T1 of the abductors was highly predictive for identifying motor dysfunction in DMD, with an area under the curve of 0.925. CONCLUSION: Magnetic resonance biomarkers of hip and pelvic muscle groups (particularly T1 values of the abductor muscles) have the potential to be used as independent risk factors for motor dysfunction in DMD.

[Cross-Sectional Study of Nutritional Status and Dietary Nutrient Intake in Children with Duchenne Muscular Dystrophy (DMD) in China].

Objective: To investigate the dietary nutrient intake and the nutritional status of children with Duchenne muscular dystrophy (DMD), and to explore the correlation between them, so as to provide theoretical basis for the formulation of proper nutritional treatment for children with DMD. Methods: A total of 223 children aged 2 to 14 years who came to West China Second University Hospital, Sichuan University from July 2017 to April 2021, and who were diagnosed with DMD by genetic testing were enrolled as the subjects of the study. Dietary assessment was conducted with a 3-day 24-hour dietary recall, and serum vitamin D level was measured by chemiluminescence method. Results: Only 33.2% of the children with DMD were found to be of normal nutritional status. The incidences of stunted growth, underweight, overweight and obesity were 13.5%, 14.4%, 14.3% and 8.1%, respectively. Among the children with DMD, those with serum vitamin D deficiency and insufficiency accounted for 9.0% and 89.7%, respectively. According to the dietary recall of the children with MDM, the daily energy ratio of carbohydrate, protein and fat were (47.40±6.64)%, (14.46±2.22)%, and (38.17±5.30)%, respectively. The daily intake of dietary calcium and vitamin D were (433.32±164.39) mg per day and (155.73±89.30) IU per day, respectively. The ratio of daily protein intake to the estimated average requirement for protein ( P=0.003) and ratio of daily energy intake to the estimated energy requirement ( P=0.007) were lower in children with stunted growth than those of DMD children of normal nutritional status. Conclusion: The dietary structure of children with DMD is obviously not suited to their condition and nutritional deficiency coexists with overnutrition among them. Further research needs to be done for developing appropriate nutritional guidance programs and standardized nutritional management measures for children with DMD.

Global, segmental and layer specific analysis of myocardial involvement in Duchenne muscular dystrophy by cardiovascular magnetic resonance native T1 mapping.

BACKGROUND: Progressive cardiomyopathy accounts for almost all mortality among Duchenne muscular dystrophy (DMD) patients.| Thus, our aim was to comprehensively characterize myocardial involvement by investigating the heterogeneity of native T1 mapping in DMD patients using global and regional (including segmental and layer-specific) analysis across a large cohort. METHODS: We prospectively enrolled 99 DMD patients (8.8 ± 2.5 years) and 25 matched male healthy controls (9.5 ± 2.5 years). All subjects underwent cardiovascular magnetic resonance (CMR) with cine, T1 mapping and late gadolinium enhancement (LGE) sequences. Native T1 values based on the global and regional myocardium were measured, and LGE was defined. RESULTS: LGE was present in 49 (49%) DMD patients. Global native T1 values were significantly longer in LGE-positive (LGE +) patients than in healthy controls, both in basal slices (1304 ± 55 vs. 1246 ± 27 ms, p < 0.001) and in mid-level slices (1305 ± 57 vs. 1245 ± 37 ms, p < 0.001). No significant difference in global native T1 was found between healthy controls and LGE-negative (LGE-) patients. In segmental analysis, LGE + patients had significantly increased native T1 in all analyzed segments compared to the healthy control group. Meanwhile, the comparison between LGE- patients and healthy controls showed significantly elevated values only in the basal anterolateral segment (1273 ± 62 vs. 1234 ± 40 ms, p = 0.034). Interestingly, the epicardial layer had a significantly higher native T1 in LGE- patients than in healthy controls (p < 0.05), whereas no such pattern was noticed in the global myocardium. Epicardial layer native T1 resulted in the highest diagnostic performance for distinguishing between healthy controls and DMD patients in receiver operating curve analyses (area under the curve [AUC] 0.84 for basal level and 0.85 for middle level) when compared to global native T1 and endocardial layer native T1. CONCLUSIONS: Myocardial regional native T1, particularly epicardial native T1, seems to have potential as a novel robust marker of very early cardiac involvement in DMD patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry ( http://www.chictr.org.cn/index.aspx ) ChiCTR1800018340, 09/12/2018, Retrospectively registered.

