Building a pathway to recovery: Targeting ECM remodeling in CNS injuries.

Extracellular matrix (ECM) is a complex and dynamic network of proteoglycans, proteins, and other macromolecules that surrounds cells in tissues. The ECM provides structural support to cells and plays a critical role in regulating various cellular functions. ECM remodeling is a dynamic process involving the breakdown and reconstruction of the ECM. This process occurs naturally during tissue growth, wound healing, and tissue repair. However, in the context of central nervous system (CNS) injuries, dysregulated ECM remodeling can lead to the formation of fibrotic and glial scars. CNS injuries encompass various traumatic events, including concussions and fractures. Following CNS trauma, the formation of glial and fibrotic scars becomes prominent. Glial scars primarily consist of reactive astrocytes, while fibrotic scars are characterized by an abundance of ECM proteins. ECM remodeling plays a pivotal and tightly regulated role in the development of these scars after spinal cord and brain injuries. Various factors like ECM components, ECM remodeling enzymes, cell surface receptors of ECM molecules, and downstream pathways of ECM molecules are responsible for the remodeling of the ECM. The aim of this review article is to explore the changes in ECM during normal physiological conditions and following CNS injuries. Additionally, we discuss various approaches that target various factors responsible for ECM remodeling, with a focus on promoting axon regeneration and functional recovery after CNS injuries. By targeting ECM remodeling, it may be possible to enhance axonal regeneration and facilitate functional recovery after CNS injuries.

Capillary leak syndrome due to Russell's viper envenomation-A doomy presage for treating clinician.

Russell's viper envenomation is a major challenge to physicians providing intensive care due to diverse presentations and dismal outcomes. The venom can cause idiopathic systemic capillary leak syndrome manifesting with bilateral parotid swelling, hemoconcentration, and refractory shock. Physicians' awareness about this presentation is lacking. Delayed recognition of this syndrome leads to fatalities despite providing the best possible care. We hereby report a fatal case of Daboia russelii bite presenting as capillary leak syndrome. The aim is to create awareness among tropical physicians who are primary caregivers to these victims.

The advent of ECMO and pumpless extracorporeal lung assist in ARDS.

Despite advances in critical care facilities and ventilation therapies acute respiratory distress syndrome (ARDS) is associated with high mortality rates. The condition can stem from a multitude of causes including pneumonia, septicemia and trauma ultimately resulting in ARDS. ARDS is characterized by respiratory insufficiency with severe hypoxemia or hypercapnia. The treatment strategy depends on the knowledge of the underlying disease. But lung-protective ventilation with adjusted positive end-expiratory pressure remains the most effective therapeutic tool despite advances in prone positioning, inhalation of nitric oxide and the use of steroids. Newer modalities including extracorporeal membrane oxygenation (ECMO) and pumpless extracorporeal lung assist (PECLA) are being increasingly introduced in critical care settings as rescue therapies in patients who fail to respond to conservative measures. We describe here the introduction and advances of both ECMO and PECLA in the management of ARDS.

Generation of high-energy femtosecond pulses in multimode-core Yb-fiber chirped-pulse amplification systems.

220-fs pulses with energies of ~100microJ have been generated by use of two different configurations of diode-pumped Yb-fiber chirped-pulse amplification systems. Energy scaling was demonstrated with 25-microm -core diameter fibers, in which stable diffraction-limited output (M(2)~1.1) was achieved. A two-stage fiber-amplifier system produced average powers of up to 5.5 W at ~1- MHz pulse-repetition rate. A double-pass configuration provided 53-dB gain in a single Yb-fiber amplifier stage, thus eliminating the necessity for multiple amplification stages as well as the need for using polarization-preserving fibers.

Advanced laparoscopy: "the next generation". The adrenal, kidney, spleen, pancreas, and liver.

Following the rapid acceptance of laparoscopic cholecystectomy, a few adventurous surgeons "dared to boldly go where no one had gone before." They sought to achieve the same reduction in morbidity while accomplishing the same surgical goals. This paper will briefly review the current status of minimal access surgery for the solid organs of the abdomen. It will focus on the indications, risks, limitations, and on the balance between the trauma of access and the trauma of the procedure itself. As new techniques and equipment emerge and experience and data are accumulated, this balance may shift. Some of these procedures are in their infancy while others are rapidly becoming the new "Gold Standard".

High-energy femtosecond pulse amlification in a quasi-phase-matched parametric amplifier.

A new type of solid-state femtosecond amplifier is demonstrated that is based on quasi-phase-matched parametric amplification. Such gain media are different from conventional solid-state amplifiers in that their amplification bandwidths and pump and signal wavelengths can be engineered. Furthermore, high gain is characteristic of parametric amplification, permitting extraction of high energies without the need to resort to multiple-pass configurations. We report a parametric chirped pulse amplification system in which femtosecond pulses from a mode-locked Er-doped fiber laser system are amplified to 1-mJ energies in a single pass by use of a 5-mm-long periodically poled LiNbO(3) (PPLN) crystal. This amplifier is pumped by 5-mJ and 0.5-ns pulses at 786 nm, demonstrating that limitations associated with a low optical-damage threshold for long pump pulses can be overcome because of the high nonlinearity of PPLN and that relatively simple Q -switched lasers can be used with such parametric amplifiers.

Frequency doubling of femtosecond erbium-fiber soliton lasers in periodically poled lithium niobate.

We report efficient frequency doubling of passively mode-locked femtosecond erbium-fiber lasers. Quasi-phase-matched second-harmonic generation in periodically poled lithium niobate is used to generate 8.1 mW of 190-fs (FWHM), 90-pJ pulses at 777 nm with a conversion efficiency greater than can be obtained with existing birefringently phase-matched nonlinear materials. A dispersion-compensation-free soliton oscillator generating transform-limited 230-fs (FWHM) pulses at 1554 nm is used as a pump laser.

Alexandrite-pumped alexandrite regenerative amplifier for femtosecond pulse amplification.

We demonstrate a regenerative amplif ier incorporating alexandrite as the gain medium that is pumped by an alexandrite laser. Temperature-altered gain permitted the 728-nm alexandrite pump laser, operating at room temperature, to pump a 780-800-nm alexandrite laser that was maintained at elevated temperatures. 200-fs pulses from a Ti:sapphire oscillator were amplif ied to the millijoule level. This system also amplif ied femtosecond pulses from a frequency-doubled Er-doped fiber laser.

The significance of adult hematuria: 1,000 hematuria evaluations including a risk-benefit and cost-effectiveness analysis.

Between March 1976 and June 1985, 1,000 consecutive adults with asymptomatic gross or microscopic hematuria in the absence of proteinuria were evaluated urologically. Lesions that could account for the hematuria were detected in 88.3 per cent of the patients. Life-threatening lesions were diagnosed in 9.1 per cent of the patients, while lesions requiring at least observation were present in 22.8 per cent. The incidence of life-threatening lesions increased with age, with a sharp increase after age 50 years. Life-threatening lesions were more common in men (13.6 per cent) than in women (4.9 per cent). In general, as the degree of hematuria increased so did the yield of life-threatening lesions; however, there was no "safe" lower limit of hematuria. Of the patients with life-threatening lesions 18.6 per cent had at least 1 urinalysis with less than 3 red blood cells per high power field within 6 months of the diagnosis. The direct medical cost of a hematuria evaluation was $777. The difference in direct medical costs to diagnose and treat localized versus metastatic genitourinary cancer was $48,070 in 3 matched pairs of patients. In this study group 77 of 84 patients (92 per cent) diagnosed with genitourinary cancer had localized disease. A hematuria evaluation was cost-effective for all groups studied. A literature-based estimate of the life-threatening risks of diagnostic studies applied to the study data resulted in a 1.1 per cent life-threatening risk per hematuria evaluation. For all categories studied, except for women less than 40 years old with microscopic hematuria, the risk of a hematuria evaluation was less than the incidence of life-threatening lesions discovered as a result of the evaluation. Asymptomatic hematuria, whether gross or microscopic, is a significant finding and warrants evaluation from a risk-benefit and cost-effectiveness standpoint.

Emphysematous prostatic abscess: diagnosis and treatment.

We report an unusual case of an emphysematous prostatic abscess. Prostatic abscess is a difficult clinical diagnosis associated with lower urinary tract symptomatology and frequently diabetes mellitus. Computerized axial tomography and transrectal or transurethral ultrasonography can assist in making a specific diagnosis. Definitive treatment is complete surgical drainage, which is achieved by transurethral resection of the prostate. Wide spectrum, adjuvant antibiotic therapy should be given to assure coverage of anaerobic bacteria.