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Purpose: Despite the rising incidence of differentiated thyroid cancer (DTC), mortality rates have remained relatively low yet crucial for effective patient management. This study aims to develop a deep neural network capable of predicting mortality in patients with differentiated thyroid cancer., Methods: Leveraging data from the Surveillance, Epidemiology, and End Results (SEER) database, we developed Thy-DAMP (Deep Artificial Neural Network Model for Prediction of Thyroid Cancer) to forecast mortality in DTC patients. The dataset comprised demographic, histologic, and staging information. Following data normalization and feature encoding, the dataset was partitioned into training, testing, and validation subsets, with model hyperparameters fine-tuned via cross-validation., Results: Among the 63,513 patients, the mean age was 48.22 years (SD = 14.8), with 77.32% being female. Papillary carcinoma emerged as the predominant subtype, representing 62.94% of cases. The majority presented with stage I disease (73.96%). Thy-DAMP demonstrated acceptable performance metrics on both the test and validation sets. Sensitivity was 83.24% (95% CI 76.95-88.40%), specificity was 93.53% (95% CI 93.01-94.02%), and accuracy stood at 93.33% (95% CI 92.82-93.83%). The model exhibited a positive predictive value of 19.76% (95% CI 18.20-21.42%) and a negative predictive value of 99.66% (95% CI 99.53-99.75%). Additionally, Thy-DAMP demonstrated a positive likelihood ratio of 12.86 (95% CI 11.62-14.23), a negative likelihood ratio of 0.18 (95% CI 0.13-0.25), and an area under the receiver operating characteristic curve (AUROC) of 0.95. The model was externally validated on a separate dataset with nearly identical performance., Conclusion: Thy-DAMP showcases considerable promise in accurately predicting mortality in DTC patients, leveraging limited set of patient data., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: The ongoing outbreak of the respiratory disease coronavirus disease 2019 (COVID-19) is currently presenting a major global health threat. This pandemic is unprecedented in recent human history. The objective of this study was to examine the relationship between cycle quantitation (Cq) and laboratory parameters in COVID-19 patients, aiming to determine if Cq levels can provide valuable insights into the COVID-19 disease., Methods: This study involved 234 participants who were divided into case and control groups. Real-time PCR tests were used to diagnose COVID-19 cases in the study participants. Blood tests, including complete blood count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), lactate dehydrogenase (LDH), D-dimer, IgG, and IgM, were also conducted. Statistical analysis was performed using SPSS 22 software., Results: The findings showed that COVID-19-positive cases had significantly higher levels of the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), D-dimer, ESR, CRP, and LDH compared to normal cases. Additionally, the case group had significantly lower lymphocyte and platelet counts. There was a statistically significant positive correlation between Cq levels and lymphocyte count (r = .124, p = .014). Conversely, there was a statistically significant inverse correlation between Cq levels and NLR (r = -.208, p = .017). Furthermore, the evaluation of hematological, inflammatory, and biochemical indexes in COVID-19 patients using the receiver-operating characteristics curve demonstrated statistically appropriate sensitivity and specificity., Conclusion: Our outcomes indicated a significant association between Cq levels and PLR, NLR, D-dimer, CRP, and ESR in COVID-19 patients. Consequently, including the report of laboratory parameters alongside Cq values offers a promising prognosis., (© 2024 The Author(s). Immunity, Inflammation and Disease published by John Wiley & Sons Ltd.)

Aim: This study aimed to investigate the role of AmpC enzymes in carbapenem resistance among AmpC/extended-spectrum β-lactamase (ESBL)-producing clinical isolates of Escherichia coli and Klebsiella spp. Methods: Fifty-six bacterial strains that were AmpC producers were examined. The antibiotic susceptibility test was performed by the disk diffusion and E-test. The prevalence of the plasmid carbapenemase was determined using PCR. Results: The resistance to meropenem in the AmpC + /ESBL + group was 64%, higher than that reported for the AmpC - /ESBL + group. Ten isolates of the carbapenem-resistant AmpC producers were negative for carbapenemase-encoding genes. Conclusion: Carbapenem resistance among AmpC-producing isolates with negative results for carbapenemase-encoding genes potentially demonstrates the role of AmpC enzymes among these isolates.

Loop-mediated isothermal amplification is a promising candidate for the rapid detection of Mycobacterium tuberculosis . However, the high potential for carry-over contamination is the main obstacle to its routine use. Here, a closed tube LAMP was intended for the visual detection of Mtb to compare turbidimetric and two more favorable colorimetric methods using calcein and hydroxy naphthol blue (HNB). Additionally, a less studied dye (i.e., eriochrome black T (EBT)) was optimized in detail in the reaction for the first time. Mtb purified DNA and 30 clinical specimens were used to respectively determine the analytical and diagnostic sensitivities of each method. The turbidimetric method resulted in the best analytical sensitivity (100 fg DNA/reaction), diagnostic sensitivity and specificity (100%), and time-to-positivity of the test (15 min). However, this method is highly prone to subjective error in reading the results. Moreover, HNB-, calcein-, and EBT-LAMP could respectively detect 100 fg, 1 pg, and 1 pg DNA/reaction (the analytical sensitivities) in 30, 15, and 30 min, while the diagnostic sensitivity and specificity were respectively 93.3% and 100% for them all. Interestingly, EBT-LAMP showed the lowest potential for subjective error in reading the results. This report helps judiciously choose the most appropriate visual method, taking a step forward toward the field applicability of LAMP for the detection of Mtb, particularly in resource-limited settings.

Little is known about the role of diet in the risk of invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) of the breast, the most common histological subtypes of breast cancer (BC). This is because, the majority of studies on the association of diet and the risk of BC are focused on single food items, and studies considering the overall diet in terms of dietary patterns are limited. Also, the potential heterogeneity in the impact of Western diet (WD) on histological subtypes of BC is not established. This, the age-frequency-matched case-control study included 1009 incident BC cases and 1009 healthy controls. The required data was obtained from the patients' medical files and interviews using a previously validated researcher-designed questionnaire for collecting data on socio-economic and anthropometric statuses and a valid food frequency questionnaire (FFQ) to measure the participants' dietary intake. We used multinomial logistic regression, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. A positive and significant association was observed between higher adherence to a WD and risk of IDC (OR comparing highest with the lowest tertile: 2.45, 95% CI 1.88, 3.17; p-trend < 0.001), whereas no significant association was observed between adherence to the WD and the risk of ILC (OR comparing highest with the lowest tertile: 1.63, 95% CI 0.63, 3.25) (p for heterogeneity = 0.03). The results of an analysis stratified by menopausal status suggested a similar pattern. We provided evidence that adherence to a WD raises the risk of IDC, but not ILC, suggesting different etiological mechanisms for IDC and ILC., (© 2022. The Author(s).)

Is population-level heterogeneity a reflection of distinct subpopulations, exhibiting different metabolic functions, or dynamic metabolism of individuals within the population? This fascinating question has remained a subject of great interest in studying metabolic specialization in microorganisms. The Crabtree effect - i.e., the ability of some microorganisms to switch from respiration to fermentation in the presence of oxygen - is an appropriate case study to address the aforementioned question. Game-theoretical approaches have been routinely used to examine and explain the way a microorganism, such as yeast, would switch between the two ATP-producing pathways, i.e., respiration and fermentation. Here we attempt to explain the switch between respiration and fermentation in yeast by constructing a simple metabolic switch. We then utilize an individual-based model, in which each individual is equipped with all the relevant chemical reactions, to see how cells equipped with such metabolic switch would behave in different conditions. We further investigate our proposed metabolic switch using the game-theoretical approach. Based on this model, we postulate that the population-level metabolic heterogeneity in microorganisms can simply arise from individuals utilizing a mixed strategy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, a series of mono- and diallylphenol derivative were designed, synthesized, and evaluated as potential human 15-lipoxygenase-1 (15-hLOX-1) inhibitors. Radical scavenging potency of the synthetic allylphenol derivatives was assessed and the results were in accordance with lipoxygenase (LOX) inhibition potency. It was found that the electronic natures of allyl moiety and para substituents play the main role in radical scavenging activity and subsequently LOX inhibition potency of the synthetic inhibitors. Among the synthetic compounds, 2,6-diallyl-4-(hexyloxy)phenol (42) and 2,6-diallyl-4-aminophenol (47) showed the best results for LOX inhibition (IC 50 = 0.88 and 0.80 μM, respectively)., (© 2020 Wiley Periodicals, LLC.)

Objective: The production of β-lactamase enzymes such as AmpC β-lactamases and extended-spectrum β-lactamases (ESBLs) is among the main mechanisms for resistance to expanded-spectrum cephalosporins. The present study was conducted to investigate the prevalence and molecular epidemiology of plasmid-mediated AmpC beta (β)-lactamase in ESBL co-producing Escherichia coli (E. coli) and Klebsiella spp. (Klebsiella pneumoniae and Klebsiella oxytoca) clinical isolates in the northeast of Iran., Methods: A total of 602 E. coli and Klebsiella spp. clinical isolates were collected from three hospitals in Mashhad (northeast of Iran). A combination disk test (CDT) was performed for the phenotypic detection of ESBLs. Screening for the detection of AmpC β-lactamases was performed by a susceptibility test to a cefoxitin disc among ESBL producing isolates. A confirmatory test for AmpC β-lactamases was performed using the Mast® D68C test. Identification of plasmid-mediated AmpC cluster genes was done by multiplex polymerase chain reaction (PCR)., Results: Among 336 ESBL-producing strains, 230 (68.4%) isolates were resistant to cefoxitin. Results of the Mast® D68C test showed that 30% (69/230) of cefoxitin-resistant isolates simultaneously exhibited ESBL and AmpC activity and 22% (51/230) of isolates probably showed multi-drug resistant (MDR) phenotype. Results of multiplex PCR among ESBL-positive isolates showed that, 16.7% (56/336) of isolates were positive for plasmid-borneampC cluster genes, and CMY (38%) was the most frequent genotype of plasmid mediated AmpC., Conclusion: Findings of the study revealed that an increase in the prevalence of ESBL and AmpC co-producer in E. coli and Klebsiella spp. strains may become an important public health issue. Therefore, there is a vital need for surveillance of spread of these clinical isolates., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Reducing the complex behavior of living entities to its underlying physical and chemical processes is a formidable task in biology. Complex behaviors can be characterized as decision making: the ability to process the incoming information via an intracellular network and act upon this information to choose appropriate strategies. Motility is one such behavior that has been the focus many modeling efforts in the past. Our aim is to reduce the chemotactic behavior in Escherichia coli to its molecular constituents in order to paint a comprehensive and end-to-end picture of this intricate behavior. We utilize a hierarchical approach, consisting of three layers, to achieve this goal: at the first level, chemical reactions involved in chemotaxis are simulated. In the second level, the chemical reactions give rise to the mechanical movement of six independent flagella. At the last layer, the two lower layers are combined to allow a digital bacterium to receive information from its environment and swim through it with verve. Our results are in concert with the experimental studies concerning the motility of E.coli cells. In addition, we show that our detailed model of chemotaxis is reducible to a non-homogeneous Markov process., Competing Interests: Declaration of Competing Interest The authors declare that we do not have competing interests., (Copyright © 2020. Published by Elsevier Ltd.)

The emergence of phenotypic diversity in a population of cells and their arrangement in space and time is one of the most fascinating features of living systems. In fact, understanding multicellularity is unthinkable without explaining the proximate and the ultimate causes of cell differentiation in time and space. Simpler forms of cell differentiation can be found in unicellular organisms, such as bacterial biofilm, where reversible cell differentiation results in phenotypically diverse populations. In this manuscript, we attempt to start with the simple case of reversible nongenetic phenotypic to construct a model of differentiation and pattern formation. Our model, which we refer to as noise-driven differentiation (NDD) model, is an attempt to consider the prevalence of noise in biological systems, alongside what is known about genetic switches and signaling, to create a simple model which generates spatiotemporal patterns from bottom-up. Our simulations indicate that the presence of noise in cells can lead to reversible differentiation and the addition of signaling can create spatiotemporal pattern., Competing Interests: The authors have declared that no competing interests exist.

We investigate both analytically and by computer simulations the ensemble- and time-averaged, nonergodic, and aging properties of massive particles diffusing in a medium with a time dependent diffusivity. We call this stochastic diffusion process the (aging) underdamped scaled Brownian motion (UDSBM). We demonstrate how the mean squared displacement (MSD) and the time-averaged MSD of UDSBM are affected by the inertial term in the Langevin equation, both at short, intermediate, and even long diffusion times. In particular, we quantify the ballistic regime for the MSD and the time-averaged MSD as well as the spread of individual time-averaged MSD trajectories. One of the main effects we observe is that, both for the MSD and the time-averaged MSD, for superdiffusive UDSBM the ballistic regime is much shorter than for ordinary Brownian motion. In contrast, for subdiffusive UDSBM, the ballistic region extends to much longer diffusion times. Therefore, particular care needs to be taken under what conditions the overdamped limit indeed provides a correct description, even in the long time limit. We also analyze to what extent ergodicity in the Boltzmann-Khinchin sense in this nonstationary system is broken, both for subdiffusive and superdiffusive UDSBM. Finally, the limiting case of ultraslow UDSBM is considered, with a mixed logarithmic and power-law dependence of the ensemble- and time-averaged MSDs of the particles. In the limit of strong aging, remarkably, the ordinary UDSBM and the ultraslow UDSBM behave similarly in the short time ballistic limit. The approaches developed here open ways for considering other stochastic processes under physically important conditions when a finite particle mass and aging in the system cannot be neglected.

It is quite generally assumed that the overdamped Langevin equation provides a quantitative description of the dynamics of a classical Brownian particle in the long time limit. We establish and investigate a paradigm anomalous diffusion process governed by an underdamped Langevin equation with an explicit time dependence of the system temperature and thus the diffusion and damping coefficients. We show that for this underdamped scaled Brownian motion (UDSBM) the overdamped limit fails to describe the long time behaviour of the system and may practically even not exist at all for a certain range of the parameter values. Thus persistent inertial effects play a non-negligible role even at significantly long times. From this study a general questions on the applicability of the overdamped limit to describe the long time motion of an anomalously diffusing particle arises, with profound consequences for the relevance of overdamped anomalous diffusion models. We elucidate our results in view of analytical and simulations results for the anomalous diffusion of particles in free cooling granular gases.

In many social complex systems, in which agents are linked by non-linear interactions, the history of events strongly influences the whole network dynamics. However, a class of "commonly accepted beliefs" seems rarely studied. In this paper, we examine how the growth process of a (social) network is influenced by past circumstances. In order to tackle this cause, we simply modify the well known preferential attachment mechanism by imposing a time dependent kernel function in the network evolution equation. This approach leads to a fractional order Barabási-Albert (BA) differential equation, generalizing the BA model. Our results show that, with passing time, an aging process is observed for the network dynamics. The aging process leads to a decay for the node degree values, thereby creating an opposing process to the preferential attachment mechanism. On one hand, based on the preferential attachment mechanism, nodes with a high degree are more likely to absorb links; but, on the other hand, a node's age has a reduced chance for new connections. This competitive scenario allows an increased chance for younger members to become a hub. Simulations of such a network growth with aging constraint confirm the results found from solving the fractional BA equation. We also report, as an exemplary application, an investigation of the collaboration network between Hollywood movie actors. It is undubiously shown that a decay in the dynamics of their collaboration rate is found, even including a sex difference. Such findings suggest a widely universal application of the so generalized BA model.

Background: Addicted patients have innate tolerance to local anesthetics in both neuraxial and peripheral blocks. Dexmedetomidine (Dex) is a highly selective α2 adrenergic receptor agonist used as additive to increase quality and duration of peripheral nerve blocks., Objectives: The current study aimed to compare the effect of dexmedetomidine and fentanyl additives on bupivacaine to prolong the duration of block and minimizing side effects., Patients and Methods: Patients were candidates for elective surgery less than three hours of lower abdomen or lower extremities surgeries. Patients were randomly allocated to receive dexmedetomidine 5 µg added to 12.5 mg (2.5 mL) of 0.5% hyperbaric bupivacaine (DEX group), or 25 µg (0.5 mL) fentanyl added to 12.5 mg (2.5 mL) of 0.5% hyperbaric bupivacaine (F group) or only 12.5 mg of 0.5% hyperbaric bupivacaine. Data were recorded based on sensory block. Motor block was tested using modified Bromage scale every 30 minutes until the end of block. Time to return of sensory block to 4 dermatomes below and time to return of Bromage scale to 0 were recorded. All vital measurements (oxygen saturation, heart rate, electrocardiogram, and non-invasive blood pressure) were performed at 0, 30, 60, 90, 120 and 180 minutes in all three groups of the study. Group DEX received dexmedetomidine additive and group F received fentanyl additive and group C (control) received normal saline., Results: Totally, 84 patients were randomly divided into three groups of 28 patients. Onset of sensory block in DEX group was significantly lower than those of fentanyl (P = 0.012) and control groups (P = 0.001). Duration of sensory block was significantly longer in DEX group compared to Fentanyl (P = 0.043) and control (P = 0.016) groups. Duration of motor block in the DEX group was significantly longer than those of the fentanyl (P = 0.014) and control groups. Heart rate and mean arterial pressure were significantly higher in the DEX group at 30, 60, 90,120, and 180 minutes compared to those of the other two groups (P < 0.05)., Conclusions: Dexmedetomidine added to bupivacaine in spinal anesthesia is more effective to increase duration of block, providing more appropriate sedation and less postoperative pain scale and post-operative nausea and vomiting (PONV) compared to fentanyl additive.

Background: Pathogenic mycobacteria are a major cause of human morbidity and mortality. Mycobacterium tuberculosis is an etiological agent of human tuberculosis (TB). Designing new vaccines, including DNA vaccines, may be a useful strategy for preventing TB., Objectives: The purpose of this study was to design and construct an eukaryotic expression vector containing M. tuberculosis., Materials and Methods: Genomic DNA of M. tuberculosis H37Rv cultured on Lowenstein Jensen medium was extracted, and cfp10 was amplified by PCR. After digesting the PCR product and the plasmid, the cfp10 fragment was ligated into the vector pcDNA3.1 (+). Correct insertion was confirmed by colony PCR, restriction enzyme digestion, and sequencing., Results: Electrophoresis of the PCR product on gel showed a 303-bp target fragment. Colony PCR, restriction enzyme digestion, and Sequencing methods confirmed the accuracy of the gene cloning. Colony PCR and restriction enzyme digestion confirmed the cloning., Conclusions: Cloning of cfp10 of M. tuberculosis into an eukaryotic expression vector was performed successfully. We propose this recombinant plasmid for inducing immunity in animal models in future studies. This recombinant vector can also be used in the construction of fusion proteins.

Advances in DNA sequencing have greatly enhanced the molecular epidemiology studies. In order to assess evolutionary and phylogenetic relation of Mycobacterium tuberculosis isolates several gene targets were evaluated. In this study, appropriate fragments of 5 highly variable genes (rpsL, mprA, lipR, katG, and fgd1 genes) were sequenced. The sequence data were analyzed with neighbor-joining method using mega and Geneious software. The phylogenetic trees analyzes revealed that the discriminatory power of lipR is much stronger than that observed in the other genes. lipR could distinguish between more clinical isolates. Therefore, lipR is a promising target for sequence analyzes of M. tuberculosis.

Class A and D β-lactamases are the main causes of resistance against β-lactam antibiotics, especially the penam group, in Staphylococcus aureus. On the basis of the potentiator property of ethanolic extracts of Ferula szowitsiana root on penicillin, MIC values observed for resistant S. aureus, the main naturally occurring compounds in these extracts, auraptene, umbelliprenin and galbanic acid, were evaluated for β-lactamase inhibitory activity. Amongst them auraptene showed the most potent inhibitory activity (IC50=21±1.5 μM) toward class A β-lactamase, whereas no inhibition was observed for class D β-lactamase. To obtain the structure activity relationship of the mentioned compounds and rationalize the enzyme inhibitory results, docking analysis was performed for both groups of β-lactamases. Docking analysis showed that the compounds have 100-500-fold lower bonding affinity toward the class D β-lactamase than toward the class A enzyme.

15-Lipoxygenases are one of the nonheme iron-containing proteins with ability of unsaturated lipid peroxidation in animals and plants. The critical role of the enzymes in formation of inflammations, sensitivities and some of cancers has been demonstrated in mammalians. Importance of the 15-lipoxygenases leads to development of mechanistic studies, products analysis and synthesis of their inhibitors. In this work new series of the 3-allyl-4-allyoxyaniline amides and 3-allyl-4-prenyloxyaniline amides were designed, synthesized and their inhibitory potency against soybean 15-lipoxygenase were determined. Among the synthetic amides, 3-allyl-4-(farnesyloxy)-adamantanilide showed the most potent inhibitory activity by IC(50) value of 0.69 μM. SAR studies showed that in spite of prenyl length increases, the effects of the amide size and its electronic properties on the inhibitory potency became predominant. The SAR studies was also showed that the orientation of allyl and prenyloxy moieties toward Fe core of the SLO active site pocket is the most suitable location for enzyme inhibition., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A case of histologically proven benign choroid plexus papilloma of the third ventricle in a 4-month-old male child is reported. The clinical symptoms and the neuroradiologic findings were those of a supratentorial hydrocephalus. A shunting procedure was performed after refusal by the family of a direct surgical approach. Subsequently there was a four- to fivefold increase in volume of this tumor in less than 4 months under decreased cerebrospinal fluid pressure. The purpose of this report is first to add a case to 27 cases of papilloma of the choroid plexus of third ventricle reported in the medical literature. Secondly to underline a possible influence of intraventricular pressure on the growth of a histologically benign intraventricular papilloma. Subsequently, the question of radiation therapy may be raised, if total removal of the papilloma is not obtained, especially in view of decreased cerebrospinal fluid pressure provided by the previous shunting procedure.

The authors report on an autopsy-proven case of multifocal widespread radionecrosis involving both cerebral hemispheres and masquerading as tumor dissemination on a CT scan done 13 months after complete resection of an oligodendroglioma followed by radiation therapy. This case demonstrates that radiation damage may be present in a CT scan as a multifocal, disseminated lesion. Since the survival of brain-tumor patients who have undergone radiation therapy is prolonged by aggressive therapy, the incidence and variability of radiation-induced complications in such cases is likely to increase. For similar reasons, the radionecrosis in such cases should be taken into consideration. A short review of the CT scan findings and diagnostic and therapeutic considerations in a case of widespread radionecrosis is presented. The need for appropriate diagnosis and subsequent life-saving management is emphasized.

In a clinical trial, 10 patients with malignant gliomas underwent partial resection of their tumors and were treated by intraarterial 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) chemotherapy. The drug was given at least 1 month after the completion of postoperative radiotherapy in total doses of 270-280 mg/m2 in two sessions separated by a 48-hour interval (the two sessions with interval were equal to one course). This therapy was repeated every 8-10 weeks. Four patients had three courses and the other six patients had two courses of chemotherapy. This therapy was the only antitumor chemotherapy for this group of patients. Our preliminary results demonstrate the safety of this new procedure and suggest that intraarterial BCNU chemotherapy may be more effective, and has a better tolerance and less toxicity, than intravenous BCNU chemotherapy. Furthermore, it was demonstrated that, in the case of one patient, higher antitumor activity resulted from intraarterial BCNU chemotherapy as compared to intravenous BCNU therapy.

Recurrent symptoms or signs during or after therapeutic brain irradiation may be due to the progression of the irradiated tumour, necrosis of normal brain tissue, necrosis of tumour, or all three of these. We have studied 12 patients with pathologically proven radiation-induced damage of normal brain tissue. All patients were exposed to a therapeutic range of radiation for an intra or extracranial tumour. Seven patients were exposed to 280 to 300 rads per day, three times weekly to a total dose of 4500 to 6000 rads (fractionated). Five patients received 750 to 850 rads per day, on days 1, 3, 21 and 23 (split-course). The diagnosis of radiation-induced brain lesions is difficult. CT scan is the most informative diagnostic procedure. The various patterns of radiation-induced brain lesions on CT are nonspecific. However where there is sufficient clinical data suggesting radiation-induced brain lesions, and a good correlation between CT abnormalities and the maximum delivered dose, on dose distribution maps of the brain exposed to a high cumulative radiation dose, the diagnosis may be accepted. The time interval between the end of radiation therapy and the occurrence of radiation-induced lesions was shorter in the patient group exposed to a split-course therapy (median time: 9.6 months) as opposed to the patient group exposed to a fractionated radiation (median time: 45 months). Pathologically the lesions corresponded to either a demyelinated area within the white matter with minimal vasculopathy or an area of coagulation necrosis with varying degrees of necrosis, delamination or hyalinosis of small blood vessels.(ABSTRACT TRUNCATED AT 250 WORDS)

A retrospective study of 72 consecutive and nonrandomized patients with malignant glial tumors is presented. The influence of age, sex, location of tumor, initial presenting symptoms, symptomatic preoperative interval, reoperation, extent of tumor removal, histological subtype of tumor, lymphocyte infiltration, and different treatments upon survival time has been evaluated and statistically analyzed. Age was inversely associated with survival with a strong statistical significance (p = 0.0001). Headache was the most common (67%) initial symptom; aphasia and seizure were both present in 45.3% of patients. Initial presenting symptoms had no effect upon survival. Parietal lobe and lymphocyte infiltration had marginally negative effects upon survival (p = 0.097 and p = 0.10 respectively). The amount of tumor removal was marginally associated with an improved survival (p = 0.07). Radiation therapy was strongly associated with an improved survival time (p = 0.0007). The addition of chemotherapy did not affect the survival (perhaps reflecting the small number of patients and inadequate chemotherapy). There was an obvious beneficial effect of reoperation upon survival time, if the patient lived and underwent reoperation later than 16 months after the initial operation (slow-growing tumor). Although median and mean survival times (10 and 20.34 months respectively, SD 7.45 months) were similar to most series reported, our rates of survival (20%, 12.5%, and 7.5% at 2, 3, and 5 years, respectively) were notably higher.

The biopsy specimens of 342 patients with malignant glioma were evaluated to determine the extent and prognostic significance of round cell infiltration within these representative tissues: (a) tumor, (b) peritumoral, (c) hypervascular, (d) necrotic, and (e) normal tissue. Thirty-six percent of all biopsy specimens showed at least one tissue area with round cell infiltration. Patients in age groups 0 to 25 years and 71 years and older tended to show less round cell infiltration than did patients 41 to 55 years old. The presence of round cell infiltration in tissue was associated with a poor prognosis. Patients showing any infiltration had mean survival times of 8.4 months as opposed to 11.9 months for those showing no infiltration. The relationship between round cell infiltration and poor prognosis is true, irrespective of postoperative therapy, sex, and age.

The microsurgical anatomy and related techniques of a modified anterolateral transthoracic approach to the thoracic disc space is presented. This procedure was performed on at least three thoracic levels of 12 cadavers within a few hours after death. Such an approach allows a safe decompression of the spinal cord and roots under full visual control. There is minimal risk to radiculomedullary vessels, minimal osteoligamental resection, and no compromise of stability of the spinal column. Therefore, this procedure does not require surgical stabilization of the spinal column, postoperative bracing, or prolonged bed rest. The difference between this approach and anterolateral transthoracic, posterolateral, and transpedicular approaches is discussed.