GMPPB-congenital disorders of glycosylation associate with decreased enzymatic activity of GMPPB.

The congenital disorders of glycosylation (CDG) are a family of metabolic diseases in which glycosylation of proteins or lipids is deficient. GDP-mannose pyrophosphorylase B (GMPPB) mutations lead to CDG, characterized by neurological and muscular defects. However, the genotype-phenotype correlation remains elusive, limiting our understanding of the underlying mechanism and development of therapeutic strategy. Here, we report a case of an individual presenting congenital muscular dystrophy with cerebellar involvement, who presents two heterozygous GMPPB mutations (V111G and G214S). The V111G mutation significantly decreases GMPPB's enzymatic activity. By measuring enzymatic activities of 17 reported GMPPB mutants identified in patients diagnosed with GMPPB-CDG, we discover that all tested GMPPB variants exhibit significantly decreased enzymatic activity. Using a zebrafish model, we find that Gmppb is required for neuronal and muscle development, and further demonstrate that enzymatic activity of GMPPB mutants correlates with muscular and neuronal phenotypes in zebrafish. Taken together, our findings discover the importance of GMPPB enzymatic activity for the pathogenesis of GMPPB-CDG, and shed light for the development of additional indicators and therapeutic strategy.

Collagenous colitis in a child induced by chronic respiratory allergy: A case report.

INTRODUCTION: Collagen colitis (CC) is a microscopic colitis diagnosed by mucosal biopsy and is extremely rare in children. PATIENT CONCERNS: We reported a child with severe persistent diarrhea that could not be relieved with traditional diarrheal treatment. No abnormalities were found after multiple colonoscopies. DIAGNOSES: A significant increase in total IgE levels was found in the patient's blood. He had a history of mild chronic allergic rhinitis and slightly intermittent wheezing. However, we found that the child had a hyperallergic reaction to multiple respiratory antigens and had mild pulmonary dysfunction. Finally, colonoscopy with biopsy identified the diagnosis of CC. INTERVENTION: Considering that a respiratory allergic reaction was one of the causes of diarrhea, anti-allergic treatment was given to the child, and his severe diarrhea was soon relieved. Corticosteroid treatment was suggested to the patient, but his parents firmly refused steroid therapy. According to the patient's specific allergic reaction to mites, desensitization treatment was finally chosen for him. OUTCOMES: After 1 year of desensitization for dust mites, the patient's respiratory symptoms improved, total IgE levels decreased, autoantibodies declined, and diarrhea did not reoccur. Colonoscopy with biopsy showed a significant improvement in pathology. CONCLUSION: CC in children is rare, and childhood CC induced by a respiratory allergic reaction has not been previously reported. Therefore, this is a special case of CC in a patient who was cured with anti-allergy treatments and desensitization instead of steroid therapy.

Reduced thiamine binding is a novel mechanism for TPK deficiency disorder.

Thiamine pyrophosphokinase (TPK) converts thiamine (vitamin B1) into thiamine pyrophosphate (TPP), an essential cofactor for many important enzymes. TPK1 mutations lead to a rare disorder: episodic encephalopathy type thiamine metabolism dysfunction. Yet, the molecular mechanism of the disease is not entirely clear. Here we report an individual case of episodic encephalopathy, with familial history carrying a novel homozygous TPK1 mutation (p.L28S). The L28S mutation leads to reduced enzymatic activity, both in vitro and in vivo, without impairing thiamine binding and protein stability. Thiamine supplementation averted encephalopathic episodes and restored the patient's developmental progression. Biochemical characterization of reported TPK1 missense mutations suggested reduced thiamine binding as a new disease mechanism. Importantly, many disease mutants are directly or indirectly involved in thiamine binding. Thus, our study provided a novel rationale for thiamine supplementation, so far the major therapeutic intervention in TPK deficiency.

[Clinical and genetic features of early-onset progressive encephalopathy associated with NAXE gene mutations].

Early-onset progressive encephalopathy is a lethal encephalopathy caused by NAXE gene mutations. This paper reports the clinical and genetic features of a patient with early-onset progressive encephalopathy. A 4-year-old boy admitted to the hospital had repeated walking instability and limb weakness for 2 years. The patient and his elder brother (already dead) had clinical onset at 2 years of age. Both of them showed symptoms such as strabismus, ataxia, reduced muscle tone, delayed development, and repeated respiratory failure after infection. The NAXE gene of the patient showed new compound heterozygous mutations, i.e., c.255 (exon 2) A>T from his mother and c.361 (exon 3) G>A from his father. The NAXE gene encodes an epimerase that is essential for the repair of cellular metabolites of NADHX and NADPHX. This disease is associated with a deficiency of the mitochondrial NAD(P)HX repair system. Patients usually have rapid disease progression. They are also quite likely to have respiratory failure immediately after infection.

Acute myelitis of children with positive anti-GM1 antibody: Case series and literature review.

RATIONALE: To explore the clinical features, treatment, and prognosis of acute myelitis (AM) of children with positive blood anti- ganglioside (GM1) antibodies. PATIENT CONCERNS: Two cases of AM of children with positive anti-GM1 antibody were retrospectively collected and followed up for 6 months. Two cases had positive helicobacter pylori IgG antibody, and Case 2 also had positive mycoplasma IgM antibody. DIAGNOSES: Two cases had typical symptoms of myelitis, abnormal spinal magnetic resonance imaging (MRI), and positive serum anti-GM1 IgM. INTERVENTIONS: They were treated with steroid, immunoglobulin and rehabilitation. OUTCOMES: Symptoms of AM were relieved after treatment. After 6 months of follow-up, case 1 was fully recovered and case 2 was partially recovered. Summarizing previous reports in literature and our 2 cases, AM with positive anti-GM1 antibody can be induced by multiple pathogen infections. About 35.7% were fully recovered, 42.9% had mild sequelae, and 21.4% had severe sequelae. LESSONS: Post-infection immune injury plays an important role in the pathogenesis of AM with positive anti-GM1 antibody. H pylori and Mycoplasma pneumoniae infection may also induce AM with positive anti-GM1 antibody. Screening and treatment of pathogens were required and only 21.4% patients had severe sequelae after treatment.

Therapeutic benefits of ACTH and levetiracetam in STXBP1 encephalopathy with a de novo mutation: A case report and literature review.

RATIONALE: The case report aims to discuss the clinical symptoms and treatment of encephalopathy caused by a novel syntaxin- binding protein 1 (STXBP1) genetic mutation. PATIENT CONCERNS: The patient, a girl, was born at 38+4 weeks of gestation. She had frequent spasm attacks accompanied by obvious psychomotor development retardation since the neonatal period. Genetic screening identified a novel STXBP1 genetic mutation. DIAGNOSES: Early-onset epileptic encephalopathy with STXBP1 mutation. INTERVENTIONS: We adjusted the antiepileptic strategy to oral levetiracetam and topiramate, and intravenous administration of adrenocorticotropic hormone(ACTH) for 2 weeks. Subsequently, prednisone was continued, and gradually reduced and withdrawn over 3 months. OUTCOMES: The treatment was effective with complete control of the epileptic seizures and improvements in the electroencephalogram readings. However, the effects on psychomotor ability were slow and limited. A literature review of STXBP1 mutation cases in which ACTH was administered showed that complete seizure control is observed in 60% of cases, 20% are partially affected, and the remaining 20% show no effect. LESSONS: ACTH and levetiracetam had good therapeutic effects in epilepsy control in this case of de novo STXBP1 mutation. ACTH is an effective drug for early-onset epileptic encephalopathy caused by STXBP1 mutation. However, controlling epilepsy using this therapy does not alter the psychomotor development retardation caused by the STXBP1 mutation.

[Clinical features of Enterococcus faecium meningitis in children].

OBJECTIVE: To summarize the clinical features of Enterococcus faecium meningitis in children. METHODS: The clinical data of nine children with Enterococcus faecium meningitis were analyzed. RESULTS: In all the nine children, Enterococcus faecium was isolated from blood, cerebrospinal fluid, or peripherally inserted central catheters; 6 (67%) patients were neonates, 2 (22%) patients were younger than 6 months, and 1 (11%) patient was three years and four months of age. In those patients, 56% had high-risk factors before onset, which included intestinal infection, resettlement of drainage tube after surgery for hydrocephalus, skull fracture, perinatal maternal infection history, and catheter-related infection. The main symptoms were fever and poor response. In those patients, 22% had seizures; no child had meningeal irritation sign or disturbance of consciousness. The white blood cell count and level of C-reactive protein were normal or increased; the nucleated cell count in cerebrospinal fluid was normal or mildly elevated; the protein level was substantially elevated; the glucose level was decreased. The drug sensitivity test showed that bacteria were all sensitive to vancomycin and the vancomycin treatment was effective. Only one child had the complication of hydrocephalus. CONCLUSIONS: Enterococcus faecium meningitis occurs mainly in neonates and infants. The patients have atypical clinical features. A high proportion of patients with Enterococcus faecium meningitis have high-risk factors. Enterococcus faecium is sensitive to vancomycin.

[Risk Factors and Prognosis of Secondary Epilepsy in Children with Viral Encephalitis].

OBJECTIVES: To investigate the clinical features of viral encephalitis in children at acute stage, and the relationship of these clinical features with post viral encephalitic epilepsy. METHODS: The children with viral encephalitis treated in West China Second University Hospital between January 2010 and January 2014 were enrolled. The clinical features included general conditions, clinical manifestations, video electroencephalogram (VEEG), neuroimaging, virology, prognosis and antiepileptic drugs. The logistic regression model analysis was utilized to analyze the risk factors for the occurrence, bad control, and poor prognosis of post viral encephalitic epilepsy. RESULTS: Total 506 children with viral encephalitis were enrolled. Of these, 58(11.46%)developed epilepsy with a follow-up period more than 1.5 years. The logistic regression analysis showed that the risk factors were repetitive seizures (SB =3.602), detection of clinical seizures in EEG (SB =3.061), status epilepticus (SB =2.711) and mental/behavior disorder (SB =1.850). Among 58 epilepsy cases, 40(74.07%) had favorable seizure control, including 37 cases (92.5%) using no more than two kinds of antiepileptic drugs. With Glasgow Outcome Scale, 24 patients (41.38%) had poor prognosis, including 20 cases of intellectual and psychomotor retardation (83.33%), 3 cases of language disorders (12.50%), 1 case of hearing impairment (4.17%), 3 cases of limb dysfunction (12.50%), 3 cases of mortalities (12.50%). Single factor analysis suggested status epilepticus in acute phase had more chance to poor prognosis, but this was not confirmed by logistic regression analysis. CONCLUSION: The risk factors of post viral encephalitic epilepsy in pediatric patients comprise the mental/behavior disorder, repetitive seizures, status epilepticus, and detection of clinical seizures during VEEG monitoring. The risk factors of poor prognosis remain unclear.

[Clinical Feature in Infants of Breast Feeding Allergy and Its Possible Relation with Gastrointestinal Peptide Change in Breast Milk].

OBJECTIVES: To investigate clinical features in infants of breast milk allergy(BMA), and the possible relationship with the changes of somatostatin (SST) and motilin (MTL) in breast milk. METHODS: Twenty three cases of pure breast feeding infants with allergic gastroenteritis were collected, while another 23 normal infants with pure breast feeding were enrolled as normal controls. Samples of infant stools and breast milk were collected for the measurement of SST and MTL levels detected by by radioimmunity. RESULTS: The levels of SST and MTL in stool samples (pg/mg) were 32.6±8.9, 2.3±3.7 in BMA group and 56.2±12.7, 21.6±4.7 in normal control group, respectively. Those in breast milk (pg/mg) were 236.7±28.9, 159.4±36.7 in BMA group and 412.6±36.7, 216.8±59.7 in normal control group, respectively. All the differences were statistically significant ( P<0.05). In BMA infants, the clinical features were 91.3% (20/23) of diarrhea, 86.9% (21/23) of vomiting, 69.6% (16/23) of hematochezia, 95.7% (22/23) of C-reactive protein (CRP) increasing, 87.0% (20/23) of occult blood in stools, 73.9% (17/23) of neutrophil increasing, 39.1% (9/23) of WBC in stools. CONCLUSIONS: For those infants of breast feeding with persisting and repeated gastrointestinal symptoms, allergy for breast milk should be considered. Deficiency of SST and MTL in breast milk may be a possible cause for food allergy.

[Analysis of brainstem auditory evoked potential in premature infants after perinatal hypoxia].

OBJECTIVE: To examine brainstem auditory evoked potential (BAEP) in preterm infants after perinatal hypoxia within 3 days and 1 month after birth. METHODS: BAEP was studied in 42 preterm infants after perinatal hypoxia within 3 days and 1 month after birth, and was compared with those in preterm without any major perinatal problems. RESULTS: The latencies of wave V and the interpeak intervals of III-V and I-V in BAEP of hypoxia preterm infants differed significantly from those in the control with 3 days after birth. One month later, the latencies of wave and the interpeak intervals in BAEP of hypoxia infants were improved, and there were no significant differences between two groups. CONCLUSION: Central auditory function in preterm infants will be damaged by perinatal hypoxia, which must be taken into account even the damage could be improved in 1 month after birth.

[Research on cells ablation characters by laser plasma].

The study on the mechanism of laser ablated cells is of importance to laser surgery and killing harmful cells. Three radiation modes were researched on the ablation characteristics of onion epidermal cells under: laser direct irradiation, focused irradiation and the laser plasma radiation. Based on the thermodynamic properties of the laser irradiation, the cell temperature rise and phase change have been analyzed. The experiments show that the cells damage under direct irradiation is not obvious at all, but the focused irradiation can cause cells to split and moisture removal. The removal shape is circular with larger area and rough fracture edges. The theoretical analysis found out that the laser plasma effects play a key role in the laser ablation. The thermal effects, radiation ionization and shock waves can increase the deposition of laser pulses energy and impact peeling of the cells, which will greatly increase the scope and efficiency of cell killing and is suitable for the cell destruction.

Clinical application of laparoscopic spleen-preserving operation in traumatic spleen rupture.

OBJECTIVE: To evaluate the effect of laparoscopic spleen-preserving operation for traumatic spleen rupture. METHODS: From 1997 to 2003, 15 cases of traumatic spleen rupture were treated with laparoscopic spleen-preserving operation in our hospital. Nine cases had operation history in the middle and lower abdomen. ZT binding, electrocoagulation, fibrin and gelfoam tamping and suture repairing were used in patients with spleen rupture of grade I and grade II. Combined hemostasis was used for spleen rupture of grade III. RESULTS: All patients did not need laparotomy during operation and no postoperative bleeding occurred. They were all cured and followed up for 3-12 months. Determination of immunoglobulins after operation showed normal, and spleen ultrasonic examination, CT and body state evaluations were all satisfactory. CONCLUSIONS: Laparoscopy in the management of spleen trauma can be used in confirmed diagnosis and in determining the degree of spleen injury. For patients with stable vital signs laparoscopic spleen-preserving operation can be used. The laparoscopic spleen-preserving operation is safe in the treatment of traumatic spleen rupture.

[Age difference of the activation of apoptotic cascade reaction following LiCl-pilocarpine status epilepticus].

OBJECTIVE: To explore the age character of the activity of Caspase 3 and neuron death induced by LiCl-pilocarpine status epilepticus. METHODS: LiCl-pilocarpine was injected into healthy infant rats (19 days) and adult rats (2-3 months) subcutaneously and intra-abdominally to evoke status epilepticus (SE). First, the age difference of the seizure was used to measure the sensitivity of seizure. Second, the dynamic features of the apoptotic neurons and the activity of Caspase 3 at 15, 30 min and 1, 2, 4, 8 hours after SE respectively were investigated by TUNEL, flow cytometry and fluorospectrophotometry. RESULTS: (1) The average duration from the injection to seizure was (13.3 +/- 5.63) min in infant rats, and (22.5 +/- 5.66) min in adult rats. (2) The proportion of the 4th or 5th degree of severity at onset of seizure was 68% in infant rats and 18% in adult rats. (3) Although the count of died neurons (in the CA3 of hippocampus, dentate gyrus and cortex of temporal lobe) was physiologically higher in normal infant rats than in adult rats, the count of positive neurons by TUNEL stain in mature brain (524 +/- 26) remarkably increased and exceeded that in premature brain (465 +/- 26) at 30 min after SE. Although continuously observed until 8 hours after SE, the count of apoptotic neurons in mature brain was also remarkably higher than that in infant brain. Change of neurons in apoptotic early events detected by flow cytometry was the same as the result of TUNEL. (4) The increasing proportion of activity of Caspase 3 after SE for 30 min in adult rats remarkably exceeded that in infant rats; it was 0.10 +/- 0.07 in adult rats and 0.003 +/- 0.04 in infant rats. The difference between the infant rats (0.39 +/- 0.20) and adult rats (0.10 +/- 0.20) increased after SE for 2 hours. CONCLUSION: A mechanism of inhibiting apoptotic process in premature brain during SE for the protection against brain damage was well reconfirmed by different animal SE models induced by lithium-pilocarpine. It was indicated that the protective mechanism against brain damage in premature brain could be presented in most severe seizures of different types. This protective mechanism could act on the apoptotic occurrence in the earlier period before the activation of Caspase cascade reaction